GB2606489A

GB2606489A - Systems and devices for a floating renewable power station

Info

Publication number: GB2606489A
Application number: GB2210415.2A
Authority: GB
Inventors: Diddams James; Wood Tim
Original assignee: Achelous Energy Ltd
Current assignee: Achelous Energy Ltd
Priority date: 2021-05-06
Filing date: 2021-05-06
Publication date: 2022-11-09
Anticipated expiration: 2041-05-06
Also published as: GB2606490A; GB2606489B; GB2606488A; GB2606488B; GB2606390A; GB2606490B; GB2606390B; GB202210416D0; GB202210415D0; GB202210412D0

Abstract

A vertical axis turbine for a floating renewable power station has a plurality of blades 112, the displacement of which can be adjusted relative to the vertical axis, to vary the diameter of the turbine. A controller adjusts the diameter of the turbine based on an indication of power output and power demand. The diameter may be adjusted using horizontally adjustable struts having a fixed portion 402 and a moveable portion 404. The struts may be extended or contracted using a hydraulic or piezoelectric ram 508. This system allows the turbine diameter to be optimised for flow conditions and power demand.

Description

Systems and devices for a floating renewable power station

Field of Invention

The present application relates to systems, methods, and devices for a floating renewable 5 power station for generating power from flowing water, in particular a floating renewable power station, a vertical axis turbine for generating power from flowing water, and a vertical axis turbine blade.

Background

The harvesting of hydrokinetic energy from flowing water, known as hydropower, presents a highly attractive addition to the existing renewable energy sectors. Tidal energy is a type of hydropower which utilises tidal currents and streams to generate electricity. Hydropower can also be harnessed from anywhere there is a flow of water, for example the sea, locations where there are ocean currents which are not necessarily due to tidal flows, or other locations, such as rivers. Unlike renewable energy generation from wind, wave, or solar power, some types of hydropower may guarantee a predictable and consistent energy output and can contribute to the baseload power requirements of energy off-takers.

Despite this, tidal energy conversion technologies are still relatively undeveloped compared to other commercial renewable energy generation techniques.

Summary of Invention

Aspects of the disclosure are as set out in the independent claims and optional features are set out in the dependent claims. Aspects of the invention may be provided in conjunction with each other and features of one aspect may be applied to other aspects.

In a first aspect there is provided a floating renewable power station comprising a vessel and at least one vertical axis turbine for generating power from hydropower. In some 25 examples, the floating renewable power plant is configured for use with either ocean and/or -2 -river flow, for example including but not limited to tidal flows, ocean currents, and/or river flows.

Vertical axis turbines may be advantageous for use in hydropower compared to conventional horizontal axis turbines as vertical axis turbines may be omni-directional, meaning they do not have to be orientated in the direction of flow. This may be particulady advantageous for hydropower applications as water flow may change direction, for example in tidal currents. The use of vertical axis turbines may also remove the requirement for a yaw control system which adds complexity and cost to many horizontal axis turbine systems. Vertical axis turbines may also be easier and cheaper to produce as the generator can be vertically displaced from the turbine, for example above the water level. This may be advantageous compared to horizontal axis turbines for configured for hydropower energy generation which may require generators to be underwater. The position of the generator above water may also facilitate easier installation and maintenance of vertical axis turbines.

Furthermore, vertical axis turbines may be able to operate in regions of shallower water compared to horizontal axis turbines as horizontal axis turbines may have a larger vertical turbine span and thus require a greater operational depth than equivalent vertical axis turbines. Thus, vertical axis turbines may be suitable for use in shallower water locations, for example rivers, which would otherwise be unsuitable for horizontal axis turbines.

In some examples, the at least one vertical axis turbine may be a Darrieus turbine, squirrel cage Darrieus turbine, H-Darrieus turbine, Gorlov turbine, or Savonius turbine. In other examples, the at least one vertical axis turbine may be a different type of vertical axis turbine, for example the turbine of the fourth, fifth, and/or sixth aspect of the invention.

In some examples, the floating renewable power station may comprise at least two vertical 25 axis turbines.

In some examples, the vessel further comprises at least one outrigger structure. An outrigger structure may be advantageous as it may improve the stability and/or hydrodynamics of the vessel. In some examples, the vessel may be a "Banca" style boat. In some examples, the "Banca" style vessel may refer to a double-outrigger vessel, -3 -wherein an outrigger is arranged both starboard and portside to the vessel. A "Banca" style vessel may be advantageous as it may provide improved stability and hydrodynamics for the vessel. In some examples, the "Banca" style vessel may comprise a shallow hull, this may be advantageous to enable operation of the floating renewable power station in shallow waters, including rivers and shallow coastal waters. In some examples, the at least one turbine is coupled to the outrigger structure. In some examples, the diameter of the turbine (i.e. the turbine "span") is configured to be the less than or equal to the width of the outrigger, such that the turbine is configured to fit underneath outrigger structure, between the outermost point of the outrigger structure and the vessel.

The floating renewable power station further comprises a controller, wherein the controller is configured to export power to an onshore power network. In some examples, the onshore power network may be an electrical grid. In other examples, the onshore power network may be configured to provide power to off-grid communities. In these examples, the floating renewable power station may be located on an adjacent stretch of waterway to the local off-grid community.

In some examples, the renewable power station further comprises a pivot means configured to displace the vertical axis turbine. For example, the pivot means may be configured to raise and/or lower the vertical axis turbine into and/or out of the water. This may be advantageous as it allows for easier maintenance and/or repair of the turbines and easier transport of the floating renewable power station. In some examples, the pivot means is configured to raise and/or lower the vertical axis turbine relative to the outrigger structure.

In some examples, the at least one vertical axis turbine comprises a plurality of turbine blades. In some examples, the pivot is raised above the outrigger structure and configured such that when the at least one vertical axis turbine pivots, all the turbine blades are lifted out of the water. This may be advantageous as it allows for easier maintenance and/or repair of the turbines.

In some examples, the pivot means comprises a pin providing a pivot for the vertical axis turbine relative to the outrigger, and a hydraulic ram configured to pivot the vertical axis -4 -turbine about the pin to displace the vertical axis turbine. A hydraulic ram system may be advantageous as it is easily automated and may allow for remote operation. In other examples, the pivot means may comprise other means to displace the vertical axis turbine, for example a piezoelectric-actuated ram system, a motor and screw, or a pulley/winch mechanism.

In some examples, the controller is further configured to load shed in the event that power demand exceeds the export power level. Load shedding may be advantageous to prevent total power loss. In some examples, load shedding may involve tripping pre-determined consumers. This may be advantageous to prevent power loss for critical consumers.

In some examples, the controller is configured to shut down at least one of the vertical axis turbines in the event that power produced exceeds a selected threshold and/or power demand. This may be advantageous to limit the production profile in the event of overproduction.

In some examples, the floating renewable power station further comprises at least one solar panel for generating power from solar energy. In some examples, the floating renewable power station further comprises at least one fuel generator. In some examples. the fuel generator may be a diesel generator, or a bio-diesel generator. In some examples, the floating renewable power station further comprises other means for power generation, for example means for generating power from wind.

In some examples, the controller is further configured to vary the proportion of produced power used by components of the floating renewable power station including the controller. Powering the components of the floating renewable power station using power produced by the renewable power station may be advantageous as the floating renewable power station may be self-sustaining, thus reducing the running costs and external energy requirements. Varying the proportion of produced power used by the components may be advantageous due to the variable nature of renewable power production.

In some examples, the floating renewable power station further comprises means for hydrogen storage. In some examples, the floating renewable power station further comprises means for water sanitation, for example including water purification and/or -5 -waste sanitation.

In a second aspect there is provided a floating renewable power station comprising a turbine for generating power from hydropower and at least one solar panel for generating power from solar energy. The floating renewable power station further comprises a 5 controller configured to export power to an onshore power network and vary the proportion of energy from solar energy and from hydropower delivered to the onshore power network. This may facilitate load sharing. Load sharing may be advantageous due to the variable nature of renewable power production. For example, power generation may vary as dependent on weather conditions including light intensity, seasons, tidal currents, ocean 10 currents etc. Load sharing may allow the controller to react to variances in power generation from solar energy and from hydropower to ensure that power export demand is maintained.

In some examples, the floating renewable power station of the second aspect may include features of the floating renewable power station provided in the first aspect of the invention.

In some examples, the floating renewable power station further comprises at least one fuel generator. In some examples. the fuel generator may be a diesel generator, or a bio-diesel generator. In some examples, the floating renewable power station further comprises other means for power generation, for example means for generating power from wind. In some examples, the controller may be further configured to vary the proportion of energy from additional onboard means for power generation delivered to the onshore power network, for example including energy generated from a fuel generator and/or from wind power in load sharing. This may facilitate load sharing between energy from solar energy, hydropower, and other onboard means for power generation.

In some examples, a proportion of energy generated from at least one of solar energy, hydropower, and/or other on-board power generation means, is routed to power components of the floating renewable power station including the controller. This may be advantageous as the floating renewable power station may be self-sustaining, thus reducing the running costs and external energy requirements. In some examples, the controller is further configured to vary the proportion of energy from solar energy and/or -6 -from hydropower used by the components of the floating renewable power station including the controller. This may be advantageous as it may allow the floating renewable power station to dynamically respond to changes and fluctuations in, for example, power generation from solar energy and/or from hydropower, power demand of the onshore power network, and/or power usage the components of the floating renewable power station including the controller. For example, in some examples it may be preferred that energy produced from solar power is used to power the components of the floating renewable power station, and all energy generated from hydropower is exported. However, on cloudier days the energy generated from solar power may be insufficient to power all the components, thus the controller may be configured to divert a portion of the energy generated from hydropower to power at least a portion of the onboard components. In some examples, the controller may be further configured to vary the proportion of produced power used by components of the floating renewable power station according to export power demand.

In some examples, the floating renewable power station further comprises backup power means configured to deliver power in the event that the amount of available power from at least one of solar energy and hydropower falls below a selected threshold. This may be advantageous as it may provide an uninterruptible power supply to prevent power loss from critical components, for example the controller and/or safety critical components.

Some other examples of critical components may include instrumentation systems, emergency lighting, and a turbine brake control system. In some examples, the backup power means further comprises at least one of (i) a fuel generator and (ii) a battery. In some examples, the fuel generator may be a diesel generator, or a bio-diesel generator. In some examples, the battery is configured to be charged from at least one of solar energy, hydropower, and/or fuel generation. In some examples wherein the backup power means comprises both a fuel generator and a battery, the battery may be used to discharge power in the interim whilst the fuel generator is started up.

In some examples, the controller is further configured to monitor power demand of the onshore power network and power exported to the onshore power network by the floating 30 renewable power station, and wherein the controller is further configured to load shed in -7 -the event that the power demand exceeds the power exported. This may be advantageous to prevent total power loss. In some examples, load shedding may involve tripping predetermined consumers. This may be advantageous to prevent power loss for critical consumers.

