Changzhi, an important traditional energy base in China, is currently undergoing a revolution, with solar energy becoming the preferred energy source for household bathing and heating without winter in the boilers ... More and more green energy technologies are entering the city's production life . Recently, a new courtyard near the North Outer Ring Road, a new technology for environmental protection and energy saving is playing a magical role in several offices here. An air-conditioning system consisting of several tubes with black insulation and a cabinet about 1 meter high, with the control button pressed, the breeze slowly blew through the compartment window at the top of the room. What is surprising is that these cold winds are not "produced" by traditional refrigeration technology but are collected from more than a dozen meters underground. This technology is called energy-saving ground-source heat pump technology. This technology through the use of groundwater or low energy in the soil as a source of cold and heat, after energy conversion to achieve the winter heating and cooling purposes in summer. The central air-conditioning system supported by this technology is eco-friendly, energy-saving and investment-saving. It is the most economical energy-saving central air-conditioning system in the world. It is understood that the application of the technology in our city has just started, at present this new technology has begun to be promoted and applied in the city with the support and encouragement of the environmental protection department. Some residential quarters and offices have begun to install this kind of utilization of energy Refrigeration and heating air conditioning system.