Solar Power - Electric Generator & Refrigeration Unit

Technical Description

This unit solves the problem of finding an efficient, renewable, cost effective, environmentally safe, long- term solution, to the United States energy needs. By using the solar heat contained in the air, water, ground, by means of vapor technology heat transfer (e.g. heat pump), heat is transferred at a rate greater than the energy required to operate the heat pump. The current rate of heat transfer for a heat pump compressor at 50-degree F. is approximately 12,000 BTU per hour per horsepower. The 12,000 BTUH per horsepower is broken down as follows:

In refrigeration work, three forms of energy must be considered: mechanical, electrical and heat. The electrical energy input to drive the compressor, which compresses the refrigerant, (mechanical), equals 2545. 6 BTU per hour per horsepower. The balance of the 12,000 BTU per hour per horsepower is the heat that is absorbed from the source at the evaporator.

So an approximate breakdown is:

(1 Refrigeration Hp)

1 hp. = 2, 545. 6 BTUH electrical converted into mechanical

+ 9,454. 4 BTUH transferred from the source; e.g. ground, water, air etc.

12, 000 BTUH total heat transferred for each horsepower input.

This total contains the electrical energy input to drive the compressor plus the heat that was absorbed by the evaporator. If we take the combined heat to run a generator it breaks down as follows:

1 hp. = 2,545. 6 BTU

12,000 BTUH divided by 2, 545.6 BTUH = 4.714 hp A ratio of 1:4.714

4.714 hp minus 1 hp needed to drive the compressor = 3.714 hp net gain for every hp input. This of coarse is with 100 % efficiency. So lets assume a more realistic efficiency of 60 %

4.714 hp x 60% = 2.8284 hp - 1 hp needed to drive the compressor = 1.8284 hp net gain

So at 60% efficiency, a 15.0 hp heat pump would supply the equivalent net gain of 27.426 hp for electric generation, (15.0 hp x 1.8284 = 27.426 hp). With today's technology in heat transfer, insulation, and electronics I believe that 75 to 85 % efficiencies are not unrealistic.

27-hp output to run an electric generator 24 hours per day is more than most homes could use.


Heat from the sun heats the air, the ground, water, rain, ocean, etc.... This heat is absorbed in the evaporator coil, #1 as in any standard refrigeration unit. The source of heat can be from an out door air coil, a indoor air conditioning coil, a ground source coil, a water source (lake, pond, well, industrial water etc....), or a refrigerated / freezer space. The refrigerant boils in the evaporator absorbing the heat from the coil and is pulled into the compressor #2. The compressor compresses the gas into a smaller area, concentrating the heat it contains. It is the heat that is absorbed at the evaporator that will provide the energy for the generator, not the compressor. A variable speed fan is used to control the amount of heat absorbed for varying loads and or ambient temperatures at the evaporator on air source evaporators. Compressors are rated according to the amount of heat that they can transfer. The standard with today's technologies is approximately 12,000 BTU's per hour per horsepower input. In other words a 1-hp. motor driving a compressor will transfer 12,000 BTU's per hour from a heat source. Considering the following:

Energy Conversion Equivalents

1 hp. of work = 33, 000 ft. lb. /minute

= 746 watts

=2, 545.6 BTU/hr.

A 1hp compressor rated at 12,000 BTUH transfers the heat equivalent of 4.714 hp.

12,000 BTUH divided by 2545. 6 BTUH per hp. = 4.714

1:4.714 ratio------- 1hp. input to 4.714hp. output

In a normal refrigeration unit this is considered waste heat or heat that is moved from a place where it is not wanted to a place where it is not objectionable. In other words the only work the compressor is doing is to move the heat, not create the heat. That is why a heat pump is such an efficient unit for heating. The heat is derived from various sources, internal heat loads from people, equipment, etc., but the main bulk of heat is from the sum. The sun heats the air, ground water, etc. This waste heat in a standard refrigeration unit after being compressed is blown away from the refrigerant in a condenser. Instead of waste heat, in this unit the heat is pumped into a insulated tank, #3; which holds as much of the heat in as possible and provides a working volume of gas to work with for control purposes. With varying loads, temperatures, etc. this high temperature and high-pressure vapor is then used to power a hermetically sealed generator. The heat that is normally blown into the air is absorbed as energy as the gas expands through the generator drive, #4.