In some examples, the floating renewable power station further comprises a turbine braking system, coupled to the controller. The turbine braking system may be configured to slow and/or stop the at least one turbine. In some examples, the controller is further configured to monitor one or more operational parameters of the floating renewable power station, wherein the controller is configured to slow and/or stop the at least one turbine using the turbine braking system in the event that the operational parameter exceeds a selected threshold.

In some examples, the operational parameters include at least power produced by the at least one turbine and wherein the turbine braking system is configured to slow and/or stop the at least one turbine in the event that the power produced by the at least on turbine exceeds a selected threshold. This may be advantageous as a safety precaution to ensure the turbine does not overproduce beyond its safety limits, for example, due to spinning at unsafe fast speeds.

In some examples, the operational parameters include at least power exported to the onshore power network by the floating renewable power station, and power demand of the onshore power network, wherein the turbine braking system is configured to slow and/or stop the at least one turbine in the event that the power exported exceeds the power demand. This may be advantageous to limit the production profile in the event of overproduction In a third aspect, there is provided a floating renewable power station comprising at least one turbine for generating power from hydropower, a plurality of sensors configured to obtain an indication of one or more operational parameters of the renewable power station of the renewable power station, and a controller wherein the controller is configured to receive the indication of one or more operational parameters from the plurality of sensors. -8 -

The floating renewable power station further comprises a turbine braking system, coupled to the controller, configured to slow and/or stop the at least one turbine in the event that the indication of the operating parameter exceeds a selected threshold. This may be advantageous by making the power station autonomous without the need for daily 5 intervention. This may be particularly advantageous as the floating renewable power station may be located in remote, offshore locations. Example functionality may include automatically limiting the production profile of the renewable power station, for example, in the event of overproduction. The automated system including the turbine braking system may also be advantageous as a safety precaution to ensure the turbine does not 10 overproduce beyond its safety limits, for example, due to spinning at unsafe fast speeds.

In some examples, the turbine braking system has at least one of the following functions: (i) controlled braking, (ii) park brake function, and/or (iii) emergency stop. In some examples, the turbine braking system is served by a single hydraulic power unit, coupled to the controller.

In some examples, controlled braking, for example due to overspeed, ensures the shaft speed is maintained to within its design limits. Controlled braking may also be engaged to limit the production profile of the turbines in the event of overgeneration of energy. In some examples, a turbine shaft torque sensor (RPM) is coupled to the controller, and a signal from the controller can engage the turbine brakes in the event the shaft speed exceeds a selected threshold.

In some examples, the park brake function brake shall be applied for when the turbine is installed, to be inspected, or for maintenance regimes. The park brake function is configured to prevent rotation of the turbine.

In some examples, the emergency stop brake function shall be activated when there is 25 power blackout and automatic control of the turbine speed is lost. -9 -

In some examples, the controller may control the turbine braking system for each turbine individually. In some examples, the controller may control the turbine braking system for a plurality of turbines concurrently.

In some examples, the floating renewable power station further comprises an uninterruptible power supply. The uninterruptible power supply may be configured to power safety critical components including at least the turbine braking system. This may be advantageous as a safety precaution to ensure that the turbine braking system is powered in the event of an emergency. Some other examples of critical components may include instrumentation systems and emergency lighting. In some examples, the uninterruptible power supply further comprises at least one of (i) a fuel generator and (ii) a battery. In some examples. the fuel generator may be a diesel generator, or a bio-diesel generator. In some examples, the battery is configured to be charged from at least one of solar energy, hydropower, and/or fuel generation. In some examples wherein the backup power means comprises both a fuel generator and a battery, the battery may be used to discharge power in the interim whilst the fuel generator is started up.

In some examples, the controller is configured to release the turbine braking system in the event that a second indication of the operating parameter is below a second selected threshold. This may be advantageous as it may enable energy generation from hydropower to automatically resume in the event that the operational parameter which initially caused the braking system to engage restabilises. This may be advantageous as power generation is not disabled for an unnecessarily long time period which would reduce the efficiency of the floating renewable power station.

In some examples, the floating renewable power station further comprises a communication module, coupled to the controller, wherein the communication module is configured to send the indication of one or more operational parameters to a remote device. This may be advantageous as it allows remote monitoring of the floating renewable power station, thus reducing labour-intensive routine inspection and maintenance checks. This may be particularly advantageous as the floating renewable power station may be located in remote, offshore locations. In some examples, the communication module may -10 -communicate using an Internet of Things (I0T) gateway. In some examples, the communication module may communicate with a cloud network platform. In some examples, the communication module is configured to share the indication of operational parameters. In some examples, the communication module is configured to share at least one of floating renewable power station performance data, fault detection, diagnostics, and/or control. In some examples, the floating renewable power station performance data may include at least one of productivity chart, river flow resource chart, availability chart, and/or production income report.

In some examples, the turbine braking system is configured to slow and/or stop the at least one turbine in response to receiving a signal from the remote device. This may be advantageous as it allows remote control of the turbines of the floating renewable power station. The ability to remotely to slow and/or stop the at least one turbine may act as a safety precaution, for example, in the event of a technical fault or potential problem, it allows the turbines to be remotely disabled before an engineer is able to reach the power station. This may be particularly advantageous as the floating renewable power station may be located in remote, offshore locations.

In some examples, the communication module is further configured to receive signals from the remote device, and wherein the controller is configured to start-up and/or shut down a turbine in response to a signal received by the communication module from the remote device. This may be advantageous as control of the turbines by the remote device may override the automatic monitoring and control system, for example in case of technical fault within the monitoring system. This may also be advantageous as the turbines may be shut down preventatively before issues are detected by the sensing system, for example in the event of a natural disaster forecast.

In some examples, the floating renewable power station further comprises a system redundancy agent, coupled to the controller, configured to transmit data to a separate microgrid cloud platform. In some examples, the system redundancy agent further comprises a computing device as a backup, for example a Raspberry Pi computer. The redundancy agent may allow monitoring and control services similar to the features transmitted to the remote device via the communication module. The system for signalling between the floating renewable power station and the cloud platform may support scalability, high availability, and low latency. In some examples, standard MQTT network protocol is used for its signalling system which is suited for frontier locations where Wide Area Network (WAN) connections are transiently unavailable.

In some examples, the turbine for generating power from hydropower is a vertical axis turbine. In some examples, the floating renewable power station further comprises at least one solar panel for generating power from solar energy. In some examples, the floating renewable power station of the third aspect may include features of the floating renewable power station provided in the first aspect and/or second aspect of the invention.

In some examples, the one or more operational parameters detected by the plurality of sensors comprise at least one of temperature, humidity, inclination, position, water flow speed, turbine vibration, turbine speed.

Some example systems involving the monitoring of operational parameters and control of 15 the turbines using the turbine braking system are included below.

Temperature and/or humidity monitoring In some examples, temperature and/or humidity sensors may be installed on the floating renewable power station, for example proximal to the controller, for room temperature and humidity measurement. In some examples, the sensor may be capable of measuring temperature ranging from -15°C to +60°C and relative humidity from 0 -100 % RH. In some examples, a high temperature alarm may be generated and transmitted to a remote device to notify the operations and maintenance team in the event that the temperature exceeds a selected threshold, for example 45°C. Upon receiving the warning alarm signal the operations and maintenance team can send a remote signal via the remote device to engage the turbine brakes and shut down the turbine system, allowing the operations team to diagnose the problem and intervene. In some examples, the controller automatically engages the turbine brakes and/or -12 -shuts down the turbine system in response to the temperature and/or humidity exceeding a selected threshold, for example 50°C.

(ii) Location/position monitoring In some examples, the location/position of the floating renewable power station shall be monitored, for example using a differential global positioning system (DGPS). In some examples, the floating power station may be set up with a geofence alert. If the floating power station moves more than a selected threshold outside its geofence, for example 20% of the water depth outside the geofence, an alert may be sent to the remote device so the operations team can intervene accordingly. In some examples, the controller automatically engages the turbine brakes and/or shuts down the turbine system in response to the location exceeding a selected threshold beyond the geofence.

(iii) Inclination monitoring In some examples, the floating renewable power station further comprises sensing means for inclination measurement, for example an inclination transmitter. In some examples, the measurement range may be from -90° to + 90°. In some examples, an alarm is generated when the inclination of the floating renewable power station exceeds a selected threshold, for example 30° either port or starboard side. Notification may be sent to the remote device to alert the operations team. In some examples, the controller automatically engages the turbine brake system to slow down and/or stop the at least one.

(iv) Water speed monitoring In some examples, the floating renewable power station is further configured to measure water flow speed, for example using a retractable turbine type flow meter installed overboard. In some examples, the real time water flow data is monitored by the controller. In some examples, the controller is configured to send a signal to the turbine braking system which engages the turbine brakes to slow and/or stop the turbine in the event that water flow speed exceeds a selected threshold. In some -13 -examples, the controller is configured to send a signal to the communication module which sends an alert to the remote device in the event that the water flow speed exceeds a selected threshold. In some examples, a warning alert may be sent to the remote device when the water flow speed exceeds, for example, 3.2 m/s; and the automatic engagement of brakes to slow and/or stop the turbine may be employed when the water flow speed exceeds, for example, 3.5 m/s. In some examples, upon flows below a selected threshold, for example 3.2 m/s, the controller will send a separate signal to release the turbine brakes so tidal production can restart.

(v) Fire monitoring In some examples, the floating renewable power station further comprises a fire alarm system. In some examples, the fire alarm may comprise at least one of smoke detectors, heat detectors, and a manual call point. Smoke or heat detection from any device shall trigger the fire alarm and transmit an alarm status to the controller which further relays a signal to the communications module to send an alert to the remote device to notify the operations team. In some examples, the controller automatically engages the turbine brakes and/or shuts down the turbine system in response to the triggering of the fire alarm.

(vi) CCTV monitoring In some examples, the floating renewable power station further comprises a CCTV system, comprising a recorder and at least one camera configured for continuous surveillance of the floating renewable power station. In some examples, the CCTV system further comprises at least one camera configured for night-time surveillance, for example an infrared camera. In some examples the at least one camera shall trigger auto record if any intrusion or motion is detected on and/or around the floating renewable power station. In some examples, the controller is configured to send a signal to the communication module to send an alert to the remote device to notify the operations team in the event that an intrusion or motion is detected on and/or around the floating renewable power station. In some examples, upon receiving the signal, the operations team can access the CCTV surveillance system via the remote device and -14 -review the real-time footage allowing the team to intervene if required.

(vii) Turbine transmission monitoring In some examples, the at least one turbine comprises a transmission, wherein the transmission comprises a turbine gearbox and turbine generator. The transmission is fitted with several sensors to allow at least one of control, fault diagnostics, production profile and alarm status to be communicated to the controller, and in some examples the remote device.

(viii) Turbine overspeed In some examples, turbine overspeed may be measured in terms of at least one of turbine gearbox slow shaft and/or fast shaft speed, and/or turbine generator speed.

In some examples, the sensor provides rotation counts controller in which the controller uses the data to calculate the revolutions per minute (RPM) of the turbine.

