DE102019133180A1 - Energy storage system for buildings - Google Patents

Abstract

The invention relates to a system in a building for converting and storing energy. The generated energy is converted into potential energy as well as thermal energy of the same medium and stored. The energy generated includes electrical energy and thermal energy. The system comprises an electrical energy source which is in particular a solar cell arrangement, an energy converter which is in particular a generator, a pump and / or a turbine, a thermal energy source which is in particular an arrangement of solar collectors; and a heat exchanger.

Description

The invention relates to a system in a building for converting and storing energy according to the preamble of claim 1.

State of the art

As the world's population grows and industrialization in developing countries accelerates, global energy demand continues to rise. At the same time, the rise in carbon emissions brings the threat of uncontrollable climate change and a drastic reduction in the earth's ability to support human life ever closer. Renewable energies are one of the most important human issues for our generation and all the more important for future generations.

An important branch of technology in energy supply are the so-called renewable energies, which generate electricity and heat energy _{as CO 2 -neutral as possible.} In contrast to centralized electricity production by conventional power plants, such as coal and nuclear power plants, in which the electricity network infrastructure from central locations of the power plants converges, decentralized electricity network solutions are required for renewable energies.

Another problem with renewable energies is the time of day and weather-dependent fluctuations in energy generation. While solar energy only generates electricity during the day, and especially at noon when the sky is not cloudy, electricity generation drops to zero at night. Wind energy is also not constantly available, but is linked to the weather.

In order to compensate for these fluctuations in energy production, it is necessary to provide energy storage devices. One way of storing energy, especially in private households with solar systems, is the use of large battery storage systems. A major disadvantage of these battery storage systems, however, is the high consumption of resources and environmental damage caused by the breakdown of valuable metals, such as lithium, which are required for such battery storage systems.

Another form of energy storage, mainly used on larger energy scales, is pumped storage power plants. Here, water is pumped to a certain height by electric pumps and thus the electrical energy is converted into height energy (potential energy) of the water. Later, the dammed water is used to drive a turbine and a generator to generate electrical energy again.

One problem with such a pumped storage power plant, however, is the high cost, since large reservoirs have to be created for this. The construction is tied to the landscape, causes further ecological damage, requires long planning and approval times and thus loses flexibility, which is very important in the field of renewable energy.

task

It is therefore the object of the invention to provide a system in a building for converting and storing energy.

solution

The object is achieved according to the invention by a system according to claim 1. Advantageous embodiments and developments are covered in the subclaims.

One embodiment of the invention relates to a system in a building for converting and storing energy, wherein the energy generated can be converted and stored both into potential energy and into thermal energy of the same medium. The energy generated can include electrical energy and thermal energy. The system can comprise an electrical energy source, which can in particular be a solar cell arrangement, and which is configured to generate and / or output the electrical energy.

Furthermore, the system can comprise an energy converter, which can in particular be a generator, a pump and / or a turbine, and which is configured to convert at least part of the electrical energy from the electrical energy source into the potential energy of a liquid, and convert it from stored potential energy of the liquid into electrical energy.

The system can further comprise a thermal energy source, which is in particular an arrangement of solar collectors, and which is configured to generate the thermal energy, the thermal energy being stored in the form of thermal energy of the liquid. The system can further comprise a heat exchanger which is configured to receive and / or release the thermal energy of the liquid in a controlled manner.

• 1 eine schematische Ansicht eines Systems in einem Gebäude zum Umwandeln und Speichern von Energie, gemäß einer Ausführungsform der Erfindung; und
• 2 eine schematische Ansicht eines Systems in einem Gebäude zum Umwandeln und Speichern von Energie und einen Wärmekreislauf eines Heizungssystems, gemäß einer Ausführungsform der Erfindung.

Embodiments according to the invention are described with reference to the following drawings. Show it:

• 1 a schematic view of a system in a building for converting and storing energy, according to an embodiment of the invention; and
• 2 a schematic view of a system in a building for converting and storing energy and a heat circuit of a heating system, according to an embodiment of the invention.

The invention relates to an energy storage concept which combines an energy-efficient construction for buildings with the advantages of a storage power plant, but without having to accept the enormous planning-related and ecological disadvantages of a pumped storage power plant.

