DK181364B1

DK181364B1 - Device for supplying electricity to a unit in a vessel

Info

Publication number: DK181364B1
Application number: DKPA202101266A
Authority: DK
Inventors: Vejlgaard-Laursen Morten; Tomaszewski Perez Amrei; Zeuthen Jacob; Skoudal Løth Christian
Original assignee: A P Moeller Mærsk As
Priority date: 2021-12-22
Filing date: 2021-12-22
Publication date: 2023-09-04
Also published as: DK202101266A1; DK181364B9; WO2023117024A1

Abstract

Disclosed is an apparatus for supplying electricity to a device of a vehicle. The apparatus comprises an electricity generation system comprising a fuel inlet for receiving fuel, an electricity generator for electrochemically generating electricity using the fuel, an electrical outlet for supplying the electricity to the device, a waste fluid outlet for discharging waste fluid from the electricity generation system, and a carbon dioxide outlet for discharging carbon dioxide generated by the electricity generation system. The carbon dioxide outlet is separate from the waste fluid outlet. The apparatus further comprises a carbon dioxide capture system having a carbon dioxide inlet fluidically connectable or connected to the carbon dioxide outlet, whereby the carbon dioxide capture system is for receiving and storing the carbon dioxide, and a cooling system having a waste fluid inlet fluidically connectable or connected to the waste fluid outlet. The cooling system is configured to use thermal energy from the waste fluid to cool coolant to be supplied to the carbon dioxide capture system for use in cooling the carbon dioxide in the carbon dioxide capture system. Vehicles comprising the apparatus, and method for generating electricity for supplying to a device of a vehicle, are also disclosed.

Description

DK 181364 B9 1

TECHNICAL FIELD

[0001] The present invention relates to an apparatus for supplying electricity to a device of a vehicle, a method for generating electricity for supplying to a device of a vehicle, and —avehicle comprising the apparatus.

BACKGROUND

[0002] Vehicles often employ internal combustion engines (ICEs) to generate propulsion and optionally electrical energy for operating the vehicle. Typically, though, internal combustion engines rely on combusting non-renewable fuel (e.g. heavy fuel oil, diesel, or gasoline) to generate the propulsion and/or electricity. The combustion of non- renewable fuels contributes to the level of carbon dioxide in the atmosphere, sometimes referred to as “carbon emissions”. There is a desire to power vehicles in a way which releases less carbon dioxide into the atmosphere, e.g. to power vehicles in a substantially “carbon neutral” manner (e.g. a state of net zero carbon dioxide emissions).

[0003] In place of (or in addition to) internal combustion engines, some vehicles employ fuel cells to generate electricity, which in turn can power a motor and/or other systems of a vehicle requiring power. The operation of fuel cells typically results in less carbon dioxide being emitted into the atmosphere compared with internal combustion engines powered by non-renewable fuels because, for example, the operation of fuel cells relies on hydrogen (Hz) and/or there is a higher degree of energy conversion achieved in a fuel cell compared with an internal combustion engine. However, in some cases the operation of a fuel cell still generates carbon dioxide which is released into the atmosphere.

[0004] Although fuel cells often do not employ heavy fuel oil, diesel, or gasoline to generate the electricity, many still rely on fuels that have been generated from non- renewable sources (e.g. methanol produced from natural gas). While these systems may employ “renewable” fuels (e.g. fuels produced from renewable sources), the generation of renewable fuels often requires carbon-based feedstocks. Such carbon-based feedstocks may derive from non-renewable sources (such that the operation of a fuel cell using that fuel is no longer considered to be “carbon neutral”), or renewable sources

DK 181364 B9 2 which are often more expensive and difficult to obtain. US 2012/0108117 A1 describes an apparatus for generating electricity required by an LNG (liquified natural gas) carrier which stores LNG, which is obtained by liquefying natural gas to ultra low temperature in a gas field, in an LNG storage tank and carries the stored LNG. The apparatus includes: a reformer reforming boil-off gas occurring in the LNG storage tank and producing synthetic gas; and a fuel cell generating electricity through an electrochemical reaction of the synthetic gas produced by the reformer.

[0005] Further, there is a need to reduce the power requirements of operating a vehicle (e.g. a need to make the vehicle more energy efficient) so that less fuel is consumed during operation of the vehicle. Also, there is a need to reduce noise pollution generated by operation of a vehicle, and/or to provide to vehicles energy generation systems having a longer usable lifetime.

SUMMARY

[0006] Examples of the present invention as described herein aim to address one or — more of the problems described hereinabove.

[0007] According to a first aspect of the present invention, there is provided an apparatus for supplying electricity to a device of a vehicle. The apparatus comprises an electricity generation system, the electricity generation system comprising a fuel inlet for receiving fuel, an electricity generator for electrochemically generating electricity using the fuel, an electrical outlet for supplying the electricity to the device, a waste fluid outlet for discharging waste fluid from the electricity generation system, and a carbon dioxide outlet for discharging carbon dioxide (CO.) generated by the electricity generation system, the carbon dioxide outlet separate from the waste fluid outlet. The apparatus further comprises a carbon dioxide capture system having a carbon dioxide inlet fluidically connectable or connected to the carbon dioxide outlet, whereby the carbon dioxide capture system is for receiving and storing the carbon dioxide, and a cooling system having a waste fluid inlet fluidically connectable or connected to the waste fluid outlet, wherein the cooling system is configured to use thermal energy from the waste fluid to cool coolant to be supplied to the carbon dioxide capture system for use in cooling the carbon dioxide in the carbon dioxide capture system.

DK 181364 B9 3

[0008] The apparatus captures the carbon dioxide by-product of electrochemically generating electricity from the fuel, thereby reducing carbon dioxide emissions from the apparatus, and in some examples from the vehicle, into the atmosphere. Further, capturing the carbon dioxide allows for later recycling of the carbon dioxide. For example, the carbon dioxide can later be processed to provide fuel, which in turn can be used in an apparatus as described herein in a substantially "carbon neutral” process. This is not only beneficial for the environment, but can also reduce the cost of operating a vessel, because operation of the apparatus provides the operator with a feedstock material (e.g.

CO») which can be used for the production of further fuel, thereby ameliorating the problems associated with obtaining renewable fuels in a substantially "carbon neutral” manner. Alternatively, the captured carbon dioxide can later be stored underground such that operation of the apparatus is a substantially “carbon negative” process. For example, where carbon dioxide is used to generate the fuel used by the apparatus, that carbon dioxide may be sourced biogenically, and the carbon dioxide generated through use of — the apparatus is subsequently sequestered.

[0009] Further, the apparatus makes use of waste thermal energy generated during the generation of electricity to cool coolant for cooling the carbon dioxide, thereby reducing the energy demands of the system for receiving and storing the carbon dioxide. Reducing the energy demands typically means that the vehicle is more cost-efficient to operate.

[0010] The fuel inlet is for receiving fuel. Optionally, the fuel inlet is fluidically connectable or connected to a fuel container for containing fuel, such as a fuel tank. Optionally, flow of fuel to the electricity generation system via the fuel inlet is controlled with one or more valves and/or pumps arranged between the fuel container and the fuel inlet.

[0011] The electricity generation system comprises the waste fluid outlet for discharging waste fluid from the electricity generation system. Optionally, in operation, one or more components of the electricity generation system generates thermal energy (heat) which is not used in the generation of electricity (e.g. the thermal energy is waste thermal energy). At least some of this thermal energy is discharged from the electricity generation system through the waste fluid; the waste fluid receives thermal energy from one or more components of the electricity generation system, and is discharged from the electricity generation system via the waste fluid outlet. Advantageously, this thermal energy is used

DK 181364 B9 4 by the cooling system to cool coolant, thereby reducing the energy demands of the apparatus such that the apparatus is more energy-efficient to operate.

[0012] Optionally, the waste fluid comprises water. Optionally, the electricity generation system is configured to generate water during use, wherein the water is waste water (e.g. the water is not used in the generation of electricity). Optionally, the electricity generation system is configured to generate water, supply thermal energy to the water (typically waste thermal energy — thermal energy not used in the generation of electricity) to provide heated water, and discharge the heated water via the waste fluid outlet.

