SOLAR ENERGY HIRE SYSTEM AND METHOD FOR FLIGHT OPERATING AREAS

Description

[0001] The invention relates to a solar energy utilization system for airfields with the features of claim 1 and a solar energy utilization method with the features of claim 7.

[0002] Operating airports is energy-intensive, as large spaces in terminals and other facilities require heating and cooling. Therefore, providing energy-efficient airport equipment is a key objective. One such system is known from US Patent A 4,132,074.

[0003] The problem is solved by a solar energy utilization system with the features of claim 1.

[0004] This concerns a solar energy utilization system for airport aprons. Airport aprons are characterized by a solid surface, usually made of concrete. These aprons must meet certain minimum requirements worldwide, particularly regarding thickness and load-bearing capacity. In any case, large areas, and therefore large masses of concrete, are exposed to solar radiation.

[0005] Within the framework of the solar energy utilization system, a heat source device serves to extract thermal energy induced by solar radiation from the material or material composite of the airfield surface.

[0006] The heat recovered from the airfield surfaces can be further processed by at least one additional device, and different devices can also be combined with each other.

[0007] For example, at least one heat storage device serves to temporarily store heat energy.

[0008] At least one heating device can be used, for example, to heat at least one building, in particular an airport building.

[0009] Cooling can be provided by means of a cooling device, for example, using an absorption chiller in conjunction with a heat pump. This makes it possible, for instance, to convert solar heat into cooling energy for an airport building. Since the cooling demand is generally highest when solar radiation is also strong, this combination allows for the thermally efficient, time-synchronized operation of an airport system.

[0010] The heat energy can also be used in at least one power generation device.

[0011] At least one heat pump device can be used to increase the temperature of the thermal energy obtained from the heat source device. This temperature increase enhances the usability of the heat.

[0012] The use of the heat source device makes a previously unused area of ​​the airfield – and thus a very large mass – accessible for thermal analysis. Since only certain temperature values ​​can be achieved through solar radiation, more thermally valuable energy can be generated with the help of at least one heat pump device, which can then be made available for further use.

[0013] According to the invention, the heat source device comprises a pipe system, in particular a capillary pipe system, wherein a water-glycol mixture is used as the heat medium flowing in the pipe system during operation. Such pipe systems are easy to install and require relatively little maintenance.

[0014] In one embodiment, the pipe system of the heat source device extends through at least a portion of the runway surface, particularly in a meandering pattern. Meandering here means that, for example, a pipe changes its direction at certain intervals—usually in a regular pattern—in order to systematically traverse an area of ​​the runway surface. Several pipes can also be arranged in a meandering pattern to cover the area. The pipes of the pipe system can have a diameter between 2 and 10 cm and / or, in sections where they are arranged parallel to each other, the pipes have a spacing of between 5 and 100 cm, particularly between 5 and 20 cm. According to the invention, the pipes of the pipe system are arranged on average between 5 and 15 cm below the surface of the runway surface. Often, a layer-centered arrangement of the pipe system within the concrete slab of the runway surface will be advantageous.

[0015] In a further embodiment, the heat storage device comprises at least one sensible heat storage medium, in particular a solid absorber, at least one latent heat storage medium, and / or at least one thermochemical heat storage medium. In one embodiment, water can be used in a sensible heat storage medium and / or in a latent heat storage device, in particular an ice storage medium.

[0016] Furthermore, in one embodiment, the at least one heat pump device comprises a compression heat pump, an absorption heat pump or an adsorption heat pump.

[0017] In order to efficiently utilize solar radiation on the airfield, the airfield, as the apron, has, according to the invention, at least partially a reflection-reducing coating or paint to increase heat absorption, especially for shortwave radiation and a reflectance of less than 25% for concrete.

[0018] According to the invention, the material or material composite of the airfield surface is concrete, wherein the thickness of the airfield surface, from which the heat source device extracts thermal energy, is between 20 cm and 80 cm, in particular between 30 and 40 cm.

[0019] In one embodiment of the solar energy utilization system, the at least one heat storage device can also supply heat energy, at least partially, to a local or district heating network.