1 shows a building with solar cells on its roof 101 and solar panels 102 are arranged. The arrangement of the solar cells shown in the figures 101 and solar panels 202 are only exemplary here and can also be done in a different way. For example, the solar panels 102 and the solar cells 101 can also be arranged next to the building, or can be arranged in a different relationship.

The solar cells 101 on the roof of the building produce electrical energy by a control system 104 is regulated and managed. Solar cells 101 convert sunlight (electromagnetic waves) into electrical energy and emit the electrical energy in the form of direct voltage.

The tax system 104 includes a power converter that takes the DC voltage from the solar cells 101 converted to AC voltage, such as 220 V, 60 Hz mains voltage. The AC voltage can then be supplied by the control system 104 to various consumers in the building via corresponding power connections 106a-d be transmitted.

In general, the tax system includes 104 all the usual technology and electronics necessary for the operation of solar cells 102 are needed.

According to one embodiment, the system comprises an upper basin 110 and a lower basin 111 that have a line 106 are connected to each other. As seen in the figures is the upper pelvis 110 Arranged as high up in the building as possible (for example directly below a roof), whereas the lower basin 111 is located at the lowest possible point in the building (for example in the basement or under the basement). The upper pelvis 110 and the lower pelvis 111 are designed to absorb a certain amount of water.

The administration 106 , which is the upper pelvis 110 and the lower pelvis 111 connects with each other is also with an energy converter 105 connected.

The energy converter 105 includes a pump that draws water from the lower basin 111 in the upper pelvis 110 can be pumped. The energy converter 105 is with the tax system 104 electrically connected, and thus uses that of the solar cells 101 generated electrical energy to get water from the lower basin 111 in the upper pelvis 110 to pump. This process generates electrical energy from the solar cells 101 converted into potential energy of the water.

For example, the building can have a floor plan of 15 × 15 m ² and both the lower basin 111 as well as the upper pelvis 110 each take up a volume of about 300 m ^{3 of} service water. The process water does not necessarily have to be tap water, but can, for example, be saturated salt water, which increases the density and thus the mass of the water by a factor of 1.4 compared to fresh water. This also increases the capacity of the storage system by a factor of 1.4. Assuming the difference in height between the lower pelvis 111 and the upper pelvis 110 is about 10m and according to the physical formula Epot = mxgxh (where g = 9.81 m / s ^{2 is} the gravitational acceleration constant) an energy of Epot = (300,000x1.4x9.81x10) J = 41.2 can be achieved with this exemplary system Save MJ = 11 kWh.

With an assumed area of 130 m ² solar cells, an average of 18.2 kWh / day can be generated in Germany. A comparison of these figures shows that the size given above as an example applies to the upper pelvis 110 , the lower pelvis 111 and the height of about 10 m represents an efficient and realistic storage system. The above figures are not intended to be limiting, however, and various dimensions can be used to store electrical energy in the form of potential energy from water.

When there is water in the upper basin 110 of the system is located, this can be done via the line 106 back to the lower pelvis 111 be drained. This causes the water to run through the energy converter 105 which, in addition to the pump, comprises a turbine that is driven by the water flowing down. The turbine in the energy converter 105 in turn drives a generator, which generates electrical energy, which is then fed through the control system 104 with the Power connections 106a-d can be consumed, or can be discharged to the outside in another form.

According to one embodiment, the pump and the turbine are in the energy converter 105 a single component. According to an alternative embodiment, for the pump and the turbine in the energy converter 105 separate components are used. The electronics of the energy converter 105 can also be powered by the solar cells 101 operate. In one embodiment, the energy converter comprises 105 Furthermore, a backup battery to protect the electronics, which can be particularly advantageous when the turbine is started by the water flowing down.

The power line shown in the figures with the power connections 106a-d is also still with an external power line 107 connected to receive electrical energy from an external power grid, and / or to receive electrical energy from the external power grid.

The building or the storage system in the building can also be used as part of a larger energy storage system in order to be used as storage for current peaks from solar energy generation, wind energy generation, gas power plants, or similar power plants and energy generation systems from external power plants.

With this architecture, an efficient and decentralized storage power plant can be created without environmental damage, reservoir formation or lengthy building permits. This is particularly advantageous in remote areas of the world in order to set up decentralized power grids between several buildings.

