The work principles and characteristics of four thermal power generation approaches which are suitable to low grate energy are presented

including the organic Rankine circulation(ORC)

Kalina cycle

temperature differential power generation and thermoacoustic power generation.The effects of organic Rankine circulation fluids on performance of the power generation system and conversion efficiency of the thermoacoustic power generation system are analyzed.A great prospect for the comprehensive application of solar energy is pointed out after discussion of the features and drawbacks of those power generation approaches.The efficient utilization scheme for solar cell waste heat is proposed

namely the organic Rankine circulation system combing photovoltaic power generation with thermal generation.The two phase booster device in this system can convert the solar cell's waste heat into power output of the hydraulic turbine

thus to realize energy conversion from solar energy to electric energy.A higher application efficiency of solar energy is expected.