System for generating renewable electrical energy and supplying a plurality of consumers

Abstract

The present invention relates to a system for generating renewable electrical energy and supplying a plurality of consumers, comprising a plurality of wind turbines (10, 11) and optionally photovoltaic systems (20, 21) as generators of renewable electrical energy, a plurality of electric-motor-driven vehicles as consumers of electrical energy, a route travelled by these vehicles and a plurality of charging stations (33, 56) arranged at a distance from one another along the route, at which charging stations the vehicles can receive electrical energy, wherein a plurality of wind turbines (10, 11) are installed along the route, wherein the electrical energy generated by these wind turbines (10, 11) is fed into a power line network to which the charging stations (33, 56) are connected, and wherein the system according to the invention further comprises at least one transformer station (18) or at least one transformer (31) and the system is set up to convert the direct current generated by at least one photovoltaic system (20, 21) and / or the direct current or alternating current generated by at least one wind turbine into a three-phase alternating current in the medium-voltage range and to distribute it in the self-sufficient power line network over a longer distance from beyond the at least one transformer (31) or the at least one transformer station (18) to a charging station (33, 56) as current in the medium-voltage range. In this way, the invention creates an energy-optimised self-sufficient system and line network for supplying consumers in the area of, for example, a motorway, with the required electrical energy being generated renewably in the area of the motorway itself.

Description

[0001] System for generating renewable electrical energy and supplying a majority of consumers

[0002] The present invention relates to a system for generating renewable electrical energy and supplying a plurality of consumers, comprising: a plurality of wind turbines and / or photovoltaic systems as generators of renewable electrical energy, wherein the system is configured to supply a plurality of electric motor- or hydrogen-powered vehicles as consumers with electrical energy and / or hydrogen; a plurality of charging stations arranged at a distance from one another along a route traveled by the vehicles, wherein the charging stations are suitable for supplying the vehicles with electrical energy and / or hydrogen, wherein the system further comprises a self-sufficient power line network which is electrically connected to the charging stations and which is fed, optionally exclusively, with the renewable electrical energy generated by the wind turbines and / or photovoltaic systems.

[0003] State of the art

[0004] It is generally known from the prior art to generate renewable electrical energy via wind turbines and use it to charge the batteries of electric vehicles. For example, EP 3 659 854 A1 proposes a method for using a charging unit and a transport system for charging units. In this method, charging stations charged with renewable energy from wind power are transported by trucks that accommodate multiple charging stations to an area, such as a public parking lot or the like, where they can then be used by car drivers to charge the car batteries.This system is comparatively cumbersome, firstly because it requires specially trained trucks that pick up the charging units at the location where wind energy is generated, i.e. at the site of a wind turbine, and transport them by road to a location where the charging units are set up and made available to cars. The charging units must be loaded by crane. The trucks transport the charging units by road to the locations where charging stations are located. This takes time, consumes energy to power the trucks, and also pollutes the environment due to the trucks' CO2 emissions. In addition, large conventional wind turbines are used to generate renewable electrical energy, which are only available in certain locations, meaning that the distances to the charging stations where the energy is needed to charge cars can be great.Large wind turbines of this type require a complex approval process, so that it is not possible to erect further such wind turbines in the short term at a location near a traffic route, such as a motorway, which is used by many electric vehicles.

[0005] It is also known to use renewable energy generated by photovoltaics to charge the batteries of electric vehicles. For example, DE 20 2011 100 046 U1 describes a system in which the roofs or sides of trucks or rail vehicles are equipped with photovoltaic systems, converting solar radiation into electrical energy on these vehicles. The renewable energy thus generated is stored in batteries, which are then transported to energy collection points. At these energy collection points, the charged energy storage units can be delivered to vehicles and exchanged for empty vehicle batteries.

[0006] Apart from the systems mentioned above, wind power is traditionally generated in large turbines with nominal outputs of around 2 MW to 5 MW, or more in the case of large offshore turbines. The trend today is towards building increasingly larger wind turbines in order to achieve higher output. These large turbines have various disadvantages. For example, the diameter of the rotor blades in a 2 MW turbine is already over 100 m, so the total height including the rotors is well over 100 m. The weight of a large wind turbine can be more than 1000 t, so large foundations are necessary during its construction. A further problem is the high level of noise, which is why a minimum distance of 1.5 km from the nearest residential area is currently prescribed.Furthermore, these systems must undergo a complex approval process, and since public acceptance of these systems is declining, it often takes several years to obtain approval for and construct a new system. Furthermore, the electricity generated by wind turbines is usually fed into the general power grid. Wind turbines are often located in sparsely populated rural areas, and the electricity must then be transported over long distances via high-voltage lines to locations with high energy demand, such as larger cities, industrial facilities, and the like. Firstly, transmission over long distances results in line losses in the power grid.Another problem is that the electricity generated by wind turbines is intermittent. During strong winds, a comparatively high level of wind power is generated, but this often does not meet the corresponding energy demand. Conversely, during calm winds, there is insufficient wind energy available. This requires either the excess electricity generated during strong winds to be stored in a suitable form, or energy is lost during high winds because it cannot be fed into the public grid.