As in 1 Furthermore, it can be seen that the system includes in addition to the solar cells 101 an arrangement of solar panels on the roof of the building 102 . The solar panels 102 are a device for heating water. The solar panels 102 convert irradiated sunlight (thermal energy) into thermal energy from water. For the sake of simplicity, it is referred to herein as converting thermal energy (solar energy) into thermal energy of a medium (such as water).

As can be seen in the figures, the solar panels are 102 with an inlet 103a and a sequence 103b connected to water from the upper basin 110 take in, heat up and give back. Inside the solar panels 102 A pipe system runs through which the water is transported and is heated up by the thermal energy of the sun, so that the water absorbs the externally supplied thermal energy and stores it in the form of thermal energy.

The inflow 103a and expiration 103b do not necessarily have to be with the upper pelvis 110 be connected, but can also be connected to the line 106 or with the lower pelvis 111 be connected. Furthermore, the solar panels must 102 not necessarily be arranged on the roof of the building, but can, for example, also be arranged next to the building, or can for example be attached to the walls of the building.

With an assumed area of around 95 m ^{2 for} the solar collectors, 300 m ^{3 of} service water results in an approximate warming of 0.2 ° C of the water per day, averaged over the year. These from the solar panels 102 The thermal energy generated can thus be in the form of thermal energy of the water in the upper basin 110 and the lower pelvis 111 get saved.

With these exemplary figures, thermal energy of 9,500 kWh can be stored in 100 days in the form of thermal energy from the water. The demand of older houses is around 6,000 kWh per year.

Thus, the water in the upper basin 110 not only used for storage in the form of potential energy, but also used to store thermal energy in the form of thermal energy of the water. This can be included directly in the energy balance of the house, creating a system that generates more energy than it consumes.

In order to ensure a controlled release of the thermal energy of the water, both the upper basin 110 , as well as the lower pelvis 111 and the line 106 be equipped with thermal insulation so that the heated water can be released into the environment in an uncontrolled manner.

The heated water can then be used by means of one or more heat exchangers to release the thermal energy of the water in a controlled and targeted manner to the environment. For example, the water can be used for radiators to heat the rooms in the building.

As for example in 2 several heat exchangers can be seen 210a-d arranged in the different floors of the building. The heat exchangers 210a-d can be switched on or off individually.

In 2 are the heat exchangers 210a-d with the line 106 connected to which the upper pelvis 110 with the lower pelvis 111 connects. However, this is only an exemplary arrangement of the heat exchangers 210a-d . The heat exchangers 210a-d can also be connected to either or both of the upper basin via a separate conduit (not shown) 110 and the lower pelvis 111 be connected.

The system can also use heat exchangers, particularly in warmer regions of the world 210a-d use the spaces through the water (especially the water from the lower basin 111 ) to cool. In this case, take the heat exchanger 210a-d the heat from the rooms, and thus cool the rooms.

The heat exchangers 210a-d can be a heating system such as radiators or underfloor heating, or a combination of these. Furthermore, the heat exchangers 210a-d also comprise a device for heating tap water.

While the system can be integrated relatively easily into the planning for new buildings, retrofitting for existing buildings is in principle possible, but requires significantly more effort, since additional space for the upper water basin is required 110 and the lower water basin 111 must be made available.

In buildings with a flat roof, an upper basin can also be added relatively easily at a later date 110 retrofit on the flat roof. The solar cells 103 and the solar panels 102 can then be relatively easily installed on the retrofitted upper basin 110 be mounted on the flat roof. The lower pelvis 111 requires either a conversion of the basement, or an external basin, which can be buried underground next to the building, for example.

Thus, in many cases, existing buildings can also be retrofitted in principle.

An alternative embodiment, which is particularly efficient for retrofitting buildings, does not use water, but a solid material that is as dense as possible, such as iron ore.

Iron ore is relatively cheap and has a very high density. In this embodiment, a certain volume of iron ore is placed on a suspension in a shaft. The suspension can be connected to a winch or other lifting mechanism that is electrically powered. Thus, electrical energy, for example from the solar cells 101 used to pull or lift the iron ore up a certain amount within the shaft. When the iron ore is being lowered, a generator can be driven which converts the potential energy of the iron ore into electrical energy.

Such an arrangement of the system can be retrofitted very easily, since no construction work has to be carried out directly on the building or the building structure. Instead, it is sufficient to have a corresponding shaft on the property near the solar cells 101 to retrofit.