[0013] The carbon dioxide outlet is separate from the waste fluid outlet. Optionally, the carbon dioxide outlet of the electricity generation system is a carbon dioxide outlet of the electricity generator, and the waste fluid outlet is a waste fluid outlet of the electricity generator. Optionally, the carbon dioxide outlet and the waste fluid outlet of the electricity generation system are downstream from the electricity generator. For example, carbon dioxide and waste fluid are discharged from the electricity generator in a single stream, and downstream of the electricity generator the carbon dioxide and waste fluid are separated by a separator (e.g. a condenser). The separated carbon dioxide is discharged from the carbon dioxide outlet of the electricity generation system, and the separate waste fluid is discharged from the waste fluid outlet of the electricity generation system.

[0014] Optionally the electricity generator comprises a fuel cell. In examples, the electricity generator is a fuel cell. Fuel cells as described herein typically provide higher energy conversion when generating electricity than internal combustion engines powered by non-renewable fuels.

[0015] Fuel cells as described herein are electrochemical cells which generate electricity through redox reactions. The fuel cell typically comprises an electrolyte sandwiched between an anode and a cathode. In use, the fuel cell receives an oxidant at the cathode (e.g. oxygen, O») via an inlet at the cathode side of the fuel cell, and a material to be oxidised at the anode (typically hydrogen, H) via another, separate inlet at the anode side of the fuel cell. For example, fuels other than pure hydrogen may be provided to the anode side of the fuel cell via the inlet. In such aspects, the hydrogen is used as the material to be oxidised by the fuel cell and the other compounds may not be substantially used by the fuel cell in generating electricity. For example, a gas comprising hydrogen

DK 181364 B9 along with nitrogen and/or carbon dioxide may be provided to the anode side of the fuel cell via the inlet.

[0016] The material to be oxidised is oxidised at the anode: in examples, cations and/or protons are conducted through the electrolyte to the cathode, and electrons are 5 conducted to the cathode via an electrical circuit, thereby generating electricity and providing it to the device. Water is generated at the cathode, and discharged from the fuel cell via an outlet at the cathode side of the fuel cell. In examples, the outlet of the fuel cell through which water is discharged is the waste fluid outlet of the electricity generation system for discharging waste fluid.

[0017] In other examples, anions are conducted from the cathode, through the electrolyte, to the anode, and electrons are conducted to the cathode via an electrical circuit, thereby generating electricity and providing it to the device. In these examples, water is generated at the anode, and discharged from the fuel cell via the outlet at the anode side of the fuel cell, along with any unreacted material received at the anode. In examples, the fluid discharged from the fuel cell via the outlet at the anode of the fuel cell comprises carbon dioxide and water, and the carbon dioxide and water are separated downstream of the fuel cell to provide a carbon dioxide stream discharged via the carbon dioxide outlet of the electricity generation system, and a waste water stream discharged via the waste fluid outlet of the electricity generation system.

[0018] Optionally, any excess hydrogen (e.g. any hydrogen which has not been used by the fuel cell to generate electricity), and any other compound which was received at the anode and not used by the anode, is discharged from the fuel cell via an outlet at the anode side of the fuel cell. This discharge is typically fluid, and can be referred to as a “stream”. Optionally, substantially all of the hydrogen provided to the fuel cell is oxidised at the anode, such that the stream is substantially free of hydrogen. Optionally, carbon dioxide is received at the anode, and discharged from the fuel cell via the outlet at the anode side of the fuel cell. For example, the discharge is a carbon dioxide stream (e.g. a stream comprising carbon dioxide). The outlet can be referred to as a fuel cell exhaust.

In other examples, carbon dioxide is not received by the fuel cell (for example, carbon dioxide generated in providing the hydrogen is separated from the fluid stream before the hydrogen is provided to the fuel cell). In these cases, substantially no carbon dioxide is discharged from the outlet at the anode side of the fuel cell. In some examples, where

DK 181364 B9 6 water is generated at the anode, the fuel cell exhaust is for discharging carbon dioxide and waste water from the fuel cell.

[0019] Optionally, the fuel cell exhaust and waste fluid outlet of the fuel cell are arranged apart from each other; they are separate. In examples, the fuel cell exhaust is arranged at the anode side of the fuel cell, and the waste fluid outlet is arranged at the cathode side of the fuel cell. In other examples, the fuel cell exhaust is an exhaust for discharging both carbon dioxide and waste fluid from the fuel cell. In these examples, the carbon dioxide and waste fluid are separated downstream to provide a carbon dioxide stream and a waste fluid stream, to be discharged from the carbon dioxide outlet and waste fluid outlet of the electricity generation system respectively.

[0020] Optionally, the outlet of the electricity generation system for discharging carbon dioxide is an outlet of the fuel cell. Optionally, the fuel cell exhaust is the carbon dioxide outlet of the electricity generation system, and is separate from a waste fluid outlet of the fuel cell. For example, the fuel cell exhaust is fluidically connectable or connected to the carbon dioxide capture system.

[0021] Optionally, oxygen is provided to the cathode of the fuel cell via the inlet at the cathode side as part of an oxygen-containing stream. The oxygen-containing stream optionally contains other components, such as nitrogen and/or carbon dioxide.

Optionally, the oxygen-containing stream is air, e.g. from the atmosphere surrounding the fuel inlet. That is, the inlet is an inlet for receiving air. The oxygen-containing stream, such as atmospheric air, typically has a carbon dioxide content which is less than the carbon dioxide stream discharged from the fuel cell. Atmospheric air typically comprises nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%), and other trace gases.

[0022] Optionally, the fuel cell comprises at least two outlets: the waste fluid outlet for discharging waste fluid (typically comprising water), and the carbon dioxide outlet for discharging carbon dioxide. Water is discharged from the fuel cell as part of, or substantially all of, a waste fluid stream; the carbon dioxide is discharged from the fuel cell as part of, or substantially all of, a carbon dioxide stream.

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[0023] The carbon dioxide stream may have a higher concentration of carbon dioxide than the waste fluid stream. The carbon dioxide stream typically has a carbon dioxide concentration greater than the carbon dioxide concentration of the oxygen-containing stream provided to the fuel cell via the inlet at the cathode side, e.g. of atmospheric air, eg. the carbon dioxide stream has a carbon dioxide concentration greater than atmospheric air.

[0024] The waste fluid stream may have a lower concentration of carbon dioxide than the carbon dioxide stream. For example, the waste fluid stream has a carbon dioxide concentration substantially the same as, or less than, the carbon dioxide concentration of the oxygen-containing stream provided to the fuel cell via the inlet at the cathode side, e.g. the waste fluid stream has a carbon dioxide concentration substantially the same as, or less than, atmospheric air. Optionally, the waste fluid stream is substantially free of carbon dioxide.

[0025] The term “fuel” as used herein typically refers to a composition from which hydrogen (Hz) can be generated for use by the fuel cell to generate electricity. Optionally, the fuel comprises one or more hydrocarbons, optionally one or more aliphatic hydrocarbons.

[0026] Optionally, the fuel comprises methanol, ethanol, dimethyl ether, methane, crude from a Fischer-Tropsch process, wax from a Fischer-Tropsch process, or a combination thereof. Optionally, the fuel comprises, consists essentially of, or consists of methanol.

[0027] Optionally, the fuel cell is a solid oxide fuel cell or a proton-exchange membrane fuel cell.

[0028] The electrical outlet of the electricity generation system is typically an electrical contact which is electrically connected or connectable to the device of the vehicle. The device of the vehicle is any device capable of receiving electricity and converting it to another form of energy. Optionally, the device is a capacitor, battery, motor, computer, heating system, or lighting system. Optionally, the electricity generation system comprises a fuel cell, and the fuel cell comprises the electrical outlet of the electricity generation system.

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[0029] Optionally, the electricity generation system comprises a reformer for receiving the fuel via the fuel inlet and for generating hydrogen from the fuel, wherein the fuel cell is fluidically connectable or connected to the reformer, and wherein the fuel cell is for receiving hydrogen from the reformer and generating the electricity using the hydrogen.

Advantageously, a reformer allows for the generation of hydrogen for supplying to the fuel cell in situ, e.g. on board a marine vessel during transit, obviating the need to store large amounts of hydrogen on board which would otherwise reduce available cargo space on the vehicle and be more dangerous to handle.

[0030] Optionally, the reformer comprises an outlet for discharging hydrogen which is — fluidically connectable or connected to a hydrogen inlet of the fuel cell.