In some examples, turbine gearbox slow shaft overspeed threshold may be > 2.5 rad/s, and/or turbine fast shaft overspeed threshold may be > 62.4 rad/s. In some examples, turbine generator overspeed threshold may be > 62.4 rad/s.

Upon receiving the overspeed signal at the controller, the controller will send a signal to the turbine brake system to engage the brakes, and in some examples stop the turbines. In some examples, an alert notification will also be sent to the remote device via the communications module.

In some examples, upon the turbines being shut down, export power will be transmitted via the solar power and/or fuel generator based on onshore demand.

(ix) Turbine gearbox oil temperature In some examples, the gearbox is fitted with a temperature sensor which monitors oil temperature in real-time. In the event that oil temperature exceeds a selected threshold, for example > 80°C, the controller may send a signal to the turbine brake -15 -system to apply the brakes and/or stop the turbines. In some examples, notification will be sent to the operations team accordingly via the remote device.

(x) Turbine gearbox oil level In some examples, the turbine gearbox is equipped with a high/low level liquid sensor configured to detect the oil level. In some examples, real-time oil levels will be measured throughout operation. In the event that the sensor detects the oil level to be below a first selected threshold and/or above a second selected threshold, the controller will send a signal to the turbine brake system to apply the brakes and stop the turbines. In some examples, notification will be sent to the operations team via the remote device.

(xi) Turbine vibration monitoring In some examples, each turbine is fitted with a vibration module sensor to monitor the mechanical components within the turbine system. The monitoring system may give an overview of the entire system and may capture any of unbalance, bearing related damage, transmission faults, and/or improper alignment of the machine trains.

In the event that the vibration module senses a fault detection, i.e. vibration above a selected threshold, the controller will send a signal to the turbine brake control system to apply the brakes and/or stop the turbines. In some examples, real time data and/or diagnostics are recorded and can be viewed by the remote device, for example through the IOT gateway. In some examples, during commissioning, the status under normal operating conditions shall be determined and from the characteristic values measured, the operations team may define the selected threshold to engage breaking.

(xii) Turbine bearing housing temperature monitoring In some examples, each turbine comprises a bearing housing structure which encapsulates turbine shaft bearings. The turbine bearing housing structure further comprises a sensor to monitor an increase in temperature in the bearing housing structure, for example a thermocouple. In some examples, in the event that the -16 -temperature exceeds a first selected temperature threshold, the controller will send a signal to the communication module to send a signal to the remote device to notify the operations team for diagnostics and/or intervention. In some examples, in the event that the temperature exceeds a second selected temperature threshold, for example > 70 °C, the controller will send a signal to the turbine brake control system to apply the brakes and/or stop the turbines (xiii) Bilge level sensor monitoring In some examples, the vessel of the floating renewable power station further comprises a hull, a plurality of level gauge sensors configured to monitor ingress of water level inside the hull, and a bilge pump system. In the event that a height of water is detected inside the hull above a selected threshold, for example 100 mm, the bilge pump system will be activated to pump out the water. In some examples, the controller will also send a signal to the communication module to send an alert to the remote device to notify the operations team.

(xiv) Solar Inverter monitoring In some examples, the floating renewable power station further comprises at least one solar inverter, for example a string inverter, to convert the direct current (DC) electricity captured by the solar panels into alternating current (AC). In some examples, the at least one solar inverter comprises sensing means configured for smart power metering functionality and/or fault code detection and information which may be transmitted to the controller. Each solar inverter may be monitored allowing for ease of identification of faults. Power generation / smart metering is captured in real-time and may be processed by the controller.

(xv) Tidal Converter monitoring and control In some examples, each turbine has a dedicated converter and the controller is coupled to each of the converters. The controller can monitor a number of parameters withing the converters, including but not limited to generated power, torque, temperature, frequency, and error codes. Upon detection of certain error codes, the controller can -17 -automatically shut down a turbine by engaging the turbine brakes. (xvi) Fuel generator monitoring and control In some examples wherein the floating renewable power station further comprises a fuel generator, the fuel generator may be coupled to the controller wherein the controller is configured to control the start-up or shut down of the generator. In some examples, the fuel generator further comprises a plurality of sensors, coupled to the controller, configured to monitor at least one of fuel levels, temperature, and/or other operational performance, and control the start-up or shut down of the generator accordingly.

In a fourth aspect, there is provided a vertical axis turbine for generating power from hydropower, comprising a vertical axis turbine shaft and a plurality of vertical axis turbine blades, wherein the displacement of the vertical axis turbine blades relative to the vertical axis turbine shaft is configured to be adjustable, such that the diameter of the turbine span is adjustable. This may be advantageous as adjusting the diameter of the turbine span alters the 'swept area' of the turbine. 'Swept area' of a turbine is directly proportional to power generation. Therefore, increasing the diameter of the turbine span increases the amount of power generation produced per rotation of the turbine. An adjustable turbine may also be advantageous as the turbine span diameter can be adjusted according to the profile of the water flow and/or the power demand. For example, the diameter of the turbine span may be reduced to limit the production profile in the event of overproduction, or the diameter of the turbine span may be increased in the event of underproduction.

In some examples, the vertical axis turbine for generating power from hydropower further comprises a plurality of horizontal adjustable struts. The plurality of horizontal adjustable struts may be coupled between the vertical axis turbine shaft and the plurality of vertical axis turbine blades such that the diameter of the turbine span is configured to be adjusted by extending and/or contracting the horizontal adjustable struts.

In some examples, the plurality of horizontal adjustable struts comprises a fixed portion having a longitudinal axis, and a moveable portion. In some examples, the diameter of the turbine span is configured to be adjusted by moving the movable portion of each horizontal -18 -adjustable strut in a direction parallel to the longitudinal axis of the fixed portion. In some examples, the fixed portion and the movable portion of each horizontal adjustable strut are configured to extend and/or contract in a telescopic arrangement. For example, the fixed portion of each horizontal adjustable strut is configured to receive the movable portion of the strut in a direction parallel to the longitudinal axis of the fixed portion.

In some examples, the vertical axis turbine further comprises a hydraulic ram system configured to extend and/or contract the horizontal adjustable struts. This may be advantageous as it may facilitate automation of extension and/or contraction of the horizontal adjustable struts In some examples, the vertical axis turbine further comprises a controller, wherein the controller is configured to obtain an indication of one or more operating parameters of the vertical axis turbine and to adjust the diameter of the turbine span in the event that the indication of the operating parameter exceeds or is less than a selected threshold. This may be advantageous in making the power station autonomous without the need for daily intervention. This may be particularly advantageous as the floating renewable power station may be located in remote, offshore locations. In some examples, the operational parameters include at least one of water flow speed and/or power output. Example functionality may include automatically reducing the diameter of the turbine span to limit the production profile of the renewable power station, for example, in the event of overproduction; and/or increasing the diameter of the turbine span to increase the production profile of the renewable power station. Similarly, in the event that the water flow rate reduces, for example due to reduced tidal currents, the diameter of the turbine span may be increased to increase the production profile of the renewable power station. This may allow the turbine to automatically adapt to the variable profile of the environment, including variable water flow profiles.

In some examples, the adjustable vertical axis turbine of the fourth aspect may be configured for use as part of the floating renewable power stations of the first, second, and third aspects of the invention.

-19 -In a fifth aspect, there is provided a vertical turbine blade for generating power from hydropower comprising a proximal end, a distal end, and a cross section, parameterised by a length and a width. The vertical turbine blade further comprises a portion between the proximal end and the distal end, with an enlarged cross section relative to the cross section at the proximal end and the cross section at the distal end. This design may be advantageous as it may have improved hydrodynamics compared to a conventional, fixed cross-section hydropower turbine blade. In some examples, the cross section at the proximal end and distal end is teardrop shaped. In some examples, the cross section at the enlarged portion is teardrop shaped.

In some examples, the portion with an enlarged cross section is equidistant from the proximal end and the distal end.

In some examples, the enlarged cross section is enlarged in length relative to the cross section at the proximal end and distal end. In some examples, the enlarged cross section has a constant width relative to the cross section at the proximal end and distal end. In other examples, the enlarged cross section is enlarged in width relative to the cross section at the proximal end and distal end.

In some examples, the vertical turbine blade further comprising at least one tapered portion, arranged between the portion with an enlarged cross section and the proximal end and/or distal end.

In some examples, the vertical axis turbine blade may be configured for use within the vertical axis turbine of the fourth aspect. In some examples, the vertical axis turbine blade may be configured for use as part of the floating renewable power stations of the first, second, and third aspects of the invention.

In a sixth aspect, there is provided a vertical axis turbine for generating power from 25 hydropower, comprising a vertical axis turbine shaft, a plurality of horizontal adjustable struts coupled to the vertical axis turbine shaft, and a plurality of vertical axis turbine blades configured to be reversibly coupled to the plurality of horizontal adjustable struts. The -20 -plurality of horizontal adjustable struts of the vertical axis turbine are configured to attach to a plurality of different types of vertical axis turbine blades. In some examples, the different types of vertical axis turbine blades comprise different sizes and/or shapes of vertical axis turbine blades. This may be advantageous as it facilitates easy assembly turbine and/or changing of the turbine blades. This may be advantageous as a single vertical axis turbine is configured to fit a plurality of different types of turbine blades, such that turbine blades can be easily swapped out depending on location and/or the profile of water flow without replacing the turbine as a whole. For example, a turbine may be used in a location of strong ocean currents, similarly the same turbine may be used in a location of tidal currents in a river, however the turbine blades may be easily changed between locations to ensure the turbine blades are most suitable for the application. This may also be advantageous to extend the lifecycle of a turbine as the turbine blades can be easily replaced during wear, without replacing the whole turbine.

In some examples, each horizontal adjustable strut of the vertical axis turbine comprises a blade connector plate at one end, configured to reversibly attach to a plurality of different types of vertical axis turbine blades.

In some examples, the plurality of vertical axis turbine blades of the vertical axis turbine further comprise at least one track, and wherein the plurality of horizontal adjustable struts further comprise a slot configured to receive the track of the vertical axis turbine blade. This may be advantageous as a plurality of different types of blades can be reversibly attached to the plurality of horizontal adjustable struts by a standard size track, regardless of the shape and size of the blade. In some examples, the slot to receive the track of the vertical axis turbine is disposed on the blade connector plate of horizontal adjustable strut.

In some examples, the vertical axis turbine may include features of the vertical axis turbine of the fourth aspect. In some examples, the vertical axis turbine may be configured for use within the vertical axis turbine blade of the fifth aspect. In some examples, the vertical axis turbine may be configured for use as part of the floating renewable power stations of the first, second, and third aspects of the invention. -21 -

In a seventh aspect, there is provided a floating renewable power station comprising at least one hydropower turbine and at least a pair of venturi ducting plates. The venturi ducting plates are configured to increase the water flow velocity through the at least one hydropower turbine. This may be advantageous as water flow velocity through the hydropower turbine is proportional to the power generated by the hydropower turbine, therefore increasing the water flow velocity may increase the power generated. Thus, the venturi ducting plates may increase the power generation of the floating renewable power station and increase the efficiency of the floating renewable power station.