The iron ore can furthermore also be used as a heat store by removing thermally insulated flexible hoses from the solar collectors 102 to which iron ore is placed. A pipe system that is as long as possible can then be arranged in the volume of iron ore, which pipe system has the largest possible surface in the iron ore volume. Water coming from the solar panels 102 is heated, can thus be passed through the pipe system in the iron ore and thus heats the iron ore.

The thermal energy stored in the iron ore can then be used via the same water cycle or via a second water cycle to use heat exchangers 210a-d To transport thermal energy into the building.

With the embodiments described above, running costs for the building can be reduced, since no heating costs, no heating system and no electricity costs from external providers are required.

In addition, the heating with water described above can reduce the primary energy requirement of a household by around 80%.

With the invention described herein, an energy storage system can be realized with low use of resources, since no mining of rare earths is required for the production of batteries. In addition, the energy storage system can be scaled as desired together with other buildings and thus enables a larger grouping of decentralized stores for renewable energies when several buildings are connected to one another with the energy storage system of the present invention.

There is also no further environmental destruction for energy storage, since no reservoirs have to be created if many buildings are connected to one another in the manner described above and function as total energy storage. In this way, the invention achieves a genuinely sustainable system in which there is neither a heavy use of resources in the run-up to construction nor problematic waste from the battery after the end of its use. This is particularly advantageous in comparison to conventional energy storage systems in buildings, since electrical battery storage systems are generally used here, the manufacture and disposal of which do very poorly in the environmental balance sheet.

Furthermore, the reusability of the energy storage system according to the invention is not restricted and an infinite number of charging and discharging cycles can be carried out, since there is no upper limit, as is usual with conventional battery storage systems. As a result, there is no aging effect of the storage system, as is known in conventional battery storage systems.

With the invention described above and the embodiments described above, energy self-sufficient households are created and a decentralized network solution is thus made possible. This is particularly beneficial in remote areas of the world.

Even in a larger picture of energy consumption, the present invention can help to noticeably reduce CO2 emissions, since private households in Germany contribute around a quarter of the total primary energy.

Claims (10)

System in a building for converting and storing energy, wherein generated energy is converted and stored both in potential energy and in thermal energy of the same medium, wherein the generated energy comprises electrical energy and thermal energy, the system comprising: an electrical energy source (101), in particular a solar cell arrangement, which is set up to generate and / or output the electrical energy; an energy converter (105), in particular a generator, a pump and / or a turbine, which is set up to: Converting at least a portion of the electrical energy from the electrical energy source into the potential energy of a liquid, and Converting stored potential energy of the liquid into electrical energy; a thermal energy source (102), in particular an arrangement of solar collectors, which is set up to generate the thermal energy, the thermal energy being stored in the form of the thermal energy of the liquid; and a heat exchanger (210a-d) which is configured to receive and / or release the thermal energy of the liquid in a controlled manner. System according to Claim 1 wherein the heat exchanger (210a-d) comprises a heating system for the building. System according to Claim 1 or 2 wherein the energy converter (105) comprises a turbine configured to: pump water from a lower basin (111) to an upper basin (110), and drive a generator to produce electrical energy when water is from the upper basin (110) flows into the lower basin (111). System according to one of the Claims 1 to 3rd , wherein the upper basin (110) and the lower basin (111) are connected to one another via a line (108), the energy converter (105) being connected to the line (108). System according to Claim 4 wherein the conduit (106) further connects the heat exchanger (210a-d) to the upper basin (110) and the lower basin (111). System according to one of the Claims 1 to 5 , wherein the heat exchanger (210a-d) is further configured to release heat for heating or cooling from the water or to conduct it into the water. System according to one of the Claims 1 to 6th , wherein the electrical energy source (101) further comprises a connection to an external power grid (107) and is further configured to: receive electrical energy from the external power grid, and output electrical energy from the energy converter to the external power grid. System according to Claim 7 , wherein the system is implemented as part of a decentralized storage power plant and is set up to store current peaks in the external power grid (107), which are generated in particular by solar energy and wind energy. System according to one of the Claims 1 to 8th , wherein capacities of the electrical energy source (101) and the thermal energy source (102) are designed such that, on average, they generate more energy than an average household consumes. System according to one of the Claims 1 to 9 , whereby the system for storing energy: is a sustainable system which does not require a large amount of resources for its production and which does not leave any problematic waste behind after its use has ended, and does not include any limitation of charge and discharge cycles.

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