[0007] The present invention is based on the following considerations. In order to reduce CO2 emissions in the transport sector, it is planned to convert private transport to electrically powered vehicles over the next twelve years. From 2035, no new vehicles powered by conventional diesel or gasoline combustion engines will be registered in the EU. This means that the demand for electrical energy along motorways and main roads will increase considerably compared to today. Although there are plans to gradually increase the share of renewable energies in the supply of electrical energy, since the approval of large wind turbines near residential areas is met with considerable resistance from the population, it is questionable whether demand can be met by wind turbines to a sufficient extent and within the envisaged time frame.When larger wind farms are built offshore, considerable distances must sometimes be bridged to transport the electricity to the long-distance routes, for example in southern Germany. Furthermore, it makes little sense to select sparsely populated areas for the construction of wind turbines, areas with intact natural surroundings that would be negatively impacted by the wind turbines (deforestation, disturbance of birdlife, noise pollution, etc.). On the other hand, major traffic routes such as motorways and highways already exist in areas where noise pollution is high and natural surroundings have been disrupted by the destruction of green spaces. Areas adjacent to motorways are hardly usable for human settlements and are also unsuitable habitats for wildlife due to the noise and danger posed by vehicles.The basic idea of ​​the present invention is therefore to use these areas adjacent to roadways for the generation of the electrical energy from renewable sources that is required by the vehicles in the area of ​​the roadways.

[0008] The publications US2018 / 0254736 A1 and US2021 / 0126574 A1 disclose systems of the type mentioned above, in which photovoltaic systems and wind turbines are installed along a route to generate electricity from renewable sources and charge the batteries of electric vehicles traveling along the route. The photovoltaic systems are installed on noise barriers, barriers, or crash barriers located along the route. However, these publications lack concrete information on how to configure the transmission grid for the renewably generated electricity so that it is transmitted along the route from the generators to the charging stations where the electricity is consumed with as little loss as possible and with reasonable technical effort.

[0009] Based on the aforementioned prior art, the object of the present invention is to provide a system for generating and using renewable energy with the features mentioned at the outset, which is optimized in terms of energy technology and line technology with regard to the power transmission from the generators to the electrical consumers.

[0010] Approach of the present invention

[0011] The solution to the above-mentioned problem provides a system for generating and using renewable electrical energy of the type mentioned above with the features of claim 1.

[0012] According to the invention, the system further comprises at least one transformer station or at least one transformer, wherein the system is configured to convert the direct current generated by at least one photovoltaic system and / or the direct current or alternating current generated by at least one wind turbine into a three-phase alternating current in the medium-voltage range and to conduct it in the self-sufficient power line network over a longer distance from beyond the at least one transformer or the at least one transformer station to a charging station as current in the medium-voltage range.

[0013] If the above wording states "that the system is designed to convert the direct current generated by a photovoltaic system or the direct current or alternating current generated by a wind turbine into three-phase alternating current in the medium-voltage range," this means that either the transformer station or transformer mentioned is suitable for this purpose, or that the system, in addition to a transformer station or transformer, may comprise further power processing devices. These devices may, for example, include at least one frequency converter to convert, for example, alternating current generated by a wind turbine into alternating current at a different frequency, for example, the common grid frequency of 50 Hz.Such alternating current at mains voltage can then be converted into direct current via at least one rectifier in the transformer station or, for example, in the line path upstream of it, and then stepped up to the desired voltage in the medium-voltage range. Photovoltaic systems already supply direct current, so this current only needs to be stepped up in the system to the desired voltage in the medium-voltage range, which is intended for the power transmission in the system's self-sufficient power grid.

[0014] The above formulation "in the autonomous power line network over a longer distance from beyond the at least one transformer or the at least one transformer station to a charging station as electricity in the medium voltage range" means that the conversion into the desired direct current takes place either in the transformer station or the transformer or, if necessary, partly beforehand, but at the latest in the transformer station or the transformer this direct current in the medium voltage range is generated and from there is transmitted in the autonomous power line network as electricity in the medium voltage range to a charging station of the system.

[0015] The transformer station is located in the line route between the generator and the charging station. The invention involves conducting the electricity as direct current in the medium-voltage range over the length of the line route from the transformer station or from the transformer to the charging station. The above phrase “over a longer distance” means that this is generally a distance of at least one kilometer, generally a distance of several kilometers, for example a distance in the range of approximately 1 km to approximately 50 km, preferably from approximately 5 km to approximately 25 km. This distance corresponds at most to the line route between one or more power generators and the nearest charging station in the system where the electricity is to be made available. The transformer station or transformer may be located a short distance (for example less than 1 km) from the power generator(s).The transformer station or transformer can also be located at a distance of several kilometers, for example, 2 or 3 kilometers, from the generators. However, this distance should not be too long, since the invention is intended to transmit the power line to the nearest charging station as a low-loss medium-voltage direct current. As a rule, the distance between the generators and the transformer station or transformer will therefore be (significantly) shorter than the distance to the nearest charging station.

[0016] The aim of the invention is to provide charging stations along the route at regular intervals, i.e. the line path in the self-sufficient power line network along the route is segmented into individual sections that correspond to the respective distance from one charging station to the next.

[0017] To give an example: If, for example, the distance between a first and a second adjacent charging station along the route is 20 km, the feed-in of renewable electricity occurs in the power line path near the first charging station, and a transformer station or a transformer is located at a distance of, for example, 500 m from the feed-in point, then the power line as medium-voltage direct current in the autonomous power line network from beyond the transformer station or transformer to the second charging station would be 20.5 km. Preferably, however, there will be several generators along the route section leading from the first to the second charging station, so that the power line path of the medium-voltage direct current coming from these generators is shorter than the aforementioned 20.5 km.

[0018] Nevertheless, the system should be configured to transmit medium-voltage direct current over the entire route, corresponding to the distance between two charging stations. For example, if the route is a motorway, charging stations should preferably be located at at least every rest area. If the distances between two rest areas are too large, it is preferable to also provide charging stations at parking lots, which are generally closer on motorways, as they are located between rest areas. Parking lots on motorways are easily suitable for charging electric vehicles if the area is large enough.

[0019] In the context of the present invention, direct current in the “medium voltage range” is considered to be a direct current of preferably at least about 800 volts up to about 20 kV.

