The existing heating and cooling system of some hospital was reconstructed adopting the air-conditioning technology with multiple water sources,a patent technology,and deep aquifer energy storage technology,and utilizing geothermal energy and low enthalpy heat energy in lake water.After the reconstruction,the utilization rate of geothermal energy has been increased from 50.9% to 94.5%,in the running of the system,the discharge of wastes decreases largely,so the cost of treatment of urban environment pollution is saved,and the ecological environment is protected effectively,resulting in good environmental and social benefits.