[0031] Optionally, the reformer is configured to receive fuel via the fuel inlet and water via a water inlet, and in use generate hydrogen and carbon dioxide from the fuel. For example, the reformer produces at least hydrogen and carbon dioxide by reacting a fuel (such as methanol) and water (typically in the form of steam). Typically, the reacting the methanol and water is conducted in the presence of a catalyst.

[0032] Optionally, the reformer comprises a carbon dioxide outlet for discharging carbon dioxide. Optionally, the carbon dioxide outlet of the reformer is the carbon dioxide outlet of the electricity generation system. For example, the reformer is fluidically connectable or connected to the carbon dioxide inlet of the carbon dioxide capture system.

[0033] Optionally, the hydrogen outlet of the reformer is a hydrogen and carbon dioxide outlet for discharging hydrogen and carbon dioxide, and the hydrogen inlet of the fuel cell is a hydrogen and carbon dioxide inlet for receiving hydrogen and carbon dioxide from the reformer. For example, substantially all of the hydrogen and carbon dioxide generated by the reformer is provided by the reformer to the fuel cell. In examples, providing carbon dioxide to the fuel cell does not substantially reduce the efficiency of the fuel cell in generating electricity from the hydrogen. Optionally, the hydrogen and carbon dioxide outlet of the reformer is the only outlet of the reformer. Discharging all of the fluid generated by the reformer to the fuel cell advantageously simplifies the construction of the apparatus.

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[0034] The apparatus comprises the carbon dioxide capture system for receiving and storing the carbon dioxide. Optionally, the carbon dioxide outlet of the electricity generation system is for discharging gaseous carbon dioxide generated by the electricity generation system; and the carbon dioxide capture system comprises: a carbon dioxide condenser for condensing the gaseous carbon dioxide to liquid carbon dioxide, the carbon dioxide condenser comprising the carbon dioxide inlet of the carbon dioxide capture system and a carbon dioxide outlet for discharging the liquid carbon dioxide; and a container for containing the liquid carbon dioxide, the container having a carbon dioxide inlet fluidically connectable or connected to the carbon dioxide outlet of the carbon dioxide condenser.

[0035] The carbon dioxide condenser as described herein facilitates a phase change of gaseous carbon dioxide to liquid carbon dioxide according to any suitable method. The carbon dioxide condenser at least partly condenses the carbon dioxide by cooling the carbon dioxide using coolant received from the cooling system. Optionally, the carbon dioxide condenser condenses the gaseous carbon dioxide to liquid carbon dioxide by cooling and pressurising (e.g. compressing) the gaseous carbon dioxide to provide liquid carbon dioxide.

[0036] Optionally, the carbon dioxide capture system comprises a plurality of containers for containing liquid carbon dioxide. Each of the containers is fluidically connectable or connected to the carbon dioxide condenser. Optionally, one or more, or each, of the containers has a standard industrial size and shape. For example, one or more, or each, of the containers has the size and shape of an ISO container. Advantageously, carbon dioxide containers having the size and shape of ISO containers can more easily be offloaded from a vehicle (e.g. marine vessel) with standard offloading equipment.

[0037] Optionally, the carbon dioxide outlet of the electricity generation system is for discharging gaseous carbon dioxide generated by the electricity generation system; and the carbon dioxide capture system comprises a condensation and container unit. For example, the condenser and the container are the same unit. In use, the gaseous carbon dioxide is supplied to the module, the carbon dioxide is cooled and optionally pressurised inthe module such that the carbon dioxide condenses to its liquid phase, and is retained in the module under pressure. Optionally, the module comprises an outlet, typically in selectable fluid communication with the atmosphere external to the module via a valve,

DK 181364 B9 10 through which gaseous components can be discharged (e.g. components other than the carbon dioxide to be retained in the module, such as water, oxygen, or hydrogen) to reduce the amount of components other than carbon dioxide present in the module.

[0038] The container for containing the liquid carbon dioxide comprises at least one wall for retaining the liquid carbon dioxide within the container. Optionally, the container comprises an inner wall and an outer wall, the liquid carbon dioxide retained by the inner wall, such that the liquid carbon dioxide is separated from the external environment by the inner and outer walls. Separating the liquid carbon dioxide from the external environment by at least two walls advantageously reduces the likelihood of liquid carbon dioxide leaking from the container into the external environment if, for example, the outer wall of the container is breached (the carbon dioxide being retained by the inner wall).

[0039] The apparatus comprises a cooling system having a waste fluid inlet fluidically connectable or connected to the waste fluid outlet, wherein the cooling system is configured to use thermal energy from the waste fluid to cool coolant to be supplied to the carbon dioxide capture system for use in cooling the carbon dioxide in the carbon dioxide capture system.

[0040] Optionally, the cooling system comprises a heat exchanger and/or an absorption chiller. Advantageously, waste thermal energy generated by the electricity generation system during the electrochemical generation of electricity is transferred to the cooling system via the waste fluid and used by the heat exchanger and/or the absorption chiller to cool coolant (e.g. reduce the thermal energy of a fluid) to be supplied to the carbon dioxide capture system for cooling carbon dioxide, thereby reducing the energy requirements of the apparatus.

[0041] Optionally, the cooling system comprises a heat exchanger and an absorption chiller. Optionally, the heat exchanger comprises a waste fluid inlet for receiving waste fluid. Optionally, the waste fluid inlet of the heat exchanger is the waste fluid inlet of the cooling system. Optionally, the absorption chiller comprises a coolant outlet. Optionally, the coolant outlet of the absorption chiller is a coolant outlet of the cooling system which is fluidically connectable of connected to a coolant inlet of the carbon dioxide capture system.

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[0042] Optionally, the carbon dioxide capture system comprises a carbon dioxide condenser, and the cooling system is configured to supply the coolant to the carbon dioxide condenser.

[0043] Optionally, the waste fluid comprises water; the cooling system comprises a waste water outlet for discharging waste water; and the apparatus further comprises a condenser for condensing water vapour into liquid water. The condenser comprises a waste water inlet for receiving the waste water, the water inlet fluidically connectable or connected to the waste water outlet of the cooling system, and a water outlet for discharging the liquid water, the water outlet fluidically connectable or connected to a — water inlet of the electricity generation system for receiving the liquid water.

[0044] Optionally, the electricity generation system comprises a reformer and a fuel cell, and the water inlet of the electricity generation system is a water inlet of the reformer.

Advantageously, the reformer is configured to use the recycled water received from the condenser and fuel received via the fuel inlet to generate hydrogen for supplying to the fuel cell.

[0045] In some circumstances, e.g. where the vehicle is a marine vessel, water suitable for use by a reformer is scarce. Although suitable water can be generated onboard a marine vessel from seawater by, for example, reverse osmosis, such generation processes are energy-intensive and time-consuming, and therefore expensive to operate. Recycling waste water generated by the fuel cell for use in the reformer as described hereinabove therefore reduces the amount of water needed to be generated from seawater for use by the reformer.

[0046] Optionally, in any of the examples described hereinabove, the flow of fluid between an inlet and an outlet is controlled with one or more valves and/or pumps arranged between the inlet and the outlet.

[0047] A second aspect of the present invention provides a method for generating electricity for supplying to a device of a vehicle. The method comprises electrochemically generating the electricity with an electricity generator of an electricity generation system using a fuel, supplying carbon dioxide generated by the electricity generation system to acarbon dioxide capture system, cooling coolant using thermal energy from a waste fluid

DK 181364 B9 12 from the electricity generation system to create cooled coolant, using the cooled coolant at the carbon dioxide capture system to cool the carbon dioxide, and storing the carbon dioxide in the carbon dioxide capture system.

[0048] Optionally, the method comprises receiving a fluid comprising oxygen and optionally carbon dioxide at the electricity generation system for use by the electricity generator to generate the electricity, wherein the waste fluid is substantially free of carbon dioxide, or comprises carbon dioxide in a concentration less than or equal to a carbon dioxide content of the fluid received at the electricity generation system. For example, the fluid comprising oxygen and optionally carbon dioxide is atmospheric air.

[0049] Optionally, the fuel comprises one or more hydrocarbons, optionally one or more aliphatic hydrocarbons. Optionally, the fuel comprises methanol, ethanol, dimethyl ether, methane, or a combination thereof.