[0020] Such a self-sufficient power grid, as part of the system in which renewable energy is generated, offers several advantages. Firstly, this self-sufficient power grid can be designed according to demand, meaning it is calculated and dimensioned in such a way that electrical energy is always available in the area of ​​the routes at least equal to the amount consumed by the vehicles using the routes during peak times. Renewable energy is generated where it is consumed, resulting in short power line routes and thus minimizing energy losses.The areas along the roads, some of which are already sealed, are not suitable as residential areas or near-natural areas anyway, so that no further interventions in nature are necessary for the installation of the energy generation systems, the power lines and, if necessary, storage facilities, and no valuable natural areas are used up.

[0021] Any storage facilities required in the system when more electricity is temporarily generated than consumed can also be built as part of the system, close to the roadway. The same applies to charging stations, which can be installed at existing parking lots and rest areas, for example, so that no further natural areas need to be destroyed.Both the wind turbines and photovoltaic systems as producers of renewable electrical energy, as well as storage devices in the form of accumulators or, for example, tanks in which electrolytically produced hydrogen or, where appropriate, methane, LPG, methanol or ammonia is stored, which were generated in the system using the renewably produced electricity, can be arranged in the periphery of the tracks, as can electrical lines, overhead lines and other line systems required in the system, such as pipelines for hydrogen, LPG or other energy-rich liquids, and are thus part of the self-sufficient system.

[0022] A further advantage of the solution according to the invention is that the existing power grid outside the system is relieved, since the long-distance power lines from, for example, offshore wind farms to the roadways are no longer required.

[0023] As a rule, the state already owns the land on and near the roads (highways and federal highways), so that the installation of all necessary facilities for the system can be carried out in the short term without the need to acquire land and long-term legal disputes with third-party owners.

[0024] The invention thus takes a different approach than the prior art mentioned at the outset, in which wind turbines located far away from the charging stations are used to generate renewable energy and in which either entire charging stations or the batteries for the vehicles have to be transported to electric charging stations in order to charge electric vehicles or replace the batteries.

[0025] According to the present invention, a "charging station" is understood to be an area such as a parking lot or rest area along a motorway or major country road, where—in addition to the actual "charging stations" themselves—buildings serving as consumers and other infrastructure such as transformer stations, substations, etc. can be located. This has the advantage that not only the charging stations but also the buildings, such as restaurants, gas stations, etc., can be supplied with the electrical energy generated along the route.According to the invention, a separate power line network is thus preferably created, which can, for example, be independent of the public supply network and supply only one charging station at a time, for example a service area, but which can also be connected to the public power grid if necessary, so that surplus quantities of electrical energy that are not consumed in the area of ​​the charging station can be fed into the public power grid or, for example, can also be used to supply villages or individual houses that are located near the route with electrical energy.

[0026] The present invention is based on the consideration that when using renewable energy to charge vehicle batteries, it is advantageous to select the location where this energy is generated as close as possible to the location where the energy is consumed. Most passenger cars and trucks use motorways or major country roads. The traffic volume on motorways and major country roads can be estimated quite accurately based on comparative values. In a highly developed industrial country with good infrastructure, such as the Federal Republic of Germany, these transport routes are found almost nationwide in a dense road network. Since this network of the busiest roads extends over a total of thousands of kilometers, a large area is available in the immediate vicinity of the roads. This area can be used for the construction of wind turbines and, if necessary, solar panels.The invention proposes the installation of wind turbines, possibly even small wind turbines, near a highway or major country road. This has the added advantage that, with a total height of up to 10 m, they are not subject to building permit requirements. The installation and assembly of such a small wind turbine is also less complex than that of a large wind turbine, as the individual components are smaller and lighter, making them easy to transport by vehicle. Furthermore, the effort required to construct large foundations is eliminated.

[0027] The idea of ​​a self-sufficient power grid along highways or other major roads has the further advantage that this power grid is controlled by the state and not owned by a large number of different industrial, regional, or municipal energy producers. For example, a consortium of companies commissioned by the state or a state-owned company could operate the system according to the invention, similar to the case in rail transport. Renewably generated electricity, for example, can be electrolytically converted into hydrogen, allowing vehicles equipped with fuel cells to refuel with hydrogen in the system. Vehicles equipped with metal hybrid storage systems can also be supplied with hydrogen.

[0028] A further advantage of the system is that it can be monitored and secured much better than the existing, very complex, public power grid, which has numerous regional owners of the lines and power lines that run across the properties of countless different (third-party) owners.

[0029] Small wind turbines, for example, require little space and can be installed close to each other and to the road. Their noise level is also low and is hardly perceived as disturbing. Small wind turbines with a rotor diameter of up to 3 m, for example, can produce an output of around 5 kW or more. If 1,000 of these small wind turbines are installed along a stretch of motorway, they will generate the same electrical output as one large 5 MW wind turbine. If the small wind turbines are positioned at a distance of, say, 20 m from each other in three parallel rows, for example, along the sides of each lane and on the central reservation, 50 x 3 = 150 such turbines can be installed per kilometer of motorway. With just 5 kW per turbine, this equates to an output of 750 kW per km of motorway.It makes sense to install charging stations for electric vehicles at parking lots and rest areas, as vehicles can easily stop there. The entire motorway network in Germany is approximately 13,000 km long. Parking lots are located at an average distance of less than 10 km. If, for simplicity, a distance of 10 km is assumed, then in the above example calculation, an electrical output of 7.5 MW can be achieved from the small wind turbines alone for both lanes of a motorway between two parking lots. This means that with parking lots on both sides of the motorway, 3.75 MW of installed capacity would be available on each side for charging vehicle batteries and, if necessary, other consumers.

[0030] Based on the entire 13,000 km motorway network, this would result in a capacity of 13,000 x 750 kW = 9.75 GW. Assuming, for example, 5,000 hours of full use, this would be 9.75 million kW x 5,000 h = 9.75 billion kWh. The total annual electricity consumption of the Federal Republic of Germany is approximately 600 billion kWh, so the small wind turbines alone in the system proposed along the motorway could supply approximately 1.6% of Germany's total energy consumption.

