In winter heating in northern China, there are problems such as "taking coal as the boiler" and "boiler emissions of pollutants". The amount of coal burning is large, and the emissions of pollutants are mainly sulfur dioxide and soot. With the acceleration of urbanization in the northern region, technological upgrading of industrial enterprises and the transformation of coal-fired heating mode, the clean energy heating mode has been increasingly promoted in the northern region.

The heat pump is a kind of green energy with high efficiency, energy conservation and clean environmental protection. It is a kind of equipment that takes the low and middle energy in the air as the main heating and cooling energy. In recent years, with the continuous maturity and improvement of heat pump technology, heat pump heating has developed rapidly.

According to the data provided by the Heating Branch of China Building Energy Conservation Association, the heating effect of heat pump units has reached more than 80% in the urban pipe network heating projects in Beijing, Shanghai, Guangzhou, Shenzhen and other places. Therefore, the economic analysis of low-temperature heating in the north can provide technical support for heating equipment in the south.

Based on the research and analysis of the practical application of STS low-temperature air source heat pump under the background of the "coal to electricity" project of clean heating in winter in northern China, this paper analyzes and compares the cost of the air source heat pump heating system under different operating conditions, in order to achieve the purpose of reducing the investment recovery period and operating costs of the project.

Taking a thermal operation project in Beijing as an example, for civil energy-saving buildings (including residential and public buildings), the design load is 40W/m2, and the load factor is 0.66. The total heating hours in the heating season is 2880, and the total heat demand per square meter per quarter is 76.03kWh (273715kJ). The STS low-temperature air source heat pump unit is used for heating. The operating cost per unit area in the heating season is 14.8 yuan/m2/heating season, and the operating cost per unit area of coal-fired boiler is 16.9 yuan/m2 under the same conditions.

In northern cities, air-source heat pump has the advantages of energy saving and efficiency increasing, and its main application is heating. It is the most economical, effective and convenient method to use air source heat pump when the winter temperature is below 20 ℃ in most areas of the north.