[0020] The problem is also solved by a solar energy utilization method with the features of claim 7. As embodiments, heat storage devices or cooling devices can be used, each in conjunction with a heat pump device.

[0021] Exemplary embodiments of the solar energy utilization system and the solar energy utilization method are described with reference to the following figures. These figures show Fig. 1 a schematic representation of an airport with runways; Fig. 2 a schematic representation of the principle of an embodiment of a solar energy utilization device; Fig. 3 a schematic representation of a first embodiment of the solar energy utilization device and the solar energy utilization method for an runway; Fig. 4 a schematic representation of a second embodiment of the solar energy utilization device and the solar energy utilization method for an runway; Fig. 5 a schematic sectional view through an runway.

[0022] In Fig. 1 A schematic top view shows an airport with an airport building 20. The aircraft 21 move on operational areas 10, such as taxiways, aprons (including ramps), runways, landing strips, or open areas.

[0023] Typically, runway surfaces are covered with a concrete surface, with the concrete-covered area at airports ranging from 10⁵ to 10⁶ m². These runway surfaces are exposed to direct or diffuse solar radiation, causing them to heat up during the day. Temperatures on these surfaces can exceed 60°C.

[0024] The amount of energy radiated on average over the year depends, among other things, on the geographical location of the airport.

[0025] The area-specific solar radiation is largely constant up to the atmosphere (1,368 W / m²). However, atmospheric reflection, scattering, and absorption reduce the radiation received at the Earth's surface. For Berlin (52° north latitude), the average irradiance is 125 W / m². Global radiation, as the average annual total, ranges in Germany from 900 kWh / m² on the coast to 1,200 kWh / m² in southern Germany. In regions around the equator, global radiation reaches up to 2,500 kWh / m², meaning it is more than twice as high as in Germany.

[0026] The large areas of the airport operating areas 10 and the relevant solar radiation S on the airport operating areas 10 thus introduce considerable amounts of thermal energy into the material. This thermal energy can be utilized with the embodiments of a solar energy utilization system or a solar energy utilization process described below.

[0027] In a top view, in Fig. 2 A pipe system 4 is shown as a heat source device within an airfield 10. The pipe system 4 here comprises a single, meandering polyethylene pipe. The meandering arrangement is designed as a kind of serpentine pattern, meaning the pipe changes direction at regular intervals, with longer sections of the pipe lying parallel to each other. Other pipe layouts are also possible in principle.

[0028] The airfield 10 is heated by solar radiation S.

[0029] The pipe system 4 is traversed by a water-glycol mixture (e.g., 61% water - 39% glycol) as a heat transfer medium. Due to solar radiation S, the heat transfer medium heats up within the material (or material composite) of the airfield surface 10.

[0030] The heated heat medium can then be used with a variety of different devices.

[0031] In Fig. 2 The principle is shown according to which the heat medium at least one heat storage device 3 for the temporary storage of heat energy, at least one heating device 31 for heating at least one building, in particular an airport building, at least one cooling device 32, at least one power generation device 33 and / or at least one heat pump device 2.

[0032] The devices mentioned here are generally not used individually. In the Fig. 3 and 4 Some possible combinations are shown as examples, wherein the part of the heat source device is combined with the pipe system 4 of the embodiment according to Fig. 2 This corresponds to the relevant description.

[0033] In the embodiment according to Fig. 3The heat medium is supplied to a heat pump device 2 to raise its temperature, as the initial temperature of the heat medium from the airfield 10 is relatively low. This temperature increase enhances the usable value of the heat energy, which is achieved through an external energy input Q. After the heat energy has been transferred to the heat pump device 2, the heat medium is pumped back to the pipe system 4 of the airfield 10 via a pump 5.

[0034] The now relatively hot heat medium is then used to operate an absorption heat exchanger as a cooling device 32. The cooling energy generated can be used to air-condition an airport building 20. This would take advantage of the fact that the required cooling capacity is generally high when solar radiation is high. No heat storage would be needed, since the thermal processes of heating and cooling occur synchronously.