[0031] According to a preferred development of the invention, photovoltaic systems and, if appropriate, wind turbines connected to the system's autonomous power grid can be installed near the route, particularly in rows on a shoulder next to a roadway and / or on the median between two roadways. By combining wind turbines and photovoltaic systems, the total electrical power available from renewable energy sources at the charging stations can be further increased.

[0032] Some motorways or country roads may be located on lower ground. In these cases, according to a preferred embodiment of the invention, it is advantageous if the wind turbines are installed on a lower-lying road compared to the surrounding area at a location elevated relative to the road, close to the road, where the rotors of the small wind turbines are sufficiently exposed to the wind. Typically, there is an embankment next to the road, allowing the wind turbines to be installed in the upper part of the embankment, with the rotors projecting above the embankment and thus receiving optimal wind exposure. In these cases, too, the wind turbines are installed "close to" and along the road within the meaning of the invention.

[0033] According to a preferred development of the invention, at least one photovoltaic system, which is electrically connected to the autonomous power line network of the system, is arranged on a traffic sign or information board on or near the roadway and / or a photovoltaic system is arranged on the roadway and / or the roadway is at least partially designed as a photovoltaic system.

[0034] The photovoltaic systems, which according to the invention are optionally additionally installed near and along the roadway, can be installed either close to the ground with an appropriate incline and preferably facing south. Here, too, there is the advantage that the land along the roadway is owned by the state or, if appropriate, in the hands of a single owner, provided that, as in countries such as France or Italy, a private company operates the motorway. Furthermore, according to a preferred embodiment of the invention, it is possible to arrange at least one photovoltaic system, which is electrically connected to the power grid, in the area of ​​a shoulder next to a roadway and / or on the central reservation between two roadways and / or on a traffic sign or information board on or near the roadway.With the existing traffic signs and information boards, additional areas are available where the installation of photovoltaic systems is possible with relatively little technical effort, provided they are appropriately aligned.

[0035] An additional option is to equip the roadway itself with photovoltaic systems or to design it as a photovoltaic system. Road surfaces are already known that can convert solar energy into electrical energy and that are sufficiently resilient to support weight, making them suitable for use as a roadway. It is therefore technically feasible to use the roadway itself as a photovoltaic system and thus as an additional source of renewable energy.

[0036] According to a preferred development of the invention, at least one photovoltaic system, which is electrically connected to the power grid, is arranged on a noise barrier next to the roadway. Such noise barriers are available, particularly when a motorway runs through a residential area or is located near populated areas, and offer large areas for the installation of photovoltaic systems. Additional systems can be installed, for example, on surfaces of existing structures such as bridge railings or on the front sides of underpasses. In all of the aforementioned cases, an advantage arises from the fact that the invention can use areas for the installation of photovoltaic systems that are already part of the existing infrastructure near roads such as motorways and major country roads and that can be owned by the state or the motorway operator.This reduces installation costs and eliminates the need to purchase electricity from a private operator of a larger photovoltaic system, as has sometimes been the case with privately operated photovoltaic systems, for example, on agricultural land. The invention also leverages the additional cost advantage that the power grid into which the renewably generated electricity is fed can be kept significantly shorter, as this power grid can be laid along the roadway and thus in the immediate vicinity of the installed small wind turbines or photovoltaic systems, and from there can be routed to the charging stations.

[0037] According to a preferred development of the invention, the system according to the invention comprises at least one transformer station, wherein the electricity generated by at least one wind turbine is converted into three-phase alternating current, preferably in the low-voltage range. Such a transformer station can be used, for example, to initially standardize the electricity generated by the wind turbines on the one hand and by the photovoltaic systems on the other, so that it can then be transmitted via a common power grid of the system. For example, this uniform electricity from all renewable generators can then be further transformed from a low-voltage range to a medium-voltage range in order to then transmit the electricity over a longer distance with lower losses, in particular to the charging station in whose area the electricity is supplied to the consumers.

[0038] According to a preferred development of the invention, the system comprises at least one transformer station, wherein the electricity generated by at least one photovoltaic system, which in this case is direct current, is converted into a three-phase alternating voltage, preferably in the low-voltage range, fed into the power grid, and transmitted further. According to this variant of the invention, both the electricity generated by wind power and the electricity generated by solar energy are each converted into three-phase alternating voltage, preferably at the same frequency, in particular at the usual grid frequency of 50 hertz, wherein the voltage is particularly preferably approximately 400 volts in each case, which is the usual three-phase alternating voltage classified as low-voltage.In this way, electricity with the same parameters is obtained from both energy generators and can be fed uniformly into a transmission system through which the electricity is transmitted to the consumers, particularly in the area of ​​the nearest charging station.

[0039] According to a preferred development of the invention, the power grid into which the electricity generated by at least one wind turbine and optionally by at least one photovoltaic system is fed comprises at least one transformer, preferably at least one transformer station, in which low-voltage three-phase alternating current is converted into medium-voltage current. Instead of such a transformer station (which could also be referred to as a type of substation), a single transformer, for example, can be arranged in a substation along the line path from the energy generator to the consumer.

[0040] The system works as follows: The wind turbines generate alternating current, preferably on the low-voltage side (e.g., three-phase current at 400 V), which can be fed to a transformer station. If necessary (usually), a frequency converter is used to convert the frequency of the power generated by the wind turbine to the standard grid frequency of 50 Hz. Such a frequency converter can be integrated into the wind turbine. The photovoltaic systems generate direct current, which is also converted, for example, in a transformer station via an inverter into low-voltage three-phase current. This three-phase current can be converted via a transformer to a medium voltage in the range of, for example, 10 kV to 20 kV (or higher) and then transported over a distance of, for example, 1 km or several kilometers to a charging station.These distances depend, among other things, on the distances between the charging stations, the number of renewable energy producers feeding in electricity, and whether only one or several transformer stations (substations) are planned between each two charging stations.