In some examples, the at least one hydropower turbine is a vertical axis hydropower 10 turbine. In some examples, the venturi ducting plates are curved.

In some examples, the floating renewable power station of the seventh aspect may include features of the floating renewable power stations of the first, second, and/or third aspects of the invention. In some examples, the floating renewable power station of the seventh aspect may be configured for use with the turbines of the fourth and sixth aspect of the invention, and/or the turbine blade of the fifth aspect of the invention.

Brief Description of Drawings

Embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: Figures 1A and B show an example floating renewable power station from different 20 perspectives.

Figures 2A to 20 show an example vertical axis turbine and pivot system, for use in a floating renewable power station such as the example floating renewable power station of Figures 1A and 1B.

Figure 3 shows an example floating renewable power station, such as the example floating 25 renewable power station of Figures 1 to 2, comprising two adjustable vertical axis turbines.

Figure 4 shows an example adjustable turbine, for use in a floating renewable power station such as the example floating renewable power station of Figures 1 to 3.

-22 -Figures 5A and 5B show example horizontal adjustable strut configurations for an adjustable turbine, for use in a floating renewable power station such as the example floating renewable power station of Figures 1 to 4.

Figures 6A and 6B show an example turbine blade and blade connector plate of a vertical 5 axis turbine, for use in a floating renewable power station such as the example floating renewable power station of Figures 1 to 5.

Figure 7 shows an example vertical axis turbine blade, for use in a floating renewable power station such as the example floating renewable power station of Figures 1 to 6.

Figure 8 shows an example floating renewable power station, such as the example floating 10 renewable power station 100 of Figures 1 to 7, further comprising a pair of venturi ducting plates associated with each turbine.

Detailed Description

In the context of the present disclosure other examples and variations of the apparatus and methods described herein will be apparent to a person of skill in the art.

The floating renewable power station 100 shown in Figure 1 comprises a vessel 102 comprising two outrigger structures 104 arranged starboard and portside of the vessel 102. The outrigger structures 104 extend in a perpendicular direction away from the side of the vessel 102 and comprise a platform 105. In this example, each outrigger structure 104 further comprises a floating pontoon 106 at the opposite end of the outrigger structure 104 to the vessel 102. The floating pontoon 106 is arranged parallel to the vessel 102. In the example shown, the vessel 102 has a length of approximately 24000 mm, and the floating pontoons 106 have a length of approximately 12590 mm. The pontoons 106 are displaced approximately 11045 mm from the centre line of the vessel 102. In other examples, other sizes and geometries may be used.

The vessel 102 provides a main hull, whereas the floating pontoons 106 form subsidiary hulls. In other examples, the floating renewable power station 100 comprises at least four hulls. In this example, the outrigger structure 104 is made of reinforced concrete beams, -23 -however in other examples, other materials may be used such as other concretes, metals, plastics, or wood. In this example the floating pontoon 106 may comprise polystyrene foam partially encased in a concrete shell, however in other examples, other floating materials may be used such as other concretes, metals, plastics, or wood. In this example the hull of the vessel 102 may comprise polystyrene foam partially encased in a concrete shell, however in other examples, other floating materials may be used such as other concretes, metals, plastics, or wood.

The floating renewable power station 100 further comprises two vertical axis turbines 108. In other examples, horizontal axis turbines may be used. Each vertical axis turbine 108 comprises a vertical axis turbine shaft 110, a plurality of vertical axis turbine blades 112, and a plurality of horizontal struts 114, wherein the plurality of horizontal struts 114 are coupled perpendicular between the vertical axis turbine shaft 110 and the plurality of vertical axis turbine blades 112. The plurality of horizontal struts 114 are arranged into pairs, wherein the horizontal struts 114 within a pair are vertically displaced from each other. Each horizontal strut 114 comprises a proximal end and a distal end. The distal end of each horizontal strut 114 is coupled to the vertical axis turbine blade 112, such that each pair of horizontal struts is coupled to the top and bottom of each vertical axis turbine blade 112. Each vertical axis turbine blade 112 is arranged such that the wide face of the vertical axis turbine blade 112 is perpendicular to the horizontal struts 114. The proximal end of each horizontal strut 114 is coupled to the vertical axis turbine shaft 110. In this example, each vertical axis turbine 108 comprises four vertical axis turbine blades 112. The pairs of horizontal struts 114 are arranged in a cross-shape configuration, radiating outwards from the vertical axis turbine shaft 110. An example vertical axis turbine 108 is described in more detail in Figure 4. In some example, other vertical axis turbines may be used, including Darrieus turbines, squirrel cage Darrieus turbines, H-Darrieus turbines, Gorlov turbines, or Savonius turbines.

The vertical axis turbines 108 are positioned starboard and portside of the vessel 102, each located on the outrigger structures 104. In this example, the vertical axis turbines 108 are positioned at the edge of each outrigger structure 104, nearest the stern 101 of the 30 vessel 102.

-24 -Each vertical axis turbine 108 further comprises a vertical axis housing structure 116, vertically displaced above the vertical axis turbine shaft 110. The vertical axis housing structure 116 houses the turbine power generator. The vertical axis housing structure 116 is arranged above the outrigger structure 104. This may be advantageous as the turbine power generator may be arranged above the water level. In this example, the vertical axis housing structure 116 is also coupled to a pivot means, an example pivot means is shown in more detail in Figures 2A to 20. The pivot is raised above the outrigger structure 104, coupled to the vertical axis housing structure 116.

The floating renewable power station 100 further comprises a plurality of solar panels 118. 10 In this example, the plurality of solar panels 118 are arranged across the platform 105 of the outrigger structures 104 and along the vessel 102.

The floating renewable power station 100 further comprises a power control house 122. The power control house 122 is arranged on the vessel 102. The power control house 122 houses a control and monitoring system, including a controller. In this example, a plurality 15 of solar panels 118 are additionally arranged on the roof of the power control house 122.

Each turbine 108 further comprises a turbine braking system. In this example, the turbine braking system includes two turbine brakes, for example brake callipers, connected to a hydraulic actuator system. In this example, the hydraulic actuator system, comprising a hydraulic pump, is located inside the control house 122 and connects to the brake callipers via hydraulic tubing routed to the port and starboard turbine brakes. The hydraulic tubing connected to the turbine brakes further comprises a valve. In this example, the valve is a "seat valve", for example a 3/2-way solenoid valve.

The floating renewable power station 100 further comprises a backup fuel generator 120. In this example the fuel generator 120 is a diesel generator, however in other examples a bio-diesel generator, or other fuel generator may be used. The floating renewable power station 100 further comprises a backup battery 128. In this example, the fuel generator and battery are arranged at the stern 101 of the vessel 102, proximal to the power control house 122.

The floating renewable power station 100 further comprises a transformer 130, arranged -25 -on the vessel 102 proximal to the bow 103. The transformer 130 is coupled to the power generation means, including the turbine and solar panels.

The floating renewable power station 100 further comprises debris deflectors 124. In this example, the debris deflectors 124 are diagonally arranged between the bow 103 of the 5 vessel 102 and the ends of the starboard and portside pontoons 106 proximal to the bow 103. In other examples, the debris deflectors 124 are arranged along the edge of the outrigger structures 104, opposite the vertical axis turbines 108. The debris deflectors in this example comprise a plurality of vertical stanchions. In some examples, the stanchions are made of metal or rope; in some examples a net or mesh is supported between the 10 stanchions.

The floating renewable power station 100 further comprises mooring lines 126, arranged at the bow 103 and stern 101 of the vessel 102.

The floating renewable power station 100 further comprises safety features including safety railings 132 and lighting 134. The safety railings 132 are arranged around the 15 perimeter of the platform 105 and the vessel 102. The lighting 134 comprises a plurality of navigational lights and flood light, including emergency flood lights.

The vertical axis turbines 108 are configured for power generation from hydropower, for example using tidal power. In this example, the diameter of each vertical axis turbine 108 span is configured to fit underneath the outrigger structure 104, between the vessel 102 and the pontoon 106. In this example, the turbine blades 112 may be configured for improved hydrodynamic performance relative to conventional straight turbine blades. An example turbine blade 112 is shown in more detail in Figure 7. The vertical axis housing structure 116 of the vertical axis turbine 108 is configured to remain above the outrigger structure 104, out of the water.

The turbine braking system is configured to slow and/or stop the at least one turbine 108, and/or keep the at least one turbine 108 in a parked position. In this example, the turbine brakes are configured to generate a brake force on a brake disc connected to the turbine 108 to decelerate turbine rotation, stop turbine rotation, or keep the turbine 108 in a parked position. In this example, the controller is further configured to monitor one or more -26 -operational parameters of the floating renewable power station and wherein the controller is configured to slow, stop, and/or park the at least one turbine using the turbine braking system in the event that the operational parameter exceeds a selected threshold.

In this example, the pivot means is configured such that when each vertical axis turbine 5 108 pivots all of the plurality of blades 112 are lifted out of the water. This may be advantageous as it allows for easier maintenance and/or repair of the turbines.

The solar panels 118 are configured for power generation using solar energy.

The debris deflectors 124 are configured to catch and stop debris which may otherwise get caught in and/or damage the turbines 108.

The mooring lines 126 are configured to secure the floating renewable power station 100 in position.

The controller is configured to export power to an onshore power network and vary the proportion of energy from solar energy and from hydropower delivered to the onshore power network. This may facilitate load sharing. The controller may be further configured to additionally vary the proportion of energy from other onboard means for power generation exported to the onshore power network, for example including energy generated from the fuel generator 120.

The transformer 130 is configured to step-up the voltage of electricity generated onboard the floating renewable power station 100 prior to being exported to the onshore power 20 network. This may be advantageous to reduce energy losses during export.

The controller may be further configured to load shed in the event that power demand exceeds the export power level. Load shedding may be advantageous to prevent total power loss. In some examples, load shedding may involve tripping pre-determined consumers. This may be advantageous to prevent power loss for critical consumers.

The controller may be configured to slow down and/or stop at least one of the vertical axis turbines 108 in the event that power produced exceeds a selected threshold and/or power demand. Slowing down and/or stopping a turbine 108 may be achieved by engaging the -27 -turbine braking system. This may be advantageous to limit the production profile in the event of overproduction.

The controller may be further configured to vary the proportion of produced power used by components of the floating renewable power station 100 including the controller. This may 5 be advantageous due to the variable nature of renewable power production and power demand.

Automated control of the floating renewable power station 100 by the controller may be advantageous as it may allow the floating renewable power station 100 to dynamically respond to changes and fluctuations in, for example, power generation from solar energy and/or from hydropower, power demand of the onshore power network, and/or power usage the components of the floating renewable power station 100.

The backup fuel generator 120 and battery 128 are configured to deliver power in the event that the amount of available power from at least one of solar energy and hydropower falls below a selected threshold. This may be advantageous as it may provide an uninterruptible power supply to prevent power loss from critical components on the floating renewable power station 100, for example the controller and safety critical components, including the turbine braking system and emergency lights. In this example, the battery 128 is configured to be charged from at least one of solar energy, hydropower, and fuel generation.

