"In the past, big chimneys used to smoke every day in winter. Now, we can't see this situation in our community for four or five years." Li Shifu, a citizen of Harbin in Heilongjiang, China's northernmost Province, who has entered the heating period, said that the reason is that his community has changed to sewage heating instead of traditional boiler heating. Sewage heating sounds incredible, but this technology has been applied and popularized in many parts of China. "We extract heat energy from the sewage in the urban sewage interception trunk canal." Li Jinfeng, head of Jintao Technology Co., Ltd. of Harbin University of technology, said that sewage heating does not lead sewage to residents' homes, but extracts and uses sewage heat energy. There is no need to worry about peculiar smell in radiators. As a specialized and new "little giant" enterprise in China, Jintao Technology Co., Ltd. of Harbin University of technology has been deeply engaged in the field of clean energy for many years, and a number of technologies have been selected into the promotion catalogue of key energy-saving and low-carbon technologies in China. At present, this enterprise has provided sewage heating for more than 80 million square meters of buildings in dozens of cities in China; Compared with the use of coal, the annual emission of pollutants such as carbon dioxide and sulfur dioxide is reduced by more than 4.7 million tons. In northern China, it is cold in winter. Heating is one of the most important livelihood projects. However, the "driven" heating system mainly relying on coal not only consumes a large amount of non renewable energy, but also the haze once became an environmental problem threatening people's health. In recent years, China has accelerated the exploration of clean energy heating in winter to further reduce coal dependence and adverse effects on the atmosphere. In its work report this year, the Chinese government made it clear: "we will strengthen comprehensive air pollution control and joint prevention and control, strengthen the coordinated control of fine particulate matter and ozone, and achieve a clean heating rate of 70% in the north." In order to implement this goal, all parts of China continue to promote "green heating" to take root. Henan Province proposed that 54 million square meters of clean heating capacity such as geothermal energy and biomass energy will be added before November 15. Shandong's goal is to add 56.3487 million square meters of clean heating in cities (counties) and 2.0170 households in rural areas by 2021. At the same time, with the support of a series of policies and measures of the Chinese government, the clean heating industry has developed rapidly. According to incomplete statistics of the clean heating industry committee of China Building Energy Conservation Association, by the end of 2020, there were 8200 clean heating related enterprises in China, with a total output value of 900 billion yuan and more than 1.19 million employees. Entering Baicheng City, Jilin Province, as of July this year, new energy power generation has accounted for more than 60% of the city's total power generation. Liu Yanping, a local citizen, recalled that in the past, there were many small boilers here. As soon as the heating period came, there was a smell of soot in the air. Baicheng Tongye Group invested 3.1 million yuan to build a regenerative electric boiler. Guo Changchun, deputy general manager of the group, said that this electric boiler uses Gudian to store heat. It is heated from 9 p.m. to 7 a.m. the next day to make the temperature in the furnace reach 500 degrees Celsius and heat the whole group during the day. "This has achieved a win-win situation of economic and social benefits." Guo Changchun calculated that after the group adopted the regenerative electric boiler, the annual electricity expenditure was saved by 300000 yuan. In the year of completion, the government awarded a one-time subsidy of 1.1 million yuan, and the cost can be recovered after seven years of use. In southern China, many practices have been carried out in geothermal energy, water source heat pump and industrial waste heat heating according to local conditions. Huaibei City, Anhui Province is an important coal base. By adjusting the energy structure and accelerating energy conservation and consumption reduction, ground source heat pump has become one of the main directions of exploration - in winter, heat in the ground source medium is "absorbed" and heated after increasing the temperature of the circulating medium; In summer, the indoor heat is "absorbed" and released to the ground source medium for storage. Recently, the Zhonghu Mingyue residential community in Huaibei City conducted the commissioning of electric energy instead of ground source heat pump. After opening on November 15, the ground source heat pump will be responsible for the heating of the whole community in winter and even the cooling of next summer. According to the calculation of the power department, only this community can reduce 32000 tons of carbon dioxide emissions, 217 tons of sulfur dioxide emissions, 205 tons of nitrogen oxide emissions and 127 tons of smoke and dust emissions every year. (outlook new era)