[0050] Optionally, the method is performed using an apparatus as described hereinabove.

[0051] A third aspect of the present invention provides a vehicle comprising the apparatus as described according to the first aspect. The vehicle is, for example, a marine vessel (e.g. a cargo ship, a container ship, a tanker, or a passenger ship) or a land vehicle (e.g. a truck, or a train).

[0052] Optionally, the vehicle is a marine vessel. Optionally, the marine vessel is a container ship.

[0053] Optionally, the marine vessel is a double-hull marine vessel, and at least part of the carbon dioxide capture system of the apparatus is arranged between an outer hull and an inner hull of the double-hull marine vessel.

[0054] Optionally, the marine vessel comprises the apparatus according to above- described examples wherein the carbon dioxide capture system comprises one or more containers for containing the liquid carbon dioxide. Optionally, at least one of the containers for containing liquid carbon dioxide is arranged between the outer hull and

DK 181364 B9 13 inner hull of the double-hull marine vessel. As noted above, it is advantageous for container to have an inner wall and an outer wall for reducing the likelihood of carbon dioxide leaks to the external environment. However, in examples wherein the container is arranged between the outer hull and the inner hull of the double-hull marine vessel, the need for the container itself to have an inner wall and outer wall is obviated, and therefore in examples the container comprises only one layer separating the carbon dioxide from the environment surrounding the container. In these examples, the inner hull and the outer hull of the marine vessel perform the function of an outer wall; the liquid carbon dioxide is separated from the environment external to the marine vessel by — a first layer (the wall of the container) and a second layer (the inner hull and outer hull of the marine vessel). Advantageously, containers having single walls are more readily available and/or less expensive to manufacture. Further, arranging one or more containers between the outer and inner hull makes use of space which is typically not utilised in the vessel, meaning that more space is available in the main body of the vessel for storing cargo.

[0055] Features described herein in relation to one aspect of the present disclosure are explicitly disclosed in combination with the other aspects, to the extent that they are compatible.

[0056] Further features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0058] Figure 1 shows a schematic apparatus for supplying electricity to a device of a vehicle according to examples;

[0059] Figure 2 shows a schematic apparatus for supplying electricity to a device of a vehicle according to examples;

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[0060] Figure 3 shows a schematic fuel cell according to examples;

[0061] Figure 4 shows a schematic absorption chiller according to examples;

[0062] Figure 5 shows a schematic flow chart of a method according to examples; and

[0063] Figure 6 shows a schematic marine vessel according to examples.

DETAILED DESCRIPTION

[0064] Figure 1 shows an example apparatus 100. The apparatus 100 comprises an electricity generation system 102, a carbon dioxide capture system 104, and a cooling system 106.

[0065] The electricity generation system 102 comprises a fuel inlet 108 for receiving fuel via a fuel conduit 110. Typically, the fuel conduit 110 fluidically connects the fuel inlet 108 with a fuel tank (not shown), such that fuel can be delivered to the electricity generation system 102 from the fuel tank via the fuel conduit 110 and the fuel inlet 108. Optionally, a pump, valve, or the like (not shown) is arranged between the fuel tank and the fuel inlet 108 to control the flow of fuel from the fuel tank to the electricity generation system 102.

Pumps, valves, or the like as referred to herein control the flow of fluid between parts of the apparatus by, for example, fluidically isolating parts of the apparatus from each other, restricting the flow of fluid between the parts of the apparatus, or pumping fluid on part of the apparatus to another.

[0066] The electricity generation system 102 further comprises an electricity generator 112 for electrochemically generating electricity using the fuel.

[0067] The electricity generation system 102 further comprises an electrical outlet 114 for supplying the electricity to a device of the vehicle (not shown). The electrical outlet 114 is typically connected to the device via an electrical conduit 116, indicated in dashed lines in Figure 1.

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[0068] The electricity generation system 102 further comprises a carbon dioxide outlet 118 for discharging carbon dioxide generated by the electricity generation system 102.

The carbon dioxide outlet 118 is typically a carbon dioxide exhaust.

[0069] The carbon dioxide capture system 104 comprises a carbon dioxide inlet 120 which is fluidically connectable or connected to the carbon dioxide outlet 118 of the electricity generation system 102. In this example, the carbon dioxide outlet 118 and the carbon dioxide inlet 120 are fluidically connected via a carbon dioxide conduit 122, thereby fluidically connecting the electricity generation system 102 and the carbon dioxide capture system 104. Optionally, a pump, valve, or the like (not shown) is arranged between the carbon dioxide outlet 118 and the carbon dioxide inlet 122 to control the flow of fluid from the electricity generation system 102 to the carbon capture system 104 along the carbon dioxide conduit 122.

[0070] The fluid which flows from the electricity generation system 102 is a carbon dioxide stream; the carbon dioxide stream comprises carbon dioxide. The carbon dioxide stream optionally comprises further components, such as unused fuel. The carbon dioxide stream has a high carbon dioxide content.

[0071] The electricity generation system 102 further comprises a waste fluid outlet 124 for discharging waste fluid from the electricity generation system 102. The waste fluid outlet 124 is typically a waste fluid exhaust.

[0072] The waste fluid which flows from the electricity generation system 102 to the cooling system 106 is a waste fluid stream. In this example, the waste fluid stream comprises water and optionally one or more of oxygen, nitrogen, and carbon dioxide.

The waste fluid stream has a carbon dioxide content less than the carbon dioxide content of the carbon dioxide stream.

[0073] The cooling system 106 comprises a waste fluid inlet 126 which is fluidically connectable or connected to the waste fluid outlet 124 of the electricity generation system 102. In this example, the waste fluid outlet 124 and the waste fluid inlet 126 are fluidically connected via a waste fluid conduit 128, thereby fluidically connecting the electricity generation system 102 and the cooling system 106. Optionally, a pump, valve, or the like (not shown) is arranged between the waste fluid outlet 124 and the waste fluid

DK 181364 B9 16 inlet 126 to control the flow of waste fluid from the electricity generation system 102 to the cooling system 106 along the waste fluid conduit 128.

[0074] The cooling system 106 comprises a coolant outlet 130. The carbon dioxide capture system 102 comprises a coolant inlet 132. The coolant outlet 130 of the cooling system 106 is fluidically connected to the coolant inlet 132 via a coolant conduit 134, thereby fluidically connecting the cooling system 106 and the carbon dioxide capture system. The apparatus is therefore configured such that the cooling system 106 can supply coolant to the carbon dioxide capture system 102.

[0075] Turning now to Figure 2, shown is a further example apparatus 200. At its broadest, the apparatus 200 includes the features of the example depicted in Figure 1.

Reference numerals of Figure 1 are included in Figure 2 to indicate corresponding features, where relevant, to aid understanding.

[0076] The apparatus 200 comprises the electricity generation system 102. In this example, the electricity generation system 102 comprises a reformer 202 and a fuel cell 204. The reformer 202 has a fuel inlet 206 for receiving fuel. The fuel inlet 206 is fluidically connected to a fuel outlet 208 of a fuel tank 210 via a fuel conduit 212.

[0077] In use, the reformer 202 generates hydrogen and carbon dioxide from the fuel received from fuel tank 210 and water. For example, the reformer produces hydrogen and carbon dioxide by reacting methanol and water (typically in the form of steam).

Typically, the reacting the methanol and water is conducted in the presence of a catalyst.

The reformer 202 comprises a hydrogen and carbon dioxide outlet 214 which is fluidically connected to a hydrogen and carbon dioxide inlet 216 of the fuel cell 204 via a hydrogen and carbon dioxide conduit 218. The reformer 202 further comprises a water inlet 220 for receiving water. In other examples (not shown), the hydrogen and carbon dioxide discharged from the reformer 202 is separated into a hydrogen stream and a carbon dioxide stream before the hydrogen is provided to the fuel cell 204. In these examples, the hydrogen stream is provided to the fuel cell 204 via the hydrogen conduit 218, and the carbon dioxide stream is provided to the carbon dioxide storage system 104 via another conduit (not shown) such that carbon dioxide generated by the reformer is not supplied to the fuel cell 204.