During hydropower generation, the plurality of turbine blades 112 are at least partially submerged underwater. The turbine 108 is driven to rotate by the flow of water, for example from tidal currents. As the turbine 108, including the turbine shaft 110, rotates, electrical energy is generated by the turbine generator, housed within the vertical axis housing structure 116.

During installation, maintenance, or other periods of non-use, the turbine 108 is displaced 25 about the pivot such that the plurality of turbine blades 112 are removed from the water. When the turbine blades are removed from the water, the turbine braking system may be automatically engaged, for example to park the turbines.

-28 -In this example, braking is initiated by de-energising the seat valve which opens the valve. The turbine brake hydraulic actuator system then runs the hydraulic pump to pump fluid through the hydraulic tubing and apply the turbine brakes, in this example brake callipers. The pump runs until a pressure switch reaches a set working pressure which signals that 5 the seat valve should be energised (closed) and the hydraulic pump switched off (brakes maintain applied). In case of failure of pressure switch, the turbine braking system further comprises a mechanical pressure relief valve to dump the pressure to tank in excess of threshold pressure, in this example 210bar. To release the brakes, the seat valve is de-energised whilst the hydraulic pump is switched off to reduce the fluid pressure, thus 10 releasing the brake callipers.

In use, the mooring lines 126 attach to the sea floor / riverbed to secure the floating renewable power station 100.

In use, load sharing may be advantageous due to the variable nature of renewable power production. For example, power generation may vary as dependent on weather conditions including light intensity, seasons, tidal currents, ocean currents etc. Load sharing may allow the controller to react to variances in power generation from solar energy and from hydropower to ensure that power export demand is maintained.

In use, a proportion of energy generated from at least one of (i) solar energy and (ii) hydropower is routed to power components of the floating renewable power station 100 including the controller. In this example, energy generated from solar energy is primarily used to power the components of the floating renewable power station 100, however if the energy generated from solar energy is insufficient, a proportion of energy generated from hydropower may also be routed to supplement the power supplied to the floating renewable power station 100. This may be advantageous as the floating renewable power station may be self-sustaining, thus reducing the running costs and external energy requirements.

In use, in the event that the amount of available power from at least one of solar energy and hydropower falls below a selected threshold the battery 128 may be used to discharge power to the critical components on the floating renewable power station 100 whilst the -29 -fuel generator 120 is started up. The fuel generator 120 may then be used to power the critical components on the floating renewable power station 100 until the amount of available power from at least one of solar energy and hydropower falls is operational above a selected threshold.

In use, the controller monitors operational parameters including at least power exported to the onshore power network by the floating renewable power station 100, and power demand of the onshore power network. In the event that the power exported exceeds the power demand, the controller sends a signal to the turbine braking system which slow and/or stops at least one turbine 108. This may be advantageous to limit the production profile in the event of overproduction. The operational parameters may also include at least power produced by the at least one turbine, and wherein in the event that the power produced by the at least on turbine exceeds a selected threshold, the controller sends a signal to the turbine braking system which slows and/or stops at least one turbine 108. This may be advantageous as a safety precaution to ensure the turbine does not overproduce beyond its safety limits, for example, due to spinning at unsafe fast speeds.

Figures 2A to 20 show an example pivotable vertical axis turbine 108, for use in a floating renewable power station such as the example floating renewable power station 100 of Figures 1A and 1B. The vertical axis turbine 108 comprises a vertical axis housing structure 116, vertically displaced above the vertical axis turbine shaft 110 and arranged above the platform 105 of the outrigger structure 104. The vertical axis housing structure 116 houses the turbine power generator 206 which is coupled to the turbine shaft 110. In this example, the vertical axis housing structure 116 is also coupled to a pivot means.

The pivot means comprises a pin 200 providing a pivot for the vertical axis turbine 108. The pivot pin 200 is vertically displaced above the plane of the outrigger 104 and platform 105 and is coupled to the vertical axis housing structure 116 of the vertical axis turbine 108 to the platform 105 of the outrigger 104. In this example, the pivot pin 200 is located approximately 800 mm above the platform 105 of the outrigger 104.

In this example, the pivot means further comprises a hydraulic ram 202. In other examples, the hydraulic ram 202 may be replaced by other means to pivot the turbine 108, for -30 -example using a motor and screw, or a pulley/winch mechanism. The hydraulic ram 202 is coupled to the vertical axis housing structure 116 of the vertical axis turbine 108, above the pivot pin 200, via a pin and bracket 204. The other end of the hydraulic ram 202 is coupled to the platform 105 of the outrigger 104 via a second pin and bracket 205. In this 5 example, the hydraulic ram 202 pin and bracket 204 is coupled to the vertical axis housing structure 116 approximately 1600 mm above the platform 105 of the outrigger structure 104. In this example, the hydraulic ram 202 second pin and bracket 205 is coupled to the platform 105 of the outrigger structure 104 approximately 1500 mm away from the nearside of the vertical axis housing structure 116 when the vertical axis housing structure 116 10 is aligned perpendicular to the platform 105 of the outrigger structure 104.

In this example, the vertical axis turbine 108 further comprises a turbine braking system.

The hydraulic ram 202 is configured to contract and extend, such that the vertical axis turbine 108 is pivoted about the pin 200 to displace the vertical axis turbine 108. A hydraulic ram system may be advantageous as it is easily automated and may allow for remote operation. Displacement of the vertical axis turbine 108 is configured to raise and/or lower the vertical axis turbine 108 into and/or out of the water.

In this example, the turbine braking system is configured to automatically engage during contraction/extension of the hydraulic ram 202.

In this example, the controller is further configured to monitor one or more operational parameters of the floating renewable power station and signal to the hydraulic ram 202 to contract to raise at least one turbine 108 out of the water in the event that the operational parameter exceeds a selected threshold. This may be advantageous as a safety precaution to ensure the turbine does not produce beyond its safety limits or in the event of a fault code.

In a first configuration, when the hydraulic ram 202 is extended, as seen in Figure 2A, the vertical axis housing structure 116 is arranged perpendicular to the platform 105 of the outrigger 104 and the plurality of vertical axis turbine blades 112 are displaced below the outrigger structure 104, such that in use during hydropower generation, the plurality of -31 -turbine blades 112 are at least partially submerged underwater. This configuration is used for hydropower generation.

During contraction of the hydraulic ram 202, as seen in Figure 2B, the vertical axis turbine 108 is displaced about the pin pivot 200, such that the vertical axis housing structure 116 5 is rotated towards the platform 105 of the outrigger structure 104 and a portion of the plurality of vertical axis turbine blades 112 are displaced above the outrigger structure 104.

When the hydraulic ram 202 is contracted, as seen in Figure 20, the vertical axis turbine 108 is displaced about the pin pivot 200, such that the vertical axis housing structure 116 is rotated towards the platform 105 of the outrigger structure 104 and the plurality of vertical axis turbine blades 112 are displaced above the outrigger structure 104, such that the plurality of turbine blades 112 are above the water level. This configuration may be used during installation, maintenance, or other periods of non-use.

The hydraulic ram 202 may then be extended again to return the vertical axis turbine 108 to the first configuration shown in Figure 2A.

Figure 3 shows an example floating renewable power station 100, such as the example floating renewable power station of Figures 1 to 2, comprising two adjustable vertical axis turbines 108. In the example shown, each adjustable vertical axis turbine 108 is located on an outrigger structure 104 arranged starboard and portside of a central vessel 102. An example adjustable turbine is shown in more detail in Figures 4 and 5.

The adjustable vertical axis turbines 108 comprise a maximum turbine span 304 and a minimum turbine span 302.

The displacement of the vertical axis turbine blades 112 relative to the vertical axis turbine shaft 110 is configured to be adjustable, such that the diameter of the turbine span is adjustable. In the example shown, the diameter of the turbine span is configured to be adjusted by extending and/or contracting the horizontal adjustable struts 114. In the example shown, the diameter of the turbine span is configured to be adjustable to the maximum turbine span 304, the minimum turbine span 302, and a plurality of intermediate diameters of turbine span between the maximum 304 and minimum 302 turbine spans.

-32 -In this example, the diameter of the maximum turbine span 304 is configured to be less than the displacement of the pontoon 106 from the vessel 102, such that all possible diameters turbine span are configured to fit underneath the outrigger structure 104, between the vessel 102 and the pontoon 106.

Increasing the diameter of the turbine span is configured to increase the amount of electricity generated from hydropower relative to using a reduced turbine span diameter under the same operating conditions.

In use, increasing the diameter of the turbine span increases the 'swept area' of the turbine 108, thereby increasing the amount of electricity generated from hydropower relative to 10 using a reduced turbine span diameter under the same operating conditions.

In use, the diameter of the turbine span may be adjusted in response to one or more operational parameters. In this example, the floating renewable power station 100 further comprises a controller configured to obtain an indication of one or more operating parameters of at least one of the vertical axis turbines 108 and to adjust the diameter of the turbine spans in the event that the indication of the operating parameter exceeds or is less than a selected threshold. In this example, the operational parameters include, but are not limited to, water flow speed and/or power output. For example, in the event of overproduction, the diameter of the turbine may be reduced to limit the production profile of the renewable power station; and/or in the event of greater power demand than production, the diameter of the turbine span may be increased to increase the production profile of the renewable power station. Similarly, in the event that the water flow rate reduces, for example due to reduced tidal currents, the diameter of the turbine span may be increased to increase the production profile of the renewable power station. This may allow the turbine to automatically adapt to the variable profile of the environment, including variable water flow profiles.

Figure 4 shows an example adjustable turbine 108 for use in a floating renewable power station such as the example floating renewable power station 100 of Figures 1 to 3.

The vertical axis turbine 108 comprises a vertical axis turbine shaft 110, a plurality of vertical axis turbine blades 112, and a plurality of horizontal struts 114. The plurality of -33 -horizontal struts 114 are arranged perpendicular to the vertical axis turbine shaft 110 and are coupled between the vertical axis turbine shaft 110 and the plurality of vertical axis turbine blades 112. In this example, the adjustable turbine 108 comprises four identical turbine blades 112, each coupled to the turbine shaft 110 by a pair of identical horizontal 5 adjustable struts 114. Each vertical axis turbine blade 112 is arranged such that the wide face of the vertical axis turbine blade 112 is perpendicular to the horizontal struts 114. The horizontal adjustable struts 114 are arranged in a cross-shape, wherein the turbine shaft 110 is located at the centre of the cross. Each vertical axis turbine blade 112 comprises a plurality of internal support struts 408 arranged in a grid like structure, surrounded by a 10 tapered hydrofoil shell. An example vertical axis turbine blade is shown in more detail in Figure 7.