[0041] According to a preferred development of the invention, the power line network according to the invention is designed to conduct electricity over a longer distance from beyond at least one transformer station to a charging station as medium-voltage electricity. Thus, within the framework of the system according to the invention, a dedicated power line network is preferably used, which is configured according to the needs of the system. In principle, it is of course also possible to use parts of an existing public grid instead of a dedicated power line network. As a rule, however, no suitable public grid lines are available in areas along a motorway or major country road. To date, the public power grid has only supplied service areas or, where appropriate, parking lots where charging stations for electric vehicles are already located.Therefore, cables would have to be laid anyway, leading from the renewable energy generators to the charging stations. Therefore, it makes sense to install a separate power grid for this purpose, which meets the requirements of the system described above.

[0042] According to a preferred development of the invention, at least one charging station is located in the area of ​​at least one rest stop or parking lot located along the route. As already explained above, a charging station is understood to mean the entire area, which may include a type of electric charging station with charging columns for cars and trucks, optionally swap stations where empty batteries can be exchanged for charged ones, which may further include a conventional filling station for gasoline and diesel, restroom facilities, parking spaces, recreational areas, possibly restaurants, etc., i.e., the corresponding infrastructure as found at conventional parking lots or rest stops, for example, on highways.Thus, in addition to the charging columns and, if applicable, swapping stations specifically designed for electric-powered vehicles, the charging station generally also includes a number of other electrical consumers. The system according to the invention is particularly preferably configured so that the entire power requirement of such a charging station, with or without a rest stop, can be covered by the power generated from renewable energy, which is fed to the charging station via the power grid according to the invention. In this ideal case, the charging station is thus energetically self-sufficient and does not require a connection to the public power grid. This ensures that the entire charging station is supplied exclusively with renewable energy, whereby this renewable energy can be generated entirely within the system itself, meaning that no conventional large-scale wind turbines, solar systems, or hydroelectric power plants need to be additionally constructed.Ultimately, the route itself, especially the motorway or major country road, is the energy supplier for the energy requirements of the route, with no environmental pollution caused by CO2 emissions during energy production.

[0043] The advantage here is that the system can be designed and configured in such a way that the energy requirements of a charging station along the route can be covered by the renewable energy generated along the section of the route between two charging stations, even in adverse weather conditions (calm wind, cloud cover). If, under favorable conditions, more energy is generated than the charging station requires, at least one energy storage device can be provided near at least one charging station, which is suitable for storing excess renewable electrical energy generated in the system.Or the surplus electrical energy can be redirected to residential areas, individual buildings, industrial facilities, commercial areas, or similar areas located near the route and / or one of the charging stations, allowing these additional consumers to be integrated into the system's power grid without the excessive expense of laying electrical cables over long distances. Instead, a suitably designed line emanating from one of the charging stations or branching off from a line at a suitable point along the route is sufficient. Depending on the distance to these additional consumers, the electricity from the system's power grid can be transmitted to the additional consumers at medium or low voltage.The construction of additional high-voltage lines / high-voltage pylons and / or substations is therefore not necessary in order to supply additional consumers, for example in remote areas, via the system according to the invention.

[0044] Such a self-sufficient power grid, for which the energy is generated renewably within the system and the power is tailored to the needs of consumers present along a defined route of the system in the area of ​​a charging station or outside of it, can be designed, calculated and utilized much better than with the previous use of the public power grid, which has much larger dimensions, countless energy feeders and countless consumers with time-dependently variable energy requirements and is thus heterogeneous and unmanageable.

[0045] According to a preferred development of the invention, the system comprises at least one transformer or transformer station in the line path from the generator to the consumer upstream of a charging station, by means of which an alternating current in the medium-voltage range can be converted into a three-phase alternating current in the low-voltage range. The line path of usually several kilometers, for example 1 km to 10 km or 1 km to 5 km, from the generator or a transformer station to a charging station can thus be covered with alternating current in the medium-voltage range, for example 10 kV to 20 kV, thereby reducing line losses. At least one transformer is then provided that converts the current back into an alternating current in the low-voltage range, so that the current required by the consumers at the charging station is available in the low-voltage range, for example 400 volts.

[0046] According to a preferred embodiment of the invention, a charging station comprises at least one charging column for charging vehicle batteries, wherein preferably at least one additional consumer, in the vicinity of the charging station or remotely from the charging station, is supplied by the power grid into which the renewably generated energy is fed. This additional consumer can be, for example, a gas station or a restaurant on the premises of the charging station, or one or more external consumers such as buildings, a residential area, or a commercial area near the charging station.

[0047] According to a preferred development of the invention, at least one rectifier is provided in the area of ​​a charging station, preferably in the area of ​​a line leading to a charging column or in a charging column, and is configured to convert low-voltage three-phase current supplied by the power grid into direct current suitable for charging batteries. This can then, for example, provide a rapid charging station via which the batteries of electric vehicles are charged directly with direct current. At least one further charging station can, for example, be designed as an AC charging station, so that it is alternatively also possible to charge vehicles with alternating current, which is then converted into direct current for the battery via a device installed in the vehicle.

[0048] According to an alternative preferred variant of the invention, at least one rectifier is arranged in the power flow from the generator to the consumer, that is to say in the power flow from at least one wind turbine or a photovoltaic system to a consumer in the area of ​​a charging station, and is designed to convert the electrical energy generated by the small wind turbine into a direct current in a technically reasonable voltage range of in particular approximately 800 volts to 1200 volts, for example approximately 1000 V, wherein the power line network in the power flow from the generator to the consumer beyond this rectifier up to preferably the nearest charging station is designed to conduct direct voltage in a medium voltage range.With this variant, for example, direct current can first be fed from the wind turbine to an inverter, to which the cables coming from the photovoltaic systems can also be connected, thus initially producing low-voltage three-phase alternating current of, for example, 400 V. This can then either be converted via a transformer into a medium-voltage current, which is transported via the line to the next charging station to reduce line losses, and then transformed there back into a low-voltage current suitable for supplying the loads. Or the low-voltage current can be used directly if suitable loads are nearby.