[0035] In Fig. 4 Another embodiment is shown. The thermal energy provided by the heat pump device 2 is not consumed immediately. It is transferred from the heat pump device 2 to at least one thermal storage device 3 for temporary storage of the thermal energy. The thermal storage device 3 can then release the thermal energy to a consumer at a predetermined time. One possible use is the supply of heat to the airport building 20 for heating purposes.

[0036] A heat storage device 3 is an energy technology device which has the following three processes: charging, storing and discharging.

[0037] In a sensible heat storage device 3 for thermal energy, a sensible change in the temperature of the heat storage device 3 occurs. A storage medium is heated or cooled. The amount of stored energy depends on the specific heat capacity of the material. Since the temperature differences between the storage medium and the environment are generally greater in sensible heat storage devices 3 than in other storage types, thermal insulation plays a crucial role. Because water has a high specific heat capacity and offers further advantages such as good environmental compatibility, high availability, and low cost, many sensible heat storage devices are operated with water. Alternatively, sand, gravel, rock (e.g., granite), concrete, bricks, iron, thermal oil, a gravel-water mixture, molten salt, or sodium can also be used.

[0038] In connection with airfield operating areas 10, a portion of the airfield operating area 10 can be used as a heat storage device 3 with concrete as the storage medium. This is possible due to the large quantities of concrete already present.

[0039] In latent heat storage devices 3, the energy required for a phase change is stored in addition to sensible heat. In practice, the solid-liquid phase transition is typically used. Phase change media such as water, salt hydrates, salts, salt mixtures, paraffin, fatty acids, sugar alcohols, or PEG can be used.

[0040] An ice storage system is one possibility for a latent heat storage device 3. It utilizes the high crystallization energy released during the phase transition from 0°C water to 0°C ice. This energy is sufficient to heat water from 0°C to 80°C. Such a volume can, for example, be arranged below the heat source device 1, i.e., the concrete of the airfield surface 10.

[0041] In a thermochemical heat storage device 3, chemically reversible reactions (e.g., using silica gels or metal hydrides) are employed, in which the reaction products can be separated and stored for extended periods. Due to the separation, no storage losses occur. Only during discharge does the exothermic reaction release the stored energy. Thermochemical energy storage devices allow for very high energy storage densities.

[0042] In principle, it is possible to combine several and even different heat storage devices 3 with each other. It is also possible to couple the heat storage device 3 of the solar energy utilization system for airfields 10 with a solar cell system.

[0043] An energy balance calculation for a solar energy utilization system for an airfield area 10 with an area of ​​10,000 m² in Berlin or a comparable geographical location yields, for example, an energy of 3,263 MWh in one year.

[0044] The thermal properties of the material of the flight operating surfaces 10 (e.g. concrete) are influenced by the material parameters thermal conductivity, heat capacity, thermal diffusivity (i.e. ratio of thermal conductivity and heat capacity) and / or the reflection coefficient.

[0045] The thermal conductivity of concrete depends on the degree of hydration, the moisture content, the aggregate, the pore type and the pore content.

[0046] In one embodiment, a concrete C35 / 45 (E=34,000 N / mm², Poisson's ratio = 0.15, thermal conductivity 2.3 W / mK, specific heat capacity 1,000 J / kgK, density 2,300 kg / m³) with a thickness of 40 cm is used. For a typical airfield area of ​​300,000 m², this results in a concrete volume of 120,000 m³ with a mass of 276,000 t.

[0047] In Fig. 5 Figure 1 shows a cross-sectional view through an airfield 10, in which three cutaway pipes of the pipe system 4 are shown. The mean distance a between two of the meandering pipes (see Figure 1) is shown. Fig. 2 The distance is 15 cm. The pipes of pipe system 4 are laid in one plane here. It is also possible, in principle, for the pipes to be laid at least partially in different planes.

[0048] According to the invention, the pipes are laid approximately 5 to 15 cm below the surface, i.e., roughly in the middle of the layers.