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[0078] In this example, the fuel cell 204 is a proton-exchange membrane fuel cell. An example of a suitable proton-exchange membrane fuel cell is illustrated in Figure 3, described hereinbelow. The fuel cell 204 comprises a hydrogen and carbon dioxide inlet 216 for receiving hydrogen and carbon dioxide and, on the same side as the hydrogen and carbon dioxide inlet 216, a carbon dioxide outlet 224 for discharging carbon dioxide.

[0079] The fuel cell 204 further comprises, opposed to the hydrogen and carbon dioxide inlet 216 and the carbon dioxide outlet 224, an oxygen inlet 226 for receiving oxygen, and a waste water outlet 228 for discharging waste water. In this example, the oxygen inlet 226 is an air inlet for receiving air from the atmosphere external to the fuel cell 204.

In other examples (not shown), the oxygen inlet 226 is an oxygen inlet for receiving substantially pure oxygen from an oxygen source, e.g. in use, substantially pure oxygen is supplied to the fuel cell 204 via the oxygen inlet 226. In examples, the oxygen source is an oxygen container for containing oxygen. In examples, the oxygen container is the carbon dioxide container — before use, the carbon dioxide container is charged with oxygen (and is thus an oxygen container). During use, oxygen is depleted from the carbon dioxide container as it is supplied to, and used by, the fuel cell 204, and carbon dioxide generated by the electricity generation system is supplied to the container. In examples, the carbon dioxide container includes a separator (e.g. a membrane) for separating oxygen and carbon dioxide which is contemporaneously contained in the carbon dioxide container.

[0080] In the example depicted in Figure 2, air is provided to the oxygen inlet 226 via an air conduit 230. In other examples (not shown), atmospheric air (e.g. air which is external to the fuel cell 204) enters the fuel cell 204 via the air inlet 226 in the absence of an air conduit 230.

[0081] The waste water outlet 228 is an outlet for discharging waste fluid. In this example, the waste fluid comprises waste water. The waste fluid stream discharged from the fuel cell 204 typically comprises other fluid components (e.g. nitrogen, carbon dioxide, and/or oxygen deriving from the air received at the fuel cell 204 via the air inlet 226 and air conduit 230). The waste fluid stream discharged from the fuel cell 204 via the waste water outlet 228 has a carbon dioxide content less than the carbon dioxide content of the carbon dioxide stream discharged from the carbon dioxide outlet 224.

Typically, the waste fluid steam has a carbon dioxide concentration less than or equal to

DK 181364 B9 18 the carbon dioxide concentration of the air received at the fuel cell 204 via the air inlet 226 and air conduit. For convenience, the waste fluid stream in this example will be simply referred as waste water, given that the waste fluid stream comprises waste water.

[0082] The fuel cell 204 further comprises an electrical outlet 232. The electrical outlet 232 is electrically connected to a device of the vehicle (not shown) via an electrical conduit 233. In this example, the device to which the electrical outlet 232 is electrically connected is a battery for storing electrochemical energy.

[0083] The apparatus 200 comprises the carbon dioxide capture system 104. In this example, the carbon capture system 104 comprises a carbon dioxide condenser 234 and a carbon dioxide storage tank 236 for storing carbon dioxide.

[0084] The carbon dioxide condenser 234 comprises a carbon dioxide inlet 238 for receiving carbon dioxide. The carbon dioxide inlet 238 is fluidically connected to the carbon dioxide outlet 224 of the fuel cell 204 via a carbon dioxide conduit 240. In this example, the carbon dioxide condenser 234 comprises a compression unit and a cooling unit (not shown). The cooling unit is in fluid communication with the cooling system 106, described further hereinbelow.

[0085] The carbon dioxide condenser 234 further comprises a liquid carbon dioxide outlet 242 for discharging liquid carbon dioxide. The liquid carbon dioxide outlet 242 is fluidically connected to a liquid carbon dioxide inlet 244 of the carbon dioxide storage tank 236 via a liquid carbon dioxide conduit 246.

[0086] The carbon dioxide storage tank 236 is a container having the size and shape of an ISO container. Optionally, the carbon dioxide storage tank 236 is arranged between the outer and inner hull of a double-hull marine vessel (not shown).

[0087] The apparatus 200 comprises the cooling system 106. In this example the cooling system 106 comprises a heat exchanger 248 and an absorption chiller 250.

DK 181364 B9 19

[0088] The heat exchanger 248 comprises a waste water inlet 252 for receiving waste water from the waste water outlet 228 of the fuel cell 204. The waste water outlet 228 is fluidically connected to the waste water inlet 252 via a first waste water conduit 254.

[0089] In use, the heat exchanger 248 transfers thermal energy from the waste water received at the waste water inlet 252 to a heat-conducting fluid. In this example, the heat- conducting fluid is water. The heat-conducting fluid is fluidically isolated from the waste water stream received at the waste water inlet 252; the heat-conducting fluid is circulated around a closed-loop system separate from the waste water stream.

[0090] The heat exchanger 248 comprises a heat-conducting-fluid outlet 256 for discharging heat-conducting fluid, the fluid having received thermal energy from the waste water stream received at the waste water inlet 252 via the heat exchanger 248.

The heat-conducting-fluid outlet 256 of the heat exchanger 248 is fluidically connected to a heat-conducting-fluid inlet 258 of the absorption chiller 250 via a first heat- conducting-fluid conduit 260.

[0091] The absorption chiller 250 transfer thermal energy from the heat-conducting fluid received at the heat-conducting-fluid inlet 258 to other components of the absorption chiller 250, described hereinbelow with respect to Figure 4.

[0092] The absorption chiller 250 further comprises a heat-conducting-fluid outlet 262 for discharging heat-conducting fluid which has been at least partially depleted of thermal energy by the absorption chiller 250; the heat-conducting fluid which is discharged from the heat-conducting-fluid outlet 262 is typically of a lower temperature than the heat- conducting fluid which is received at the heat-conducting-fluid inlet 258 of the absorption chiller 250.

[0093] The heat-conducting-fluid outlet 262 of the absorption chiller 250 is fluidically connected to a heat-conducting-fluid inlet 264 of the heat exchanger 248 via a second heat-conducting-fluid conduit 266. The heat-conducting fluid received at the heat- conducting-fluid inlet 264 of the heat exchanger 248 is typically of lower temperature than the heat-conducting fluid discharged from the heat-conducting-fluid outlet 256 of the heat exchanger 248.

DK 181364 B9 20

[0094] The heat-conducting fluid received at the heat-conducting-fluid inlet 264 of the heat exchanger 248 is heated by the heat exchanger, and discharged again via the heat- conducting-fluid fluid outlet 256.

[0095] Together, the heat-conducting-fluid outlet 256 of the heat exchanger 248, the first — heat-conducting-fluid conduit 260, the heat-conducting-fluid inlet 258 of the absorption chiller 250, the absorption chiller 250, the heat-conducting-fluid outlet 262 of the absorption chiller 250, the second heat-conducting-fluid conduit 266, the heat- conducting-fluid inlet 264 of the heat exchanger 248, and the heat exchanger 248 form a closed-loop system around which the heat-conducting fluid circulates during use, transferring thermal energy from the heat exchanger 248 to the absorption chiller 250.

Each of these features is in fluid communication with the other features.

[0096] The heat exchanger 248 further comprises a waste water outlet 268 for discharging waste water from the heat exchanger 248. The waste water outlet 268 is fluidically connected to the waste water inlet 252 of the heat exchanger 248; the waste water discharged from the waste water outlet 268 corresponds to the waste water received at the waste water inlet 252, the waste water having been at least partially depleted of thermal energy.

[0097] In use, the absorption chiller 250 cools coolant which is supplied to the carbon dioxide condenser 234 around a closed-loop coolant system. The absorption chiller 250 uses the thermal energy received from the heat exchanger 248 to cool the coolant; the carbon dioxide condenser 234 transfers thermal energy from the carbon dioxide in the carbon dioxide condenser 234 to the coolant received from the heat exchanger 248, thereby cooling and condensing the carbon dioxide to liquid carbon dioxide.

[0098] The absorption chiller 250 comprises a coolant outlet 270 for discharging cooled coolant. The coolant outlet 270 of the absorption chiller 250 is fluidically connected to a coolant inlet 272 of the carbon dioxide condenser 234 via a first coolant conduit 274.