[0049] Further advantages of the system according to the invention for generating renewable electrical energy and supplying a multitude of consumers lie in the fact that, if necessary, additional peripheral properties adjacent to the motorway route can be included as sites for the installation of renewable energy generation systems, even if these properties are not owned by the motorway operator. In principle, larger wind turbines could also be installed there, which no longer fall under the definition of small wind turbines (total height up to 10 m), and the electricity they generate could be fed into the power grid of the system according to the invention.This is advantageous compared to today's conventional approach, where such properties adjacent to the roadway have usually already been cleared and are generally not considered for alternative use (e.g., residential development) due to noise pollution and other vehicle emissions. This approach allows for the generation of additional renewable energy. From an ecological perspective, this solution is significantly better than, for example, erecting wind turbines in forested areas or other areas with intact nature, thereby destroying or harming the flora and fauna there. This is especially true since remote, near-natural areas generally lack an electrical grid, making the laying of cables to connect the energy generator to the public grid much more costly.Furthermore, the properties adjacent to a motorway route are less attractive for alternative uses and can therefore be acquired more cheaply. The motorway route and the adjacent properties on which the renewable energy generators and the power grid of the system according to the invention will be built thus form a technology route where the destruction of intact nature can be reduced to a minimal area on both sides of the route.

[0050] Since the power line network belonging to the system is laid directly or as close as possible along the route of a motorway or country road, electricity generated from renewable energy is also available at low cost to other consumers along or on the route, i.e. to consumers that are not located in the area of ​​one of the charging stations, for example lights for illuminating signs, power for sensors or display systems.

[0051] Since the main line of the power grid according to the invention is preferably routed from the generators to the charging stations along both sides of the highway, this ensures that the power line is as short as possible, and power is available everywhere, for example, for information systems. Preferably, the renewable generators of the system are arranged in a line along the route, just as the consumers can be arranged in a line along the route. Thus, the cables of the power grid run along this line defined by the route and can be designed as short as possible.

[0052] A further advantage of the invention is that it reduces the risk of sabotage, which is a serious problem in current times of crisis. For example, offshore wind turbines, power lines laid on the seabed, and overhead lines with pylons running hundreds of kilometers through remote areas, as currently used, are vulnerable to sabotage. Lines laid along busy roads, especially underground, are less vulnerable and can be better monitored by suitable devices. These monitoring devices can, in turn, be powered by renewable energy generated from the system.

[0053] In summary, the present invention provides an autonomous, self-contained system that is linearly routed along a track and has a minimized footprint. It includes components for power generation, power transmission, and power supply, as well as power consumers in the form of electrically powered vehicles and infrastructure components along the track. The system is designed to be environmentally friendly and independent of the fragile and complex structures of the general power grid, and it compresses the components for the electrical supply of the vehicles and the track into a small space.

[0054] According to a preferred development of the invention, the system comprises at least one device for the electrolytic production of hydrogen by means of regenerative electrical energy generated in the system and at least one device for storing hydrogen, for example a hydrogen tank or a metal hybrid storage device.

[0055] Alternatively, electrolytically produced hydrogen can be converted into another energy source by chemical reaction, which can be stored in liquid form, possibly under pressure, or as a gas, for example in appropriate tanks, with energy-rich compounds such as methane, LPG, methanol, ethanol or ammonia being particularly suitable here.

[0056] If the production of hydrogen or the aforementioned energy carriers is planned at a location remote from a charging station, the system according to a preferred embodiment of the invention comprises at least one pipeline for transporting hydrogen or the energy carrier from the production site to a charging station. At the charging station, vehicles with appropriately configured drive systems can then be directly refueled with hydrogen or the energy carrier, for example, via suitable refueling equipment.

[0057] According to an alternative variant of the invention, even if, for example, excess energy is generated in the system, energy stored in the form of hydrogen or one of the aforementioned energy sources can be converted back into electricity, for example in the vicinity of a charging station, to supply electrically powered vehicles. This makes it possible to use the regenerative electrical energy generated in the system to supply both electrically powered vehicles and vehicles with hydrogen tanks or fuel cells, as well as vehicles fueled with methanol or methane.

[0058] Concrete embodiments of the present invention

[0059] The present invention will be explained in more detail below using specific embodiments with reference to the accompanying drawings.

[0060] Figure 1 is a schematically simplified representation of a first exemplary embodiment of a system according to the invention;

[0061] Figure 2 is a schematically simplified representation of an exemplary alternative embodiment of a system according to the invention;

[0062] Figure 3 is a schematically simplified representation of a detail of the design of an exemplary system according to the invention in the area of ​​a charging station.