[0049] The pipes are in the embodiment according to Fig. 5 The pipes are laid at equidistant intervals, which is not mandatory. It is possible to adapt the pipe arrangement to the structural and / or thermal requirements. Reference symbol list

[0050] 1 Heat source device 2 Heat pump device 3 Heat storage device 4 Pipe system 5 Pump 10 Airfield operating area of ​​an airport 20 Airport building 21 Airplane 31 Heating device 32 Cooling device 33 Power generating device average distance between pipes Q Heat input SS Solar radiation

Claims

1. A solar energy utilization system for flight operation areas (10), namely aprons of an airport, comprising a heat source device (1) for extracting thermal energy induced by solar radiation from the material or material composite of an apron (10) and at least one heat storage device (3) for the temporary storage of thermal energy, at least one heating device (31) for heating at least one building, in particular an airport building, at least one cooling device (32), at least one power generating device (33) and / or at least one heat pump device (2) for increasing the temperature of the thermal energy obtained with the heat source device (1), and wherein the heat source device (1) includes a tube system, in particular a capillary tube system, wherein a water / glycol mixture is used in operation as the heat medium flowing in the tube system, the tubes (4) of the tube system being arranged on average between 5 and 15 cm below the surface of the apron (10), and wherein the material or material composite of the apron (10) includes concrete, wherein the thickness of the apron (10), from which the heat source device (1) extracts thermal energy, is between 20 cm and 80 cm, in particular between 30 and 40 cm, and to increase the heat absorption of the apron (10) at least partially includes a reflection-reducing coating or paint, in particular for short-wave radiation and a degree of reflection of less than 25% for concrete.

2. The solar energy utilization system according to claim 1, characterized in that the tube system (4) of the heat source device (1) passes through at least part of the apron (10), in particular in a meandering manner, wherein the tubes of the tube system have a diameter of between 2 and 10 cm and / or the tube or tubes (4) of the tube system arranged in a meandering manner have a spacing of between 5 and 100 cm, in particular between 5 and 20 cm, in sections in which they are arranged parallel to each other.

3. The solar energy utilization system according to at least one of the preceding claims, characterized in that the at least one heat storage device (3) includes at least one sensible heat reservoir, in particular a solid absorber, at least one latent heat reservoir and / or at least one thermochemical heat reservoir.

4. The solar energy utilization system according to claim 3, characterized in that water is used in a sensible heat reservoir and / or in a latent heat storage device (3), in particular an ice storage device.

5. The solar energy utilization system according to at least one of the preceding claims, characterized in that the at least one heat pump device (2) includes a compression heat pump, an absorption heat pump or an adsorption heat pump.

6. The solar energy utilization system according to at least one of the preceding claims, characterized in that the at least one heat storage device (3) delivers thermal energy at least partially to a local or district heating network.

7. A solar energy utilization method for flight operation areas (10), namely aprons, wherein a heat source device (1) extracts thermal energy induced by solar radiation from the material or material composite of the apron (10), and subsequently at least a storage in a heat storage device (3) for the temporary storage of thermal energy, a heating device (31) for heating at least one building, in particular an airport building is operated, a cooling device (32) is operated, a power generating device (33) is operated and / or a heat pump device (2) is operated for increasing the temperature of the thermal energy obtained with the heat source device (1), and wherein the heat source device (1) includes a tube system, in particular a capillary tube system, wherein a water / glycol mixture is used in operation as the heat medium flowing in the tube system, the tubes (4) of the tube system being arranged on average between 5 and 15 cm below the surface of the apron (10), and the material or the material composite of the apron (10) includes concrete, wherein the thickness of the apron, from which the heat source device (1) extracts thermal energy, is between 20 cm and 80 cm, in particular between 30 and 40 cm, and to increase the heat absorption of the flight operation area (10) at least partially has a reflection-reducing coating or paint, in particular for short-wave radiation and a degree of reflection of less than 25% for concrete.

8. The solar energy utilization method according to claim 7, characterized in that the temperature level of the extracted thermal energy is raised with a heat pump device (2) and the thermal energy at the raised temperature level is supplied to at least one heat storage device (3) for the temporary storage of the thermal energy.

9. The solar energy utilization method according to claim 7, characterized in that the temperature level of the extracted thermal energy is raised with a heat pump device (2) and the thermal energy is supplied to a cooling device (32), in particular to an absorption heat device.