DE2756636A1 - Solar energy collector producing mechanical energy - heats air to drive turbine-compressor unit having useful mechanical output - Google Patents

Abstract

A solar energy collector (So) contains an absorber (K) with a black surface having a high absorptive capacity and with a low thermal capacity. The absorber is within an air channel (L) and gives up the heat absorbed to the air flowing past it. The heated air passes to a turbine (T) in which it expands adiabatically. It then flows to a compressor (V) which has a cooling jacket so that compression takes place isothermally. The compressed air returns to the solar collector and the cycle is repeated. Part of the energy absorbed by the turbine is used to drive the compressor and the remainder is available as useful work.

Description

Soar power plant

The present invention relates to a thermal power system in which the source of work is not in pressure differences, but in temperature differences.

Heated air from suitable solar collectors is used as the working substance.

Furthermore, heated gases from furnaces or from exhaust gases from (esp.

static) internal combustion engines are used. These gases often arise at ambient pressure. Their use therefore does not require any pressure vessels and heat exchangers. The heated gases can be transferred directly by means of a turbine system be converted into mechanical work. As a lower heat reservoir for uptake The waste heat can be sea water, lake water, fluA water, the ground or the colder Serve ambient air.

In climatically cold zones, the temperature difference between the relatively warm soil or the water (also mine water) compared to the cold outside air can be used to generate mechanical work.

For this purpose, the cold air is heated by the ground or water heat (mine heat) and the waste heat is released into the colder outside air. While using the solar heat is only possible during the day, the use of ground or water heat Can be used all day, but especially at night, because of the temperature differences are usually larger at night than during the day.

In the present case, a solar power plant is described that with heated air from suitable solar collectors at ambient pressure in the cycle is working. So that the efficiency of such a solar power plant is as high as possible the initial temperature at the turbine inlet is to be selected as high as possible. this is achieved by using an absorbent suitable for solar radiation (black) collector materials of particularly low specific heat and at Smallest possible mass, such as, for example, black lacquered aluminum foils or black paper (with the necessary mechanical strength). That Collector material is in a pressure-free, heat-insulated box (the one with a or several well-transparent glass plates or foils are covered) so arranged in the "solar box" that the air slowly flowing through the box opens the bottom and top of the collector material flows past and so the heat withdraws benz. the flowing past Air heats up on him. In order to the air flowing through the solar box, if possible over the entire width of the solar box can be fed in and removed again, the inlet and outlet openings are on on the two sides of the box extended to the entire width of the box. Appropriate Deflection webs ensure an even distribution of the air that is fed in and out (Fig. 1, section A-B).

The heated tuft from the temperature T1 and the ambient pressure PO passes through the compressor as a result of the negative pressure generated (after throwing off outside) into the turbine. Their amount should be V1 m3 and the temperature T1 OC. from Starting from this state 1 (Fig.2), the gas becomes adiabatic at such a low level Pressure P2 relaxes so that it cools down to ambient temperature T. It must however against the higher environment 0 pressure PO work can be done by the area 1-a-2 is shown. After tn 2 the ambient temperature T0 on reversible Ways has been achieved, the gas must be benz. the air from the now low pressure P2 are raised to ambient pressure Po. To do this, the gas from 2 is compressed isothermal to 3, with the compression arms at the constant temperature T with (theoretically) vanishing temperature gradient, d. H.

0 is reversibly released to the environment (where). The higher external pressure PO at the turbine does a work represented by the area 3-a-2 will. Thus, the difference area 1-2-3 represents the one gained and at the same time as a whole highest possible work W.

Because of the low expansion pressure PO, relatively large cylinders and cylinders are required. Turbine volumes are required, but for this they only need to be dimensioned with relatively thin walls. The maximum coagulable work from the hot gases at ambient pressure is given by

Claims (3)

Pat ent claims g solar power plant for the use of solar energy or geothermal directly heated working gas (air) or one with firing or internal combustion engines accumulating heated gas from the pressure level of Environment, characterized in that the heated air BEZW. the heated gas immediately at the pressure level of the environment by means of a turbine compressor system through adiabatic Relaxation and subsequent isothermal compression in mechanical work is implemented. P. Solar power plant according to claim 1, characterized in that one relatively high heating of the air guided in the cycle by a collector material of relatively low specific heat and small mass and with slow and Even air flow in a heat-insulated, pressure-free solar box is achieved. 3. Solar power plant for the use of a heated working gas from the pressure level the environment as described and drawn (further detailed fourth claims Reserved).