The plurality of horizontal adjustable struts 114 comprise a fixed portion 402 having a longitudinal axis, and a moveable portion 404. Two example adjustable horizontal strut configurations are shown in more detail in Figure 5A and 5B. At least a portion of the moveable portion 404 of horizontal adjustable strut 114 is disposed within the fixed portion 402 in a telescopic arrangement. In this example, the fixed portion 402 of each horizontal adjustable strut 114 is coupled to the turbine shaft 110 and the moveable portion 404 of each horizontal adjustable strut 114 is coupled to a vertical axis turbine blade 112 via a blade connector plate 406. An example blade connector plate is shown in more detail in Figures 6A and 6B.

Each pair of identical horizontal struts 114, including a pair of blade connector plates 406, are vertically displaced opposite to each other, parallel to the longitudinal axis of the vertical axis turbine blade 112, such that each pair of blade connector plates 406 is coupled to the top and bottom of a vertical axis turbine blade 112.

The diameter of the turbine span is configured to be adjusted by moving the movable portion 404 of each horizontal adjustable strut 114 in a direction parallel to the longitudinal axis of the fixed portion 402. In this example, the fixed portion 402 and the movable portion 404 of the horizontal adjustable strut 114 are configured to extend and/or contract in a telescopic arrangement.

-34 -In use, the diameter of the turbine span is configured to be adjusted by extending the movable portion 404 of each horizontal adjustable strut 114 in a direction parallel to the longitudinal axis of the fixed portion 402 and away from the vertical axis turbine shaft 110. This causes the horizontal adjustable strut 114 to extend by reducing the overlapping 5 portion of the movable portion 404 with the fixed portion 402 of the horizontal adjustable strut 114 in the telescopic arrangement, and increasing the portion of the movable portion 404 that protrudes from the fixed portion 402 of the horizontal adjustable strut 114 in the telescopic arrangement. As the moveable portion 404 is coupled to the turbine blade 112 via the blade connector plate 406, this thereby increases the displacement of the vertical 10 axis turbine blades 112 relative to the vertical axis turbine shaft 110, and thus increases the diameter of the turbine span.

In use, increasing the diameter of the turbine span increases the 'swept area of the turbine 108, thereby increasing the amount of electricity generated from hydropower relative to using a reduced turbine span diameter under the same operating conditions.

To reduce the diameter of the turbine span, the movable portion 404 of each horizontal adjustable strut 114 is moved in a direction parallel to the longitudinal axis of the fixed portion 402 and towards the vertical axis turbine shaft 110. This causes the horizontal adjustable strut to contract such that an increasing portion of the movable portion 404 of the horizontal adjustable strut 114 is withdrawn within the fixed portion 402 to increase the overlapping section within the telescopic arrangement.

Figure 5A shows an example horizontal adjustable strut 114 configuration for an adjustable turbine, such as the vertical axis turbine 108 of Figures 1 to 4. In this example, a turbine blade 112 is coupled between a pair of identical horizontal adjustable struts 114. Each pair of identical horizontal struts 114 are vertically displaced opposite to each other, parallel to the longitudinal axis of the vertical axis turbine blade 112, such that each pair of horizontal adjustable struts 114 is arranged at the top and bottom of a vertical axis turbine blade 112.

Each vertical axis turbine blade 112 is arranged such that the wide face of the vertical axis turbine blade 112 is perpendicular to the horizontal struts 114. Each vertical axis turbine blade 112 comprises a plurality of internal support struts 408 arranged in a grid like -35 -structure, surrounded by a tapered hydrofoil shell. An example vertical axis turbine blade is shown in more detail in Figure 7.

The plurality of horizontal adjustable struts 114 comprise a fixed portion 402 having a longitudinal axis, and a moveable portion 404. At least a portion of the moveable portion 5 404 of horizontal adjustable strut 114 is disposed within the fixed portion 402 in a telescopic arrangement. In this example, the fixed portion 402 of each horizontal adjustable strut 114 is coupled to the turbine shaft 110 and the moveable portion 404 of each horizontal adjustable strut 114 is coupled to a vertical axis turbine blade 112 via a blade connector plate 406. An example blade connector plate is shown in more detail in Figures 6A and 10 6B.

The fixed portion 402 of the horizontal adjustable strut comprises a plurality of apertures 502 arranged as a set. The plurality of apertures 502 are located at the end of the fixed portion 402 of the horizontal adjustable strut 114 within the overlap region of the moveable portion 404 in the telescopic arrangement. The moveable portion 404 comprises a plurality of sets of apertures 504, identical to the set of apertures 502 of the fixed portion 402.

In this example, the fixed portion 402 of the horizontal adjustable strut 114 is configured to receive the moveable portion 404 of the horizontal adjustable strut 114 as a telescopic insert. In other examples, the movable portion 404 of the horizontal adjustable strut 114 may be configured to receive the fixed portion 402 of the horizontal adjustable strut 114 as a telescopic insert.

The plurality of sets of apertures 504 of the moveable portion 404 are configured to align with the set of apertures 502 of the fixed portion 402 within the overlap region of the fixed portion 402 and moveable portion 404 in the telescopic arrangement. The plurality of apertures of the moveable portion 404 and the fixed portion 402 are configured to receive a bolt.

In use, at least one of the plurality of sets of apertures 504 of the moveable portion 404 are configured to align with the set of apertures 502 of the fixed portion 402 in a position, as indicated by the set of aligned apertures 506. As the diameter of the turbine span is adjusted and the moveable portion 404 is extended/contracted relative to the fixed portion -36 - 402 in the telescopic arrangement, the at least one set of apertures 504 of the moveable portion 404 which align with the set of apertures 502 of the fixed portion 402 changes.

The diameter of the turbine span is reversibly secured by passing bolts through the set of aligned apertures 506 between the fixed portion 402 and the moveable portion 404 of the 5 horizontal adjustable strut 114.

To adjust the diameter of the turbine span, the bolts are removed and the moveable portion 404 of each horizontal adjustable strut 114 is moved in a direction parallel to the longitudinal axis of the fixed portion 402 within the telescopic arrangement to the desired length, such that an alternative set of the plurality of sets of apertures 504 of the moveable portion 404 align with the set of apertures 502 of the fixed portion 402. The bolts are then reversibly replaced through the new set of aligned apertures 506.

Each vertical axis turbine blade 112 is arranged such that the wide face of the vertical axis turbine blade 112 is perpendicular to the horizontal struts 114. Each vertical axis turbine blade 112 comprises a plurality of internal support struts 408 arranged in a grid like structure, surrounded by a tapered hydrofoil shell. An example vertical axis turbine blade is shown in more detail in Figure 7.

The plurality of horizontal adjustable struts 114 comprise a fixed portion 402 having a longitudinal axis, and a moveable portion 404. At least a portion of the moveable portion 404 of horizontal adjustable strut 114 is disposed within the fixed portion 402 in a telescopic arrangement. In this example, the fixed portion 402 of each horizontal adjustable strut 114 is coupled to the turbine shaft 110 and the moveable portion 404 of each horizontal adjustable strut 114 is coupled to a vertical axis turbine blade 112 via a blade connector plate 406. An example blade connector plate is shown in more detail in Figures 6A and -37 -6B.

Each adjustable horizontal strut 114 of Figure 58 further comprises a hydraulic ram system 506. In the example shown, the hydraulic ram system 506 comprises two hydraulic actuators 508 arranged parallel to the longitudinal axis within the moveable portion 404 of the horizontal adjustable strut 114. In other examples, the ram system 506 may instead comprise piezoelectric actuators. At one end, the pair of hydraulic cylinders 508 are coupled to a fix bracket 510 within the fixed portion 402 of the horizontal adjustable strut 114. At the other end, the pair of hydraulic cylinders 508 are coupled to a hydraulic actuator 512 arranged on the blade connector plate 406.

The hydraulic ram system 506 is configured to extend and/or contract the horizontal adjustable strut by moving the movable portion 404 of the horizontal adjustable strut 114 in a direction parallel to the longitudinal axis of the fixed portion 402, such that the movable portion 404 of the horizontal adjustable strut 114 is configured to extend and/or contract in a telescopic arrangement from the fixed portion 402.

In this example, the position of the fix bracket 510 is arranged such that when the hydraulic cylinders 508 are fully contracted, the moveable portion of the horizontal adjustable strut 114 is fully withdrawn inside the fixed portion 402 of the horizontal adjustable strut 114 such that the fixed portion 402 of the horizontal adjustable strut 114 contacts the blade connector plate 406.

In use, the hydraulic actuator 512 causes the hydraulic cylinders 508 of the hydraulic ram system 506 to extend. This causes the horizontal adjustable strut to extend by moving the movable portion 404 of the horizontal adjustable strut 114 in a direction parallel to the longitudinal axis of the fixed portion 402, such that an increasing portion of the movable portion 404 of the horizontal adjustable strut 114 protrudes from the fixed portion 402 in a telescopic arrangement. As the moveable portion 404 is coupled to the turbine blade 112, this thereby increases the displacement of the vertical axis turbine blades 112 relative to the vertical axis turbine shaft 110, and thus increases the diameter of the turbine span.

In use, increasing the diameter of the turbine span increases the 'swept area' of the turbine 108, thereby increasing the amount of electricity generated from hydropower relative to -38 -using a reduced turbine span diameter under the same operating conditions.

To reduce the diameter of the turbine span, the hydraulic actuator 512 causes the hydraulic cylinders 508 of the hydraulic ram system 506 to contract. This causes the horizontal adjustable strut to contract by moving the movable portion 404 of the horizontal adjustable strut 114 in a direction parallel to the longitudinal axis of the fixed portion 402, such that an increasing portion of the movable portion 404 of the horizontal adjustable strut 114 is withdrawn to overlap with the fixed portion 402 in a telescopic arrangement.

Figures 6A and 6B show an example turbine blade 122 and blade connector plate 406 of a vertical axis turbine, such as the vertical axis turbine 108 of Figures Ito 5.

The vertical axis turbine blade 112 shown in this example comprises a plurality of support struts 408. The support struts 408 are arranged both in parallel and perpendicular directions relative to the longitudinal axis of the vertical axis turbine blade 112. The vertical axis turbine blades 112 typically comprise a hydrodynamic shell (not shown) that surrounds the plurality of support struts 408 to form a hydrofoil turbine blade, for example as seen in Figures 4 and 5.

The vertical axis turbine blade further comprises a pair of horizontal end plates 612 located at the top and bottom end of the turbine blade 112, coupled to at least a portion of the plurality of support struts 408. The horizontal end plates 612 are perpendicular to the longitudinal axis of the turbine blade 112.

In this example, the horizontal end plates 612 located at the top and bottom end of the turbine blade 112 each comprise a track 602. The track 602 is a straight track. In this example, the track is arranged along the chord line of the turbine blade 112, wherein the chord line is defined as the straight line joining the leading edge to the trailing edge of the hydrofoil cross-section of the vertical turbine blade 112. The track 602 has a T-shape cross section wherein the base of the T-shape is coupled to the horizontal end plate 612.

The horizontal end plates 612 also comprise a plurality of apertures 605. In this example, the plurality of apertures 605 are arranged along the track 602. The vertical axis turbine blade 112 further comprises a plurality of securing struts 610 coupled between the end -39 -plate 612 and a support strut 408, wherein the securing struts 610 are aligned with the plurality of apertures 605 along the horizontal end plate 612.