[0063] A first possible embodiment of the present invention will now be explained in more detail with reference to Figure 1. Figure 1 shows a simplified schematic representation of an exemplary circuit diagram of a system according to the invention for generating renewable energy. As generators of renewable energy, the system comprises a plurality of wind turbines 10, 11, two of which are shown here as examples. These wind turbines 10 convert mechanical energy into electrical energy through the rotation of their wind-powered rotors. Frequency converters 13 are generally connected downstream of the generators 12, which convert the generated electricity to a standard grid frequency of, for example, 50 Hertz, so that three-phase current in the low-voltage range of, for example, 400 V can be fed into the system's power grid via lines 14, 15 and conducted to a transformer station 18.The lines 14, 15 of the individual wind turbines 10, 11 are generally each connected to the grid via switches 16, 17 in the area of ​​the transformer station 18, so that they can be individually switched on or off as the system requires renewable energy. Furthermore, the system according to the invention generally comprises a large number of photovoltaic systems 19, 20, 21, each with several module groups, of which three photovoltaic systems 19, 20, 21 are shown as examples in Figure 1. These initially each generate direct current, for example in a voltage range of approximately 200 V to approximately 800 V, which is fed into the power line system according to the invention via lines 22, 23, 24 and initially conducted to an inverter 25, by means of which the direct current is converted into three-phase current in the low-voltage range of, for example, approximately 400 volts.A switch 26 is also generally arranged between the inverter 25 and the input side of the transformer station 18, so that the additional renewable electricity generated by the photovoltaic systems 19, 20, 21 can be fed to the power grid as required, or these systems can also be disconnected from the power grid.

[0064] The transformer station 18 or conversion station comprises a busbar 27, to which the lines 14, 15, which conduct the current from the wind turbines 10, 11 to the transformer station 18, can be connected via the switches 16, 17. Furthermore, the inverter 25 is connected to the busbar 27 via the line 28 and the switch 26, so that the current generated by the photovoltaic systems 19, 20, 21 on the low-voltage side, in particular as three-phase current at 400 volts, can also be fed into the busbar 27. The busbar 27 is connected on the output side via a switch 29 and the line 30 to the input side of a transformer 31. This converts the three-phase current fed in on the low-voltage side, for example, into a current with a medium voltage in the range of 10 kV to 20 kV, which can then be transmitted via line 32 to the next charging station 33.

[0065] An alternative exemplary embodiment of the invention is explained below with reference to the simplified schematic representation in Figure 2, wherein Figure 2 shows only a part of the system according to the invention, which relates to the design of the wind turbines. A large number of wind turbines 10, 11 are present, of which only two are shown in Figure 2 as examples. Downstream of the generators 12 of the wind turbines 10, 11, in the power path from the generator to the consumer, rectifiers 34 are connected via which a direct current in a medium voltage range of, for example, approximately 1000 V or more is generated, which is then fed via lines 35 and 36 to a transformer station 18. The current generated by the photovoltaic systems 19 (not shown in detail here) is also fed to an inverter 25 of this transformer station 18.This direct current from all renewable generators is first converted into three-phase current of, for example, 400 volts by the inverter 25 and then transformed by the transformer 31 into current with a medium voltage in the range of, for example, 10 to 20 kV and thus transmitted with low losses via the line section to the next charging station 33 and, if applicable, to other consumers in the area of ​​a service station or nearby buildings.

[0066] An exemplary embodiment of the design of a charging station 33 and rest stop is explained in more detail below with reference to Figure 3. Figure 3 shows, as a schematic sketch, some examples of consumers in the area of ​​a charging station 33, which is supplied with renewable energy, which is generated, for example, in the system according to the description of Figures 1 or 2, using wind turbines and photovoltaic systems. As explained there, the current is preferably supplied from the generators 10, 11 to the charging stations 33 at a medium voltage in the range of, for example, 10 kV to 20 kV. Via the output line 32 shown top right in Figure 1, the current reaches a busbar 37 upstream of the charging station 33 on the input side, to which busbar 37 several of these 10 kV medium-voltage lines 32 can be connected.These could be, for example, lines 38 from the stations to the left of the track, lines 39 from the stations to the right of the track, and, if necessary, additional lines 40 for externally feeding in additional regeneratively generated electricity. Such external feeding into the system is useful, for example, if wind turbines or photovoltaic systems are already installed near the track, which were installed before the system was set up, and whose regeneratively generated electricity can be incorporated into the system's power grid. These lines 38, 39, and 40 leading to busbar 37 are each connected to busbar 37 via switches 41, 42, and 43, so that the individual lines can be connected to or disconnected from it as needed.

[0067] From the medium-voltage busbar 37, a line 45, which can be disconnected via a switch 44, initially leads to a transformer 46 or a transformer station, in which the current is converted into a low-voltage three-phase current of, for example, 400 volts. The low-voltage output line 47, in turn, can be shut off via a switch 49 and leads from the transformer station 46 to another low-voltage busbar 48. Various consumers in the area of ​​a charging station or in a nearby external area can be supplied with power via this busbar 48. For example, a rectifier 51 can be connected to this busbar 48 via a switch 50, which rectifier generates direct current to supply one or more batteries 52, so that renewably generated electricity that is not immediately consumed can be stored in the batteries 52.If necessary, electricity stored in the batteries 52 can be drawn and converted into three-phase current of, for example, 400 volts via an inverter 53 and fed to the busbar 48 via switch 54. Various consumers are connected to this busbar 48, to which the renewable electricity generated in the system can be supplied. As an example, Figure 3 shows a charging station 56 and two further consumers that can be supplied with three-phase current of, for example, 400 volts via the busbar. The lines to the various consumers can generally be separated from the system's power grid via switches. For example, a charging station 56, at which vehicles can charge their batteries, is connected via switch 55.Additional consumers can draw power from the busbar via any number of additional lines and additional switches, whereby, for the sake of simplicity, only two additional consumers are shown in Figure 3. These receive power via switch 57 and line 58 or via switch 59 and line 60, respectively. The consumers are each connected to each other via lines 58 and 60 and also to the charging station 56 in parallel to the busbar 48.The consumers can be, for example, facilities in the area of ​​the charging station 56, such as a petrol station or service area, or infrastructure facilities along the motorway route, such as illuminated signs, electronic traffic control systems or the like, or even individual buildings, settlements, industrial sites that are located near the route, a transformer station 46 or a charging station 56 and can thus be supplied with renewable energy via the power line network of the system according to the invention at a reasonable cost.