[0099] The carbon dioxide condenser 234 transfers thermal energy from the carbon dioxide at the carbon dioxide condenser to the coolant received at the coolant inlet 272, thereby cooling the carbon dioxide and heating the coolant.

DK 181364 B9 21

[0100] The carbon dioxide condenser 234 further comprises a coolant outlet 276 for discharging coolant which has been heated (e.g. thermal energy has been transferred to the coolant) by the carbon dioxide condenser 234 in cooling the carbon dioxide; the coolant which is discharged from the coolant outlet 276 is typically of a higher temperature than the coolant which is received at the coolant inlet 272 of the carbon dioxide condenser 234.

[0101] The coolant outlet 276 of the carbon dioxide condenser 234 is fluidically connected to a coolant inlet 278 of the absorption chiller 250 via a second coolant conduit 280. The coolant received at the coolant inlet 278 of the absorption chiller 250 is typically — of a higher temperature than the coolant discharged from the coolant outlet 270 of the absorption chiller 250.

[0102] The coolant received at the coolant inlet 278 of the absorption chiller 250 is cooled by the absorption chiller 250 (e.g. the received coolant is at least partially depleted of thermal energy by the absorption chiller 250; thermal energy is transferred from the received coolant to the absorption chiller), and discharged again via the coolant outlet 270.

[0103] Together, the coolant outlet of the absorption chiller 250, the first coolant conduit 274, the coolant inlet 272 of the carbon dioxide condenser 234, the carbon dioxide condenser 234, coolant outlet 276 of the carbon dioxide condenser 234, the second coolant conduit 280, the coolant inlet 278 of the absorption chiller 250, and the absorption chiller 250 form a closed-loop system around which the coolant circulates during use, transferring thermal energy from the carbon dioxide condenser 234 to the absorption chiller 250. Each of these features is in fluid communication with the other features.

[0104] As described above, the heat exchanger 248 comprises a waste water outlet 268 for discharging waste water from the heat exchanger 248. The waste water outlet 268 is fluidically connected to a waste water inlet 282 of a water condenser 284 via a second waste water conduit 286. The water condenser 284 received water from heat exchanger at the waste water inlet 282.

[0105] Typically, the water received at the waste water inlet 282 is part of a waste fluid stream comprising water vapour (steam) and, optionally, other fluid components. The

DK 181364 B9 22 water condenser 284 condenses the water vapour received from the heat exchanger 248 to provide liquid water and, optionally, an exhaust stream comprising the other fluid components of the waste fluid stream received that the waste water inlet 282. The condensed liquid water is suitable for use by the reformer 202 in generating hydrogen and carbon dioxide from fuel and water. Water suitable for use by the reformer in generating hydrogen and carbon dioxide can be referred to as fresh water.

[0106] The condenser 284 comprises an exhaust outlet 286 for discharging the exhaust stream from the condenser 284. In this example, the exhaust stream is discharged into the environment external to the condenser 284 via the exhaust outlet 286 and an exhaust conduit 288 fluidically connected to the exhaust outlet. In other examples (not shown), the exhaust stream is discharged into the environment external to the condenser 284 directly from the exhaust outlet 286; an exhaust conduit 288 is not present.

[0107] Typically, the exhaust stream has a carbon dioxide content equal to or less than the carbon dioxide content of the atmospheric air external to the apparatus 200. For example, the exhaust stream has a carbon dioxide content equal to or less than the air received at the fuel cell 204 via the air inlet 226 and air conduit 230.

[0108] The condenser 284 comprises a fresh water outlet 290 for discharging fresh water from the condenser 284. The fresh water outlet 290 is fluidically connected to the water inlet 220 of the reformer 202 via a fresh water conduit 292. The apparatus 200 is configured that, in use, the reformer 202 receives fresh water from the condenser 284.

The fresh water is recycled water — water which has been generated by the fuel cell 204 has been recycled for use as fresh water in the reformer 202.

[0109] In other examples (not shown), the apparatus receives fresh water at the water inlet 220 of the reformer 202 from a reverse osmosis system, the reverse osmosis system having generated fresh water from seawater.

[0110] Features of Figure 2 have been described as being in fluid communication with each other. In this example, features are either in direct fluid communication, or indirect fluid communication. For example, the flow of fluid between one or more features in fluid communication is controlled by one or more pumps, valves, restrictions, and the like

DK 181364 B9 23 between the one or more features (e.g. one or more pumps, valves, restrictions, and the like is arranged along a conduit connecting an inlet and an outlet).

[0111] Turning now to Figure 3, shown is an example fuel cell 300. The fuel cell 300 depicted in Figure 3 is a proton-exchange membrane fuel cell which corresponds to the fuel cell 204 depicted in Figure 2 as part of the apparatus 200.

[0112] The fuel cell 300 comprises an anode 302, a cathode 304, and, sandwiched between the anode 302 and cathode 304, an electrolyte 306. In this example, the electrolyte 306 is a solid electrolyte.

[0113] At the anode 302 side of the fuel cell 300, the fuel cell 300 comprises a hydrogen inlet 308 for receiving hydrogen at the anode 302. In this example, in use, hydrogen is received at the anode 302 from a reformer via the hydrogen inlet 308. The reformer generates hydrogen and carbon dioxide by reacting a fuel (e.g. methanol) with water.

Thus the hydrogen inlet 308 is a hydrogen and carbon dioxide inlet 308, because the anode 302 receives both hydrogen and carbon dioxide from the reformer. The hydrogen and carbon dioxide inlet 308 corresponds to the inlet 216 depicted in Figure 2.

[0114] The fuel cell 300 further comprises, at the anode 302 side of the fuel cell 300, a carbon dioxide outlet 310, or fuel cell exhaust 310. The fuel cell exhaust 310 is for discharging material from the anode 302 side of the fuel cell 302. The material discharged from the fuel cell 300 via the carbon dioxide outlet 310 comprises carbon dioxide and any residual hydrogen which has not been used by the fuel cell 300. The carbon dioxide outlet 310 corresponds to the outlet 224 depicted in Figure 2.

[0115] The hydrogen and carbon dioxide inlet 308 and carbon dioxide outlet 310 are fluidically connected by a conduit 312, along which at least some of the material received via the inlet 308 is in contact with the anode 302. In use, hydrogen provided to the anode 302 is separated into protons and electrons. The protons travel to the cathode 304 via the electrolyte 306.

[0116] At the cathode 304 side of the fuel cell 300, the fuel cell 300 comprises an oxidant inlet 314 for receiving oxidant. In this example, the oxidant is oxygen. The oxygen may be provided as part of a fluid stream comprising other components. In this example, the

DK 181364 B9 24 oxygen is provided as part of an atmospheric air stream; the oxygen used by the fuel cell 300 in generating electricity is oxygen present in atmospheric air. The oxidant inlet 314 corresponds to the inlet 226 depicted in Figure 2.

[0117] The fuel cell 300 further comprises, at the cathode 304 side of the fuel cell 300, a waste fluid outlet 316. In this example, the waste fluid comprises water, such that the waste fluid outlet is a waste water outlet 316.

[0118] The oxidant inlet 314 and waste fluid outlet 316 are fluidically connected by a conduit 318, along which at least some of the material received via the inlet 314 is in contact with the cathode 304. In use, oxygen provided to the cathode 304 is consumed, and water is generated. The generated water is not used by the fuel cell in generating electricity, and thus is termed waste water. The waste water is discharged from the fuel cell 300 via the waste water outlet 316.

[0119] As described hereinabove, in use, hydrogen provided to the anode 302 is separated into protons and electrons. The electrons are conducted from the anode 302 to a device 320 of the vehicle (not shown) via an electrical outlet 322 and a first electrical conduit 324, and electrons are conducted from the device 320 to the cathode 304 via a second electrical conduit 326 and an electrical inlet 328.

[0120] Turning now to Figure 4, shown is an example absorption chiller 400. The absorption chiller 400 depicted in Figure 4 corresponds to the absorption chiller 250 depicted in Figure 2 as part of the apparatus 200.

[0121] The absorption chiller 400 comprises a first tank 402 and a second tank 404. The first tank 402 has a first portion 402a and a second portion 402b; the second tank has a first portion 404a and a second portion 404b.

[0122] The absorption chiller further comprises a heated-fluid loop 406, a coolant loop 408, a condensate conduit 410, a secondary coolant loop 412, and a salt solution loop 414.