The blade connector plates 406 are shaped according to the cross section of the hydrofoil shell (not shown) of the vertical axis turbine blade 112. In this example, the blade connector plate 406 has a substantially teardrop shape, wherein the longitudinal axis of the teardrop-shape blade connector plate 406 is aligned with the cord line of the turbine blade 112. The blade connector plate 406 further comprises a protrusion 614 along one edge of the blade connector plate 406 perpendicular to the longitudinal axis of the teardrop-shape blade connector plate 406.

Furthermore, the blade connector plate 406 comprises a slot 604. The slot 604 extends along the longitudinal axis of the teardrop-shape blade connector plate 406 on the inward facing side of the blade connector plate 406. In this example, the slot 604 has a T-shape cross section.

The blade connector plate 406 also comprises a plurality of apertures 606. In this example, 15 the plurality of apertures 606 are aligned along the slot 604 The plurality of support struts 408 of the vertical axis turbine blade 112 are configured to be load bearing.

The slot 604 on the blade connector plate 406 is configured to receive the track 602 of the vertical axis turbine blade 112. In this example, the track 602 has a T-shaped cross section 20 and the slot 604 is configured to receive the 1-shape cross section of the track 602.

The plurality of apertures 605 of the horizontal end plate 612 are configured to align with the plurality of apertures 606 of the blade connector plate 406. In this example, the aligned apertures 605 and 606 and the securing struts 610 of the horizontal end plate 612 are configured to receive a bolt 608.

The blade connector plate 406 is configured to reversibly attach to a plurality of different types of vertical axis turbine blades 112, wherein different types of vertical axis turbine blades comprise different sizes and/or shapes of vertical axis turbine blades. In this -40 -example, the blade connector plate 406 is configured to receive any vertical axis turbine blade 112 comprising a track 602 configured to be received by the slot 604 of the blade connector plate 406. In some examples, the plurality of different types of vertical axis turbine blades 112 configured to attach to the blade connector plate 406 may have substantially the same chord length as the longitudinal axis of the blade connector plate 406.

In this example, each blade connector plate 406 is configured to attach to a horizontal strut 114 of a vertical axis turbine 108, for example as seen in Figures 4 and 5. In this example, the blade connector plate 406 is configured to extend from a horizontal strut 114 of a vertical axis turbine 108 at the protrusion 614 along the blade connector plate 406 perpendicular to the longitudinal axis. In some examples, each blade connector plate 406 may be integral within each horizontal strut 114 of a vertical axis turbine 108, for example the horizontal strut 114 may be machined/cast in a single piece, comprising a blade connector plate 406. In some examples, wherein the vertical axis turbine 108 has an adjustable turbine span, for example as seen in Figures 4 and 5, each blade connector plate 406 may be integral within the moveable portion 404 of the horizontal strut 114 of a vertical axis turbine 108, for example the movable portion 404 of the horizontal strut 114 may be machined/cast in a single piece, comprising a blade connector plate 406.

In use, the tracks 602 arranged on the top and bottom end plates 612 of a turbine blade 112 are aligned with the slots 604 of a pair of vertically displaced blade connector plates 406. The turbine blade 112 is then moved parallel along the longitudinal axis of the pair of blade connector plates 406 such that the tracks 602 reversibly engage with the slots 604 of both blade connector plates 406.

The turbine blade 112 is then moved along the slots 604 of both blade connector plates 406 until the plurality of apertures 606 on the blade connector plates 406 are aligned with the plurality of apertures 605 on the end plates 612 of the turbine blade 112. In the example shown in Figure 6B, the turbine blade is reversibly secured by bolting 608 each blade connector plate to the turbine blade 112 through the plurality of aligned apertures 606 and 605. In this example, the bolts 608 pass into the securing struts 610 of the turbine blade 112. -41 -

To change the turbine blade 112, the bolts 608 are removed from the plurality of aligned apertures 606 and 605 and the blade 112 is moved along the slots 604 of the blade connector plates 406 until the tracks 602 disengage. A replacement blade 112 may then be attached as described above, wherein the replacement blade 112 comprises a track 602 complementary to the slots 604 of the blade connector plates 406.

Figure 7 shows an example vertical axis turbine blade 112, for use in a vertical axis turbine such as the example vertical axis turbines 108 of Figures Ito 6.

The example vertical turbine blade 112 comprises a proximal end 702 and a distal end 704. The turbine blade 112 has a teardrop-shaped cross section between the proximal end 702 and the distal end, wherein the teardrop shape is parameterised by a length and a width. In the example shown, the teardrop shape cross section has a length of 1000 mm and a width of 150 mm at the proximal end 702 and the distal end 704. In other examples, other sizes of vertical axis turbine blade may be used. The vertical turbine blade 112 further comprises a portion 706, between the proximal end 702 and the distal end 704, with an enlarged teardrop-shaped cross section relative to the tear-drop shaped cross section at the proximal end 702 and the tear-drop shaped cross section at the distal end 704. The enlarged cross section is enlarged in length and width relative to the cross section at the proximal end 702 and distal end 704. In some examples, the enlarged cross section may be enlarged proportionally relative to the cross section at the proximal end 702 and distal end 704. In the example shown, the enlarged teardrop shape cross section of the enlarged portion 706 is enlarged by 10 % relative to the cross section at the proximal end 702 and distal end 704, such that the enlarged cross section has a length of 1100 mm and a width of 165 mm. In other examples, other sizes of vertical axis turbine blade may be used.

In this example, the portion 706 with an enlarged cross section is equidistant from the 25 proximal end 702 and the distal end 704.

The vertical turbine blade 112 further comprises a pair of horizontal end plates 612 located at the proximal 702 and distal 704 ends of the turbine blade 112. In the example shown, the vertical height of the vertical axis turbine blade 112 from the horizontal end plate 612 at the proximal end 702 to the horizontal end plate 612 at distal 704 end of the turbine -42 -blade 112 is 2550 mm. In other examples, other sizes of vertical axis turbine blade may be used, for example, in some examples the vertical height of the vertical axis turbine blade 112 may be within a range of 500 mm to 10 m.

In this example, the horizontal end plates 612 each comprise a track 602. The track 602 is a straight track and is aligned with the chord line of the turbine blade 112 profile, wherein the chord line is defined as the straight line joining the leading edge to the trailing edge of the hydrofoil teardrop-shaped cross-section of the vertical turbine blade 112. In this example, the track 602 has a T-shaped cross section.

The vertical turbine blade 112 also comprises two tapered portions 708 arranged between 10 the proximal end 702 and the distal end 704, either side of the portion with an enlarged cross section 706. The tapered portions 708 graduate the cross-section between the portion with an enlarged cross section 706 and the proximal end 702 or distal end 704.

The vertical turbine blade 112 further comprises a plurality of surface coatings including a base coat, a primer coat, a fie coat, and an antifouling top coat. In the example shown, the 15 base coat used is epoxy filler.

In this example, the track 602 of the vertical axis turbine blade 112 is configured to be received by a slot of a blade connector plate 406 of a vertical axis turbine 108.

The plurality of surface coatings are configured to resist wear, corrosion, and/or fouling of the turbine blade 112.

In use, the turbine blades 112 may have improved hydrodynamic performance relative to conventional straight vertical axis turbine blades, for example in H-Darrieus or squirrel cage Darrieus vertical axis turbine arrangements.

Figure 8 shows an example floating renewable power station, such as the example floating renewable power station 100 of Figures 1 to 7, further comprising two pairs of venturi ducting plates 800. In this example, the venturi ducting plates 800 have a curved shape, comprising a convex edge. Each pair of venturi ducting plates 800 is arranged such that the convex edge of a first ducting plate 800A is opposite the convex edge of a second -43 -ducting plate 800B. In this example, the pairs of venturi ducting plates 800 are located starboard and portside of the vessel 102, wherein at least a portion of the pair of venturi ducting plates 800 are underneath the outrigger structures 104. In this example, the first 800A and second 800B ducting plates within a pair 800 are displaced based on the width of the outrigger structure 104, such that at least a portion of the first ducting plate 800A is arranged underneath the proximal edge of the outrigger structure 104 adjacent to the vessel 102, whereas the second ducting plate 800B is arranged such that at least a portion of the plate is underneath the distal edge of the outrigger structure 104 from the vessel 102, adjacent to the pontoon 106. Each hydropower turbine 108 is arranged between a pair of venturi ducting plates 800. The longitudinal axis of the venturi ducting plates 800 is arranged parallel to the longitudinal axis of the vessel 102. In this example, the venturi ducting plates 800 extend from underneath the outrigger structure 104 to approximately in line with the stern 101 of the vessel 102.

In this example, each venturi ducting plate 800A or 800B is supported underneath the outrigger structure 104 by a support structure 802 which is coupled between each ducting plate 800 and the platform 105 of the outrigger structure 104. The distal end of each venturi ducting plates 800 furthest displaced from the outrigger structure 104 is additionally tethered 803 to the support structure 802. In this example, the tether 803 is a metal rope, for example a steel rope. In other examples, the tether 803 may be another material, for example rope, wood, or metal.

In this example, the floating renewable power station 100 further comprises two bars 804 that extend from the stern 101 of the vessel 102 both starboard and portside. The bar 804 comprises a portion that extends from the stern 101, parallel to the edge of the outrigger structure 104, and a portion that extends from the pontoon 106, parallel to the longitudinal axis of the vessel 102.

The venturi ducting plates are configured to be at least partially submerged in water. Each pair of venturi ducting plates 800 is configured to increase the water flow velocity through the associated turbine 108.

In use, increasing the water flow velocity through the hydropower turbine 108 may increase -44 -the power generated by the hydropower turbine 108. Thus, the venturi ducting plates 800 may increase the power generation and efficiency of the floating renewable power station 100.

The bar 804 is configured to approximately encompass the venturi ducting plates 800, and in some examples, the bar 804 may function to protect the venturi ducting plates 800 from damage. For example, where the venturi ducting plates 800 are submerged, the bar 804 be visible to indicate the area footprint of the floating renewable power station 100, such that other vessels do not get too close and damage the protruding venturi ducting plates 800. -45 -

Embodiments of the disclosure are set out in the following numbered clauses.

1 A floating renewable power station comprising: a vessel, comprising at least one outrigger structure; and at least one vertical axis turbine for generating power from hydropower, coupled to the outrigger structure; and a controller configured to export power to an onshore power network.

The floating renewable power station of clause 1, further comprising a pivot means configured to displace the vertical axis turbine.

The floating renewable power station of clause 2, wherein the displacement of the vertical axis turbine by the pivot means is configured to raise and/or lower the vertical axis turbine into and/or out of the water.

The floating renewable power station of clause 2 or 3, wherein the pivot means is configured to raise and/or lower the vertical axis turbine relative to the outrigger structure.

The floating renewable power station of clause 2 to 4, wherein the at least one vertical axis turbine comprises a plurality of blades, and wherein the pivot means is raised above the outrigger structure and configured such that when the at least one vertical axis turbine pivots all of the plurality of blades of the vertical axis turbine are lifted out of the water.