[0068] List of reference symbols

[0069] 10 first wind turbines

[0070] 11 additional wind turbines

[0071] 12 Generator

[0072] 13 frequency converters

[0073] 14 Three-phase current line

[0074] 15 Three-phase current line

[0075] 16 switches

[0076] 17 switches

[0077] 18 Transformer station

[0078] 19 first photovoltaic system

[0079] 20 second photovoltaic system

[0080] 21 third photovoltaic system

[0081] 22 Line

[0082] 23 Line

[0083] 24 line

[0084] 25 inverters

[0085] 26 switches

[0086] 27 Busbar

[0087] 28 Line

[0088] 29 switches

[0089] 30 Line

[0090] 31 Transformer

[0091] 32 Line

[0092] 33 charging stations

[0093] 34 rectifiers

[0094] 35 Line

[0095] 36 Line

[0096] 37 Busbar

[0097] 38 Line

[0098] 39 Management

[0099] 40 Cable for external supply

[0100] 41 switches

[0101] 42 switches

[0102] 43 Switch 44 Switch

[0103] 45 Line

[0104] 46 Transformer station

[0105] 47 Output line

[0106] 48 low-voltage busbar

[0107] 49 switches

[0108] 50 switches

[0109] 51 rectifiers

[0110] 52 Battery

[0111] 53 inverters

[0112] 54 switches

[0113] 55 switches

[0114] 56 charging stations

[0115] 57 switches

[0116] 58 Line

[0117] 59 switches

[0118] 60 line

Claims

A system for generating renewable electrical energy and supplying a plurality of consumers, comprising: a plurality of wind turbines (10, 11) and / or photovoltaic systems (19, 20, 21) as generators of renewable electrical energy, wherein the system is designed to supply a plurality of electric motor-driven or hydrogen-powered vehicles as consumers with electrical energy and / or hydrogen; a plurality of charging stations (33) which are arranged at a distance from one another along a route traveled by the vehicles, wherein the charging stations (33) are suitable for supplying the vehicles with electrical energy and / or hydrogen, wherein the system further comprises a self-sufficient power line network which is electrically connected to the charging stations (33) and which, if necessary,exclusively, with the regenerative electrical energy generated by the wind turbines (10, 11) and / or photovoltaic systems, characterized in that the system according to the invention further comprises at least one transformer station (18) or at least one transformer (31), wherein the system is set up to convert the direct current generated by at least one photovoltaic system (20, 21) and / or the direct current or alternating current generated by at least one wind turbine into a three-phase alternating current in the medium-voltage range and to conduct it in the self-sufficient power line network over a longer distance from beyond the at least one transformer (31) or the at least one transformer station (18) to a charging station (33, 56) as current in the medium-voltage range.System according to claim 1, characterized in that photovoltaic systems and / or wind turbines (10, 11), which are connected to the system's autonomous power grid, are installed near the route, in particular in rows on a shoulder next to a roadway and / or on the central reservation between two roadways. System according to one of claims 1 or 2, characterized in that at least one charging station (33, 56) is arranged in the area of ​​at least one rest stop or parking lot located along the route. System according to one of claims 1 to 3, characterized in that in Area of ​​at least one charging station (33, 56) at least one A power storage device (52) is provided, suitable for storing excess regenerative electrical energy generated in the system. System according to one of claims 1 to 4, characterized in that at least one transformer (46) or a transformer station is arranged in the power path from the generator to the consumer upstream of a charging station (33, 56), by means of which transformer (46) an alternating current in the medium-voltage range can be converted into a three-phase alternating current in the low-voltage range. System according to one of claims 1 to 5, characterized in that a charging station (33, 56) comprises at least one charging column for charging vehicle batteries, wherein preferably at least one further consumer, in the region of the charging station (33, 56) or remote from the charging station, is supplied by the power line network into which the regeneratively generated energy is fed.System according to one of claims 1 to 6, characterized in that in the area of ​​a charging station (33, 56), preferably in the area of ​​a line leading to a charging column or in a charging column, at least one rectifier (51) is provided, configured to convert alternating current supplied by the power line network, preferably alternating current in the low-voltage range, into direct current suitable for charging batteries.System according to one of claims 1 to 7, characterized in that in the power path from the generator, in particular from at least one wind turbine (10, 11), to the consumer, at least one rectifier (34) is arranged, configured to convert the electrical energy generated by the wind turbine (10, 11) into a direct current in the medium voltage range, preferably in a voltage range of at least approximately 800 V to 1200 V, in particular at least approximately 1000 V, wherein the power line network in the power path from the generator to the consumer beyond this rectifier (34) up to preferably the nearest charging station (33) is designed to conduct direct voltage in this medium voltage range. System according to one of the preceding claims, characterized in that it comprises at least one device for the electrolytic production of hydrogen by means of regenerative electrical energy generated in the system, as well as at least one device for storing hydrogen, for example a hydrogen tank or a metal hybrid storage device. System according to one of the preceding claims, characterized in that it comprises means for converting electrolytically produced hydrogen into another energy carrier by chemical reaction, as well as at least one device for storing this other energy carrier in liquid form, optionally under pressure or as a gas, wherein the storage device in particular comprises at least one tank, and the other energy carrier is in particular one or more energy-rich compounds from the group comprising methane, LPG, methanol, ethanol, or ammonia.System according to one of claims 9 or 10, characterized in that it comprises at least one pipeline for transporting hydrogen or the energy carrier from the point of production to a charging station, and the charging station has suitable devices for directly refueling vehicles with appropriately designed drives with hydrogen or the energy carrier. System according to one of claims 9 to 11, characterized in that it comprises at least one suitable device provided in the region of a charging station for converting energy stored in the form of hydrogen or one of the other energy carriers, in the event of excess energy being produced in the system, back into electricity via the device, suitable for supplying electrically powered vehicles with electricity.

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