DK 181364 B9 25

[0123] The heated-fluid loop 406 comprises a heated-fluid inlet 416 and a heated-fluid outlet 418 fluidically connected by a heated-fluid conduit 420. The heated-fluid inlet 416 and heated-fluid outlet 418 correspond to the inlet 258 and outlet 262 depicted in Figure 4, respectively. The heated-fluid conduit 420 comprises at least one thermally-conductive wall, such that thermal energy can be transferred from the heated fluid received at the heated-fluid inlet 416 to the environment external to the heated-fluid conduit 420.

[0124] The heated-fluid conduit 410 passes through the first portion 402a of the first tank 402 such that the thermally-conductive wall of the heated-fluid conduit 420 is in thermal communication with the interior of the first tank 402, in particular the interior of the first portion 402a of the tank 402. In use, thermal energy is transferred from the heated fluid received at the heated-fluid inlet 416 to the interior of the first tank 402. The first portion 402a of the first tank may be referred to as a generator.

[0125] In use, a high-concentration aqueous salt solution 422 is provided in the first portion 402a of the first tank 418. The salt is a deliquescent salt. In this example, the — deliquescent salt is lithium bromide (LiBr); in use a high-concentration aqueous lithium bromide solution 422 is provided in the first portion 402a of the first tank 402 in use.

[0126] In use, the thermal energy transferred to the interior of the first tank 402 causes at least some of the water of the high-concentration aqueous lithium bromide solution 422 to evaporate, thereby providing water vapour and a further-concentration aqueous lithium bromide solution.

[0127] The generated water vapour passes from the first portion 402a of the first tank 402 to a second portion 402b of the first tank 402. In the second portion 402b of the first tank 402, energy is transferred from the water vapour to cooling fluid in a first portion 412a of the secondary coolant loop 412; the secondary coolant loop 412 cools at least some of the water vapour in the second portion 418b of the first tank 418 such that the water vapour condenses as liquid water 424, or condensate 424. The liquid water 424 has a lower lithium bromide concentration than the high-concentration lithium bromide solution 422; the liquid water 424 is substantially free of lithium bromide. The second portion 402b of the first tank 402 may be referred to as a condenser.

DK 181364 B9 26

[0128] The energy transferred to the cooling fluid from the water vapour in the second portion 402a of the first tank 402 corresponds to the energy associated with the change of temperature as well as the energy released upon changing from a less-ordered phase to a more-ordered phase (i.e. the phase change from water vapour to liquid water is exothermic).

[0129] The first portion 412a of the secondary coolant loop comprises at least one thermally-conductive wall in thermal communication with the interior of the first tank 402, such that thermal energy can pass from the vapour in the second portion 402a of the first tank 402 to the cooling fluid in the secondary coolant loop 412. In this example, the — cooling fluid in the secondary coolant loop is water.

[0130] The cooling fluid in the first portion 412a of the secondary coolant loop 412 which has received energy from the water vapour in the first tank 402 leaves the first tank 402 and is transferred to a cooling tower which forms part of the secondary coolant loop 412 (not shown). The cooling fluid is cooled at the cooling tower and reintroduced to the system at the second portion 412b of the secondary coolant loop 412b.

[0131] The interior of the first tank 402 is typically under a pressure corresponding to atmospheric pressure.

[0132] The condensate 424 is transferred from the second portion 402b of the first tank 402 to a first portion 404a of the second tank 404 via the condensate conduit 410. The interior of the second tank 404 is under a reduced pressure compared with the first tank.

For example, the interior of the second tank 404 is under a pressure less than atmospheric pressure. In some examples, the interior of the second tank 404 is substantially under vacuum.

[0133] The coolant loop comprises a coolant inlet 426 and a coolant outlet 428 fluidically connected by a coolant conduit 430. The coolant inlet 426 and coolant outlet 428 correspond to the inlet 278 and outlet 270 depicted in Figure 2, respectively. Similar to the heated-fluid conduit 420, the coolant conduit 430 comprises at least one thermally- conductive wall, such that thermal energy can be transferred from coolant received at the coolant inlet 426 to the environment external to the coolant conduit 430.

DK 181364 B9 27

[0134] The coolant conduit 430 passes through the first portion 404a of the second tank 404 such that the thermally-conductive wall of the coolant conduit 430 is in thermal communication with the interior of the second tank 404, in particular the interior of the first portion 404a of the tank 404. In use, thermal energy is transferred from the coolant received at the coolant inlet 426 to the interior of the second tank 404. The first portion 404a of the second tank 404 may be referred to as an evaporator.

[0135] In use, the condensate 424 is delivered to the interior of the first portion 404a of the second tank 404 from the condensate conduit 410 and/or a condensate recirculation loop 432 via a spray head 434. Delivering the condensate 424 via a spray head 434 typically serves to disperse the condensate 424 in the first portion 404a of the second tank 404.

[0136] In use, thermal energy is transferred from the coolant received at the coolant inlet 426 to the condensate 424 which has been delivered to the first portion 404a of the second tank 404. The temperature at which water will change phase from liquid to gas — of water is lower at reduced pressure (e.g. the water has a reduced boiling point under reduced pressure). Therefore, because the interior of the second tank is under reduced pressure, the energy received from the coolant is sufficient to vaporise the condensate 424 (i.e. the water changes phase from liquid to gas). The energy transferred from the coolant to the water corresponds to the energy associated with the change of temperature of the water as well as the energy absorbed upon changing from a more- ordered phase to a less-ordered phase (i.e. the phase change from liquid water to water vapour is endothermic). Thus, the temperature of the coolant is reduced in the coolant conduit 430 (the coolant is cooled), and the cooled coolant is discharged from the heat absorber 400 via the coolant outlet 426 to the carbon dioxide condenser where it is used to cool and condense gaseous carbon dioxide to liquid carbon dioxide.

[0137] As mentioned above, the absorption chiller 400 comprises a water recirculation loop 432. The water recirculation loop comprises a pump 436 for pumping liquid water from the bottom of the second tank 404 to the top of the second tank 404 and delivering the liquid water to the first portion 404a of the second tank via the spray head, at least a part of which will then be evaporated through transfer of energy from the coolant conduit 430 to the water.

DK 181364 B9 28

[0138] At least a portion of water is transferred from the first portion 404a of the second tank 404 to the second portion 404b of the second tank. The second portion 404b of the second tank may be referred to as an absorber.

[0139] At least a portion of the high-concentration aqueous lithium bromide solution is supplied to second portion 404a of the second tank from the first portion 402a of the first tank 402a via the salt solution loop 414 comprising a first conduit 438, a first pump 440 for pumping salt solution from the first tank 402 to the second tank 404, and a first spray head 442 for dispersing the high-concentration aqueous lithium bromide solution in the second portion 404b of the second tank 404.

[0140] A second portion 412b of the secondary cooling loop 412 is arranged in the second portion 404b of the second tank 404. In use, energy is transferred from the water vapour to the cooling fluid in the secondary cooling loop. Further, the lithium bromide present in the second portion 404b of the second tank 404 is deliquescent. Both of these aspects contribute to condensing the liquid vapour in the second portion 404b of the second tank 404 to liquid water, where it collects along with the aqueous lithium bromide solution delivered to the second portion 404b, thereby providing a low-concentration aqueous lithium bromide solution 444.

[0141] The low-concentration aqueous lithium bromide solution 444 is provided to the first portion 402a of the first tank 402a via the salt solution loop 404 which further comprises a second conduit 446, a second pump 448 for pumping salt solution from the second tank 404 to the first tank 402, and a second spray head 450 for dispersing the low-concentration aqueous lithium bromide solution in the first portion 402a of the first tank 402. There, the low-concentration aqueous lithium bromide solution 444 is heated to provide water vapour and high-concentration aqueous lithium bromide solution 422 as described hereinabove, and the heating/cooling cycle continues.

[0142] The condensation and evaporation phase changes are further aided by the heat exchanger 452 which transfers thermal energy from the high-concentration lithium bromide solution 422 during its transfer to the second tank 404, to the low-concentration lithium bromide solution 444 during its transfer to the first tank 402. It is desirable that the high-concentration lithium bromide solution 422 loses thermal energy during its transfer to the second portion 404b of the second tank 404 so that a large proportion of

DK 181364 B9 29 the water in the solution remains as water even as it is delivered to the low pressure environment of the second tank 404. It is desirable that the low-concentration lithium bromide solution 444 receives thermal energy during its transfer to the first portion 402a of the first tank 402 to that a large proportion of the water in the solution is more readily evaporated in the high temperature, high pressure environment of the first tank 402.

