Methods and Apparatus for Power Generation

Abstract

A refrigeration apparatus ( 7200 ) includes a heat pump circuit ( 7201 ) and a power generation circuit ( 7100 ). The power generation circuit ( 7100 ) includes an evaporator ( 701 ) including a first and a second heat exchanger ( 710 a, 710 b ), a turbine ( 702 ), a condenser ( 703 ) and a pump ( 704 ). The first heat exchanger ( 710 a ) absorbs heat rejected from the heat pump circuit ( 7201 ) into a power generation circuit ( 7100 ) while the second heat exchanger ( 710 b ) further heats the fluid. The power generation circuit ( 7100 ) includes a bypass ( 707 ) which allows a portion of working liquid to enter the turbine ( 702 ) without passing through the evaporator ( 701 ). A heat pump ( 704 ) with similar bypass is also disclosed. Also disclosed are dual stage turbine design and a nozzle ( 10300 ) for a turbine which includes two fluid paths ( 1011, 1014 ) that adapted to receive and mix the liquid and vapour streams of working fluid, so that the liquid working fluid is vaporized by the heat from the vapour working fluid.

1 .- 32 . (canceled) 
   
   
       33 . (canceled) 
   
   
       34 .- 40 . (canceled) 
   
   
       41 . A heat pump including a first working fluid circuit including, a compressor, a first condenser downstream of the compressor, a first receiver downstream of the first condenser, a throttling valve downstream of the first condenser, and an evaporator downstream of the throttling valve, the heat pump further including heat exchanger means for rejecting heat to a second working fluid cycle, the second working fluid cycle including a boiler, a turbine downstream of the boiler, a second condenser downstream of the turbine, a second receiver downstream of the second condenser and a pump downstream of the second condenser, wherein the heat rejected from the first working fluid cycle preheats the working fluid vapour entering the boiler of the second working fluid cycle. 
   
   
       42 . The heat pump of  claim 41 , wherein the heat exchanger is provided between the first compressor and the first condenser. 
   
   
       43 . The heat pump of  claim 41 , wherein the heat exchanger is provided between the pump and the boiler. 
   
   
       44 . The heat pump of  claim 41 , wherein the turbine is provided with a rotor and a nozzle, the nozzle including a first fluid path which includes a first inlet adapted to receive a first working fluid vapour stream, and a first outlet adapted to communicate a jet of said working fluid to the rotor, the nozzle further including a second fluid path which includes a second inlet adapted to receive a second substantially liquid working fluid stream and a second outlet adapted to communicate a jet of said second working fluid to the rotor, wherein the nozzle is adapted to mix the jets of working fluid so that at least part of the liquid working fluid is vaporized by heat from the working fluid vapour. 
   
   
       45 . The heat pump of  claim 44 , wherein substantially all of the substantially liquid working fluid vapour is vaporized by heat from the substantially vapour working fluid jet before impinging on the rotor. 
   
   
       46 . The heat pump of  claim 44 , wherein the first and second fluid paths are substantially circular or annular in cross-section. 
   
   
       47 . The heat pump of  claim 46 , wherein the second outlet is concentric with the first fluid path. 
   
   
       48 . The heat pump of  claim 44 , wherein the first fluid path has a converging/diverging section adapted to accelerate the stream of working fluid vapour to a mean velocity above the local speed of sound. 
   
   
       49 . The heat pump of  claim 48 , wherein a section of the first fluid path immediately downstream of the converging diverging section has a substantially constant cross-section. 
   
   
       50 . The heat pump of  claim 49 , wherein the second outlet is in the substantially constant cross-section section of the first fluid path. 
   
   
       51 . The heat pump of  claim 41 , wherein the turbine is provided with a generator having a plurality of windings arranged to produce a first alternating current and a second alternating current, a first transformer to increase the voltage of the first alternating current and in the second transformer to increase the voltage of the second alternating current, a first and second rectifying means to rectify the output of each transformer, and the rectified outputs being cumulatively added together to produce a cumulative direct current output, and an inverter means to invert the cumulative direct current output to alternating current electric power. 
   
   
       52 . A method of generating power using a pre-existing refrigeration circuit, the method including inserting a heat exchanger upstream of a condenser in the pre-existing refrigeration circuit whereby heat is transferred from the pre-existing refrigeration circuit to working fluid in a heat pump circuit, the heat pump circuit including an evaporator or boiler downstream of the heat exchanger, a turbine generator downstream of the evaporator or boiler, a condenser downstream of the turbine generator and means to circulate the working fluid about said heat pump circuit.