The vapor is then fed through a condenser, which is smaller in size than normal because the bulk of the heat was used to drive the generator. This condenser is used to maintain a pressure drop across the drive unit of 150 psi. and to finish condensing the vapor as needed. Note: Diagram #1, p.4 of unit is not to scale. Also, as in any refrigeration unit, the sizing and matching of components for the most efficient operation is paramount.

The refrigerant is then fed into a receiver and back through a standard expansion valve, #6, to complete the process. Once started the unit would not be stopped except for maintenance, repairs, or breakdowns. The refrigeration compressor might cycle according to load, while the generator would keep going by the volume of gas/heat in the tank #3.

Operation Continued.......

Once started this unit design would continue providing energy to drive the refrigeration unit and produce excess electricity for other uses.

Example: A 1hp refrigeration unit transfers 12,000 BTUH

12,000 BTUH/ 2545.6 BTUH per horsepower = 4.714 hp.

4.714 hp output minus 1hp. to drive the refrigerant unit = 3.714 hp net gain

3.714 hp net gain at only a 30 % efficiency for the generator drive = 1.1142 hp. net gain

3.714 hp net @ 75% efficiency for the generator drive = 2.79 hp net gain

A 10 hp refrigeration \ air conditioning unit would have an output of 27.9 net hp @ 75% efficiency. 10 hp x 2.79 hp @ 75% = 27.9 net hp for electric generation. That is more than enough to power a home with the unit running 24 hours per day. At the very least the unit would provide the electricity to drive just the refrigeration portion. It is my belief that with today's technologies the unit would produce electricity in abundance of what it takes to run the compressor section. This is not a perpetual energy unit. The unit energy is supplied by the heat in the air, which comes from the sun. This unit would work at night, on cloudy days, in the winter, summer, with no external fuels supplied. Think of the possibilities......... Each home, building, car, transportation unit, with its own power supply unit, with refrigeration / air conditioning as a side benefit.

Provided below is the actual performance data from a TRANE split system heat pump.

TRANE Model: TWN030C100A2 outdoor compressor section

Includes the fan, compressor, outdoor coil (evaporator air source), reversing valve, and controls.

The energy efficiency rating for this unit is 7.75 HSPF, Heating Seasonal Performance factor which is based on U.S. Government standard tests of this condenser model. 7.75 HSPF is below the median for heat pump efficiencies.

At an outdoor temperature of 50-degree F the unit has a heat transfer capacity of 28,800 BTUH.

Volts 200 / 230 1 phase 60 Hz

Compressor is rated at 12.0 RLA (run load amps) 2.4 hp Mod. #GP283-EE1-GA

Outdoor fan is rated at .9 FLA. (full load amps) 1/6 hp

Both of the amp ratings are maximum ratings that the unit will operate at. As measured with a 50 degree F outdoor temperature on a brand new unit the compressor RLA was 6.0 amps and the outdoor fan was .4 amps for a total combined amps of 6.4 amps at 238 volts.

28,800 BTUH divided by 2,545.6 BTUH / hp = 11. 314 hp heat transfer output

So for a total hp input of 2.4 hp for the compressor and 1/6 hp, (.1666) for the fan = 2.5666 hp

input & the unit is transferring the equivalent total heat of 11. 314 hp.

11.3 14 hp - 2.5666 hp = 8.747 hp net gain x 75 % efficient = 6.56 hp net gain

And this unit is a low-end efficiency model heat pump.


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