The floating renewable power station of clause 2 to 5, wherein the pivot means comprises a pin providing a pivot for the vertical axis turbine relative to the outrigger, and a hydraulic ram configured to pivot the vertical axis turbine about the pin to displace the vertical axis turbine. 2. 4 6 -46 -

7 The floating renewable power station of any of the preceding clauses, wherein the controller is further configured to load shed in the event that power demand exceeds the export power level.

8 The floating renewable power station of any of the preceding clauses, wherein the controller is configured to shut down at least one of the vertical axis turbines in the event that power produced exceeds a selected threshold and/or power demand.

9 The floating renewable power station of any of the preceding clauses, wherein the controller is further configured to vary the proportion of produced power used by components of the floating renewable power station including the controller.

10. The floating renewable power station of any of the preceding clauses, further comprising at least one solar panel for generating power from solar energy.

11. A floating renewable power station comprising: a turbine for generating power from hydropower; and at least one solar panel for generating power from solar energy; further comprising a controller configured to export power to an onshore power network and vary the proportion of energy from solar energy and from hydropower delivered to the onshore power network.

12. The floating renewable power station of clause 11 wherein a proportion of energy generated from at least one of (i) solar energy and (ii) hydropower is routed to power components of the floating renewable power station including the controller.

13. The floating renewable power station of clause 12 wherein the controller is further configured to vary the proportion of energy from solar energy and/or from hydropower used by the components of the floating renewable power station including the controller. -47 -

14. The floating renewable power station of clauses 11 to 13, further comprising backup power means configured to deliver power in the event that the amount of available power from at least one of solar energy and hydropower falls below a selected threshold.

15. The floating renewable power station of clauses 11 to 14 wherein the backup power means further comprises at least one of (i) a fuel generator and (ii) a battery.

16 The floating renewable power station of clauses 11 to 15 wherein the controller is configured to monitor power demand of the onshore power network and power exported to the onshore power network by the floating renewable power station, and wherein the controller is further configured to load shed in the event that the power demand exceeds the power exported.

17 The floating renewable power station of clauses 11 to 16, wherein the controller is further configured to monitor one or more operational parameters of the floating renewable power station; and wherein the floating renewable power station further comprises a turbine braking system, coupled to the controller, configured to slow and/or stop the at least one turbine in the event that the operational parameter exceeds a selected threshold.

18 The floating renewable power station of clause 17 wherein the operational parameters include at least power exported to the onshore power network by the floating renewable power station, and power demand of the onshore power network, and wherein the turbine braking system is configured to slow and/or stop the at least one turbine in the event that the power exported exceeds the power demand.

19. The floating renewable power station of clause 17 or 18 wherein the operational parameters include at least power produced by the at least one turbine and wherein -48 -the turbine braking system is configured to slow and/or stop the at least one turbine in the event that the power produced by the at least on turbine exceeds a selected threshold.

A floating renewable power station comprising: at least one turbine for generating power from hydropower; a plurality of sensors, configured to obtain an indication of one or more operational parameters of the renewable power station; a controller, configured to receive the indication of one or more operational parameters from the plurality of sensors; and a turbine braking system, coupled to the controller, configured to slow and/or stop the at least one turbine in the event that the indication of the operating parameter exceeds a selected threshold.

21 The floating renewable power station of clause 20, further comprising a communication module, coupled to the controller, configured to send the indication of one or more operational parameters to a remote device; and wherein the turbine braking system is configured to slow and/or stop the at least one turbine in response to receiving a signal from the remote device in the event that the indication of the operational parameter exceeds a selected threshold.

22. The floating renewable power station of clause 20 or 21, wherein the turbine for generating power from hydropower is a vertical axis turbine.

23. The floating renewable power station of clauses 20 to 22, further comprising at least one solar panel for generating power from solar energy.

24. The floating renewable power station of clauses 20 to 23, wherein the one or more operational parameters comprise at least one of temperature, humidity, inclination, position, water flow speed, turbine vibration, turbine speed. -49 -

25. The floating renewable power station of any of clauses 20 to 24, further comprising an uninterrupfible power supply, configured to power safety critical components including at least the turbine braking system.

26. The floating renewable power station of clause 25 wherein the uninterrupfible power supply comprises a battery and/or a fuel generator.

27. The floating renewable power station of Clauses 20 to 26, wherein the controller is configured to release the turbine braking system in the event that a second indication of the operating parameter is below a second selected threshold.

28. The floating renewable power station of any of clauses 20 to 27, wherein the communication module is further configured to receive signals from the remote device, and wherein the controller is configured to start-up and/or shut down a turbine in response to a signal received by the communication module from the remote device.

29. A vertical axis turbine for generating power from hydropower, comprising: a vertical axis turbine shaft; a plurality of vertical axis turbine blades; wherein the displacement of the vertical axis turbine blades relative to the vertical axis turbine shaft is configured to be adjustable, such that the diameter of the turbine span is adjustable.

The vertical axis turbine for generating power from hydropower of clause 29, further comprising a plurality of horizontal adjustable struts, the plurality of horizontal adjustable struts coupled between the vertical axis turbine shaft and the plurality of vertical axis turbine blades; wherein the diameter of the turbine span is configured to be adjusted by extending and/or contracting the horizontal adjustable struts.

-50 - 31. The vertical axis turbine for generating power from hydropower of clause 30, wherein the plurality of horizontal adjustable struts comprises a fixed portion having a longitudinal axis and a moveable portion, and wherein the diameter of the turbine span is configured to be adjusted by moving the movable portion of each horizontal adjustable strut in a direction parallel to the longitudinal axis of the fixed portion.

32. The vertical axis turbine for generating power from hydropower of clauses 30 to 31, wherein the fixed portion and the movable portion of the horizontal adjustable strut are configured to extend and/or contract in a telescopic arrangement.

33. The vertical axis turbine for generating power from hydropower of any of clauses 30 to 32, further comprising a hydraulic or piezoelectric ram system configured to extend and/or contract the horizontal adjustable struts.

34 The vertical axis turbine for generating power from hydropower of 29 to 33, further comprising a controller; wherein the controller is configured to obtain an indication of one or more operating parameters of the vertical axis turbine and to adjust the diameter of the turbine span in the event that the indication of the operating parameter exceeds or is less than a selected threshold.

35. The vertical axis turbine for generating power from hydropower of clause 34 wherein the operational parameters include at least one of water flow speed and/or power output.

36. A vertical turbine blade for generating power from hydropower comprising: a proximal end; a distal end; a teardrop-shaped cross section, parameterised by a length and a width; and -51 -a portion, between the proximal end and the distal end, with an enlarged teardrop-shaped cross section relative to the tear-drop shaped cross section at the proximal end and the tear-drop shaped cross section at the distal end.

37. The vertical turbine blade for generating power from hydropower of clause 36 wherein the portion with an enlarged cross section is equidistant from the proximal end and the distal end.

38. The vertical turbine blade for generating power from hydropower of clauses 36 to 37, wherein the enlarged cross section is enlarged in length relative to the cross section at the proximal end and distal end.

39. The vertical turbine blade for generating power from hydropower of clauses 36 to 38, wherein the enlarged cross section is enlarged in width relative to the cross section at the proximal end and distal end.

40. The vertical turbine blade for generating power from hydropower of clauses 36 to 39, further comprising at least one tapered portion, arranged between the portion with an enlarged cross section and the proximal end and/or distal end.

41. A vertical axis turbine for generating power from hydropower, comprising: a vertical axis turbine shaft; a plurality of struts, coupled to the vertical axis turbine shaft; and a plurality of vertical axis turbine blades, configured to be reversibly coupled to the plurality of struts; wherein the plurality of struts are configured to attach to a plurality of different types of vertical axis turbine blades.

42. The vertical axis turbine for generating power from hydropower of clause 41, wherein the different types of vertical axis turbine blades comprise different sizes and/or shapes of vertical axis turbine blades.

-52 - 43. The vertical axis turbine for generating power from hydropower of clauses 41 to 42, wherein each strut comprises a blade connector plate at one end, configured to reversibly attach to a plurality of different types of vertical axis turbine blades.

44. The vertical axis turbine for generating power from hydropower of clauses 41 to 43 wherein the plurality of vertical axis turbine blades further comprise at least one track, and wherein the plurality of struts further comprise a slot configured to receive the track of the vertical axis turbine blade.

45. The vertical axis turbine for generating power from hydropower of clauses 41 to 44 wherein the plurality of struts are configured to be adjustable in length.

46. The floating renewable power station of clauses 1 to 28, further comprising at least a pair of venturi ducting plates, configured to increase the water flow velocity through the at least one hydropower turbine.

47. A floating renewable power station comprising: at least one hydropower turbine; and at least a pair of venturi ducting plates, configured to increase the water flow velocity through the at least one hydropower turbine.

48. The floating renewable power station of clause 47, wherein the at least one hydropower turbine is a vertical axis hydropower turbine.

49. The floating renewable power station of clauses 47 or 48 wherein the venturi ducting plates are curved.

Claims

-53 -Claims 1 A vertical axis turbine for generating power from hydropower, comprising: a vertical axis turbine shaft; a plurality of vertical axis turbine blades; wherein the displacement of the vertical axis turbine blades relative to the vertical axis turbine shaft is configured to be adjustable, such that the diameter of the turbine span is adjustable, and a controller configured to obtain an indication of power output of the turbine and power demand, and wherein the controller is configured to adjust the diameter of the turbine span based on the indication of the power output and the power demand.
2 The vertical axis turbine for generating power from hydropower of claim 1, further comprising a plurality of horizontal adjustable struts, the plurality of horizontal adjustable struts coupled between the vertical axis turbine shaft and the plurality of vertical axis turbine blades; wherein the diameter of the turbine span is configured to be adjusted by extending and/or contracting the horizontal adjustable struts.
3 The vertical axis turbine for generating power from hydropower of claim 2, wherein the plurality of horizontal adjustable struts comprises a fixed portion having a longitudinal axis and a moveable portion, and wherein the diameter of the turbine span is configured to be adjusted by moving the movable portion of each horizontal adjustable strut in a direction parallel to the longitudinal axis of the fixed portion.
4 The vertical axis turbine for generating power from hydropower of claims 2 to 3, wherein the fixed portion and the movable portion of the horizontal adjustable strut are configured to extend and/or contract in a telescopic arrangement.

The vertical axis turbine for generating power from hydropower of any of claims 2 to 4, further comprising a hydraulic or piezoelectric ram system configured to extend and/or contract the horizontal adjustable struts.

-54 - 6 The vertical axis turbine for generating power from hydropower of any preceding claim, further comprising a controller; wherein the controller is configured to obtain an indication of one or more operating parameters of the vertical axis turbine and to adjust the diameter of the turbine span in the event that the indication of the operating parameter exceeds or is less than a selected threshold.

7 The vertical axis turbine for generating power from hydropower of claim 6 wherein the operational parameters include at least one of water flow speed and/or power output.