[0143] Figure 4 and its associated description demonstrates how the cooling system (in particular the absorption chiller) uses thermal energy from waste fluid discharged from the electricity generation system to cool coolant for supply to the carbon dioxide capture system.

[0144] Turning now to Figure 5, shown is an example method 500. The method 500 is a method of generating electricity and storing carbon dioxide. In this example, the method 500 is performed using the apparatus 200 depicted in Figure 2.

[0145] The method 500 comprises electrochemically generating electricity 510. In this example, the electrochemically generating electricity 510 comprises supplying 512 fuel and water to a reformer, generating 514 hydrogen and carbon dioxide at the reformer, supplying 516 the hydrogen and carbon dioxide to the anode of a fuel cell, and supplying 518 oxygen to the cathode of a fuel cell, thereby generating electricity and a waste fluid (in this example, waste water).

[0146] The method 500 further comprises supplying 520 the carbon dioxide generated inthe electrochemical generation of electricity to a carbon dioxide capture system. In this example, the carbon dioxide capture system comprises a carbon dioxide condenser for receiving the generated carbon dioxide, and a container for storing liquid carbon dioxide received from the carbon dioxide condenser.

[0147] The method 500 further comprises cooling coolant using thermal energy from the waste fluid generated in the electrochemical generation of electricity 530. In this example, a heat exchanger of a cooling system receives 532 thermal energy from waste fluid discharged from the fuel cell, transfers 534 the thermal energy to an absorption chiller, and using the thermal energy received from the heat exchanger, the absorption cooler cools 536 the coolant.

DK 181364 B9 30

[0148] The method 500 further comprises using the cooled coolant to cool 540 the carbon dioxide in the carbon dioxide condenser. In this example, the using the cooled coolant 540 comprises supplying 542 cooled coolant to the carbon dioxide condenser from the absorption chiller, and transferring 544 thermal energy to the received coolant from the carbon dioxide in the carbon dioxide condenser, thereby cooling and condensing gaseous carbon dioxide in the condenser to liquid carbon dioxide.

[0149] The method 500 further comprises storing 550 the carbon dioxide. In this example, the storing 550 the carbon dioxide comprises supplying 552 liquid carbon dioxide from the carbon dioxide condenser to the container for storing liquid carbon dioxide, and storing 554 the liquid carbon dioxide in the container.

[0150] Turning now to Figure 6, shown is an example marine vessel 600. The marine vessel 600 comprises an apparatus corresponding to an example of the apparatus 100 depicted in Figure 1, wherein the carbon dioxide capture system 104 comprises a carbon dioxide condenser 234 and a first and second carbon dioxide container 236a, 236b. The components of the apparatus are fluidically connectable or connected as described hereinabove.

[0151] The marine vessel 600 is a double-hull vessel comprising a first, outer hull 602 and a second, inner hull 604. Typically the space between the outer hull 602 and inner hull is a chamber 606 devoid of cargo.

[0152] The first and second carbon dioxide containers 236a, 236b are arranged between the outer hull 602 and the inner hull 604; the containers 236a, 236b are arranged in the chamber at least partially defined by the outer hull 602 and inner hull 604. In this example, the containers 236a, 236b are single-wall containers (as opposed to double- wall containers), because the outer hull 602 and inner hull 604 provide a further barrier between the liquid carbon dioxide stored in the containers 236a, 236b and the environment external to the marine vessel 600.

[0153] In other embodiments, two or more of the above described embodiments may be combined. In other embodiments, features of one embodiment may be combined with features of one or more other embodiments.

DK 181364 B9 31

[0154] Example embodiments of the present invention have been discussed, with particular reference to the examples illustrated. However, it will be appreciated that variations and modifications may be made without departing from the scope of the invention as defined by the appended claims.

Claims

DK 181364 B9 32 Patent claim

1. Device (100, 200) for supplying electricity to a unit in a vessel, which — device (100, 200) comprises: an electricity generation system (102) comprising: a fuel inlet (108, 206) for receiving fuel, an electrical generator (112) for electrochemically generating electricity using the fuel, an electrical outlet (114, 232) for supplying electricity to the unit, a waste fluid outlet (124, 228) for discharging waste fluid from the electrical generation system (102) and a carbon dioxide outlet (118, 224) for discharging carbon dioxide generated by the power generation system (102), which carbon dioxide outlet (118, 224) is separate from the waste liquid outlet (124, 228); a carbon dioxide capture system (104) having a carbon dioxide inlet (120, 238) fluidly connectable or connected to the carbon dioxide outlet (118, 224), wherein the carbon dioxide capture system (104) is for receiving and storing the carbon dioxide; and a cooling system (106) having a waste fluid inlet (126, 252) fluidly connectable or connected to the waste fluid outlet (124, 228), wherein the cooling system (106) is configured to use thermal energy from the waste fluid to cool coolant to be supplied to the carbon dioxide capture system (104) for use in cooling the carbon dioxide in the carbon dioxide capture system (104).

2. Device (200) according to claim 1, wherein the electric generator (112) comprises a fuel cell (204).

3. Device (200) according to claim 2, wherein the electricity generation system (102) comprises a reformer (202) for receiving the fuel via the fuel inlet (206) and for generating hydrogen from the fuel, where the fuel cell (204) can be fluidly connected or connected with the reformer (202) and where the fuel cell (204) is

DK 181364 B9 33 for receiving hydrogen from the reformer (202) and generating the electricity using the hydrogen.

Device (200) according to any one of claims 1 to 3, wherein — the carbon dioxide outlet (118, 224) is for discharging gaseous carbon dioxide generated by the electricity generation system (102); and wherein the carbon dioxide capture system (104) comprises: a carbon dioxide condenser (234) for condensing the gaseous carbon dioxide to liquid carbon dioxide, said carbon dioxide condenser (234) comprising the carbon dioxide inlet (120, 238) to the carbon dioxide capture system (104) and a carbon dioxide outlet (242) for discharging the liquid carbon dioxide; and a container (236) for containing the liquid carbon dioxide, which container (236) has a carbon dioxide inlet (244) fluidly connectable or connected to the carbon dioxide outlet (242) from the carbon dioxide condenser (234).

5. Device (200) according to claim 4, wherein the cooling system (106) is configured to supply the coolant to the carbon dioxide condenser (234).

Device (200) according to any one of claims 1 to 5, wherein: the waste fluid comprises water; the cooling system (106) comprises a waste water outlet (268) for discharging waste water, and the device (200) further comprises a condenser (284) for condensing water vapor to liquid water, which condenser (284) comprises: a waste water inlet (282) for receiving the waste water, which water inlet (282) can be fluidly connected or connected to the cooling system (106) waste water outlet (268), and a water outlet (290) for discharging the liquid water, which water outlet (290) can be fluidly connected or connected to a water inlet (220 ) in the power generation system (102) for receiving the liquid water.

DK 181364 B9 34

7. Method (500) for generating electricity for supply to a device in a vessel (600), which method (500) comprises: electrochemically generating the electricity (510) with an electricity generator (112) in an electricity generation system (102) using of a fuel; supplying (520) carbon dioxide generated by the power generation system (102) to a carbon dioxide capture system (104); cooling refrigerant using thermal energy from a waste fluid from the power generation system (102) to produce cooled refrigerant (530); using the cooled refrigerant at the carbon dioxide capture system (104) to cool (540) the carbon dioxide and store (550) the carbon dioxide in the carbon dioxide capture system (104).

8. Method (500) according to claim 7, and which comprises receiving a liquid comprising oxygen and possibly carbon dioxide at the electricity generation system (102) for —= use for the electricity generator (112) to generate the electricity, where the waste liquid essentially is free of carbon dioxide or comprises carbon dioxide in a concentration less than or equal to a carbon dioxide content of the liquid received by the electricity generation system (102).

Vessel (600) comprising the device (100, 200) according to any one of claims 1 to 6.

10. — Vessel (600) according to claim 9, wherein the vessel (600) is a marine vessel.