The research of heat pump technology in China began in 1950s, and the Institute of Thermal Energy of Tianjin University carried out the earliest heat pump research in China. The article "Heat Pump and Its Application in China" written by Professor Lu Canren from 65438 to 0956 is the earliest existing research document on heat pump in China.

In 1960s, China began to apply and develop heat pumps in the field of HVAC, and achieved a lot. 1960 Professor Wu Shenyi of Tongji University published "Introduction to Heat Pump Heating and Suggestions for Jinan to Try Heat Pump Heating"; 1963 The former East China Architectural Design Institute and Shanghai Air Conditioning Factory began to develop heat pump air conditioners. 1965 Shanghai refrigerator factory has successfully developed the first CKT-3A heat pump window air conditioner with a heating capacity of 3720W in China. 1965 Tianjin University and Tianjin Air Conditioning Factory developed the first underground water source heat pump air conditioning unit in China; 1966 cooperated with Sifang Vehicle Research Institute of the Ministry of Railways to carry out the air/air heat pump test of trunk passenger cars; 1965 according to the heat pump theory, the research team led by Professor Xu Bangyu and Professor Wu of Harbin Institute of Architecture and Engineering put forward a new technology of using auxiliary condenser as the secondary heater of constant temperature and humidity air conditioning unit for the first time, which is the first time in the world. 1966, together with Harbin air-conditioning machinery factory, we started to develop a new type of constant temperature wet heat pump air conditioner which uses the residual heat of refrigeration system as the secondary heating of air conditioner.

From 1978 to 1988, the application and development of heat pumps in China have entered a comprehensive recovery stage. During this period, in order to fully understand the current situation and progress of heat pump development abroad, a large number of related works have been published, domestic publications have actively published heat pump translations, tested and analyzed foreign heat pump products, and actively participated in international academic exchanges. At the same time, some well-known foreign heat pump manufacturers began to invest and build factories in China. For example, American Carrier Company was one of the first foreign companies to invest in China, and took the lead in establishing a joint venture company in Shanghai on 1987.

During the period from1989 to1999, China heat pump ushered in a new development milestone. The forms of heat pumps used in China began to diversify, including air/air hot gas, air/water heat pump, water/air heat pump and water/water heat pump. During this period, there were no fewer than 300 state-owned, private, wholly-owned and Taiwan-funded air-conditioning production enterprises in China, gradually forming a complete heat pump air-conditioning industrial system in China. Water-loop heat pump air conditioning system is widely used in China. According to statistics, by 1999, there were about 100 projects in China, and 20,000 groundwater heat pump units were in operation. In the early 1990s, a large number of air source heat pump cold and hot water units were produced. In the mid-1990 s, a well groundwater heat pump cold and hot water unit was developed; In the late 1990s, sewage and groundwater heat pump systems began to appear. The research of soil coupled heat pump has become a hot spot in the field of HVAC in China. The domestic research direction and content mainly focus on the underground heat exchanger, which is an innovation based on foreign technology.

After entering the 2 1 century, due to the rapid development of urbanization in China and the growth of GDP per capita, the air-conditioning market in China has been promoted, and the application of heat pumps in China has become more and more extensive. The development of heat pump is very rapid, and the research of heat pump technology is also constantly innovating. From 2000 to 2003, the application and research of heat pump were unprecedentedly active and achieved fruitful results.

During the four years from 2000 to 2003, the total number of patents was 287, with an average of 7 1.75, which was 4.9 times that of 1.989 ~ 1.999. From 2000 to 2003, there were *** 1 19 invention patents, with an average of 29.75, which was 4.25 times of the average of 1989 ~ 1999 invention patents.

From 2000 to 2003, the number of heat pump literature increased sharply, for example, the number of literature in 2003 was five times that of 1999. There are 105 graduate students majoring in heat pump technology in colleges and universities across the country, with an average of 26.25 students per year, which is more than seven times the average level in the 1990s.

Almost all provinces and cities in China have engineering examples of applying heat pump technology. The research of heat pump technology is more active, and innovative achievements emerge one after another. In just a few years, there are three innovative achievements: the same well recharge heat pump system, the integrated system of soil cold storage and soil coupled heat pump, and the single-stage and two-stage coupled heat pump system for cold regions.

2. Application foundation and practical research of ground source heat pump.

The research on ground source heat pump in China began in 1980s. At first, some universities and scientific research institutions made special research on the related technologies of ground source heat pump. Table 3- 1 lists some research projects.

Table 3- 1 Some research topics of ground source heat pump in colleges and universities

The research work mainly focuses on the following aspects: (1) heat transfer model and heat transfer research of underground heat exchanger; Numerical simulation of transient operating conditions in summer: theoretical and practical research on simulation model of heat pump devices and components;

Study on refrigerant substitution of ground source heat pump air conditioning system: joint application of solar energy, hydropower and other energy sources with ground source; Design and construction of ground source heat pump system: study on economic performance and operation characteristics of ground source heat pump system: technology and practice of groundwater heat pump recharge: experimental study on soil thermal properties and thermal conductivity.

Numerical simulation and experimental study on groundwater transportation by groundwater heat pump with groundwater recharge in the same well: basic research on application of integrated system of soil cold storage and ground source heat pump.

In 1990s, Professor Ding from Beijing University of Technology and Professor Fang from Shandong Institute of Civil Engineering and Architecture successively studied and investigated the ground source heat pump technology in Oklahoma State University and Sweden, Germany and Canada. After returning home, they put themselves into the practice of domestic ground source heat pump technology research. Professor Ding presided over the major scientific research project "Research on Cascade Utilization Technology of Low Temperature Geothermal Energy" in Beijing, and studied the deep utilization technology of geothermal energy in the school through three stages: small test, pilot test and engineering, creating a precedent in China. Professor Fang's key scientific and technological research project "Key Technology of Geothermal Comprehensive Utilization" in Shandong Province was rated as "reaching the international leading level" in expert appraisal.

At the same time, the former universities such as chongqing jianzhu university, Tongji University, Hunan University and Qingdao Institute of Civil Engineering and Architecture established the experimental system of soil-coupled heat pump and carried out comprehensive research, and the research of soil-coupled heat pump quickly became one of the hot research topics.

After entering the 2 1 century, with the support of the national natural science foundation, the research of ground source heat pump is more in-depth and innovative. On the basis of fully understanding the development and application of ground-source heat pump and ice storage technology at home and abroad, Professor Yao Yang of Harbin Institute of Technology transformed the traditional technology with new technology, integrated and integrated the technical elements and achievements of ground-source heat pump and ice storage, and put forward a brand-new air conditioning system, that is, the integrated system of ground-source heat pump and ground-source heat pump, which is suitable for air conditioning load and heating load. The Institute of Heat Pump Air Conditioning Technology of Harbin Institute of Technology has successively established a mathematical model of groundwater recharge and groundwater heat pump transportation in the same well. The analytical solution of groundwater seepage in a single homogeneous aquifer under the conditions of constant flow in the same well and groundwater recharge is derived. The temperature field of groundwater aquifer of groundwater source heat pump with recharging in the same well is numerically simulated. In addition, the field practice research of groundwater source heat pump project with the same well recharge was carried out with Beijing Hengyuan Technology Development Co., Ltd. ..

On the basis of research work in colleges and universities, the research results are continuously applied to engineering practice. For example, the school of urban construction and environmental engineering of Chongqing University has adopted the ground source heat pump system in the small office building in Miquan City, Xinjiang and the HVAC experimental building in Zone B of Chongqing University. Major scientific research projects with a heating (cooling) area of over 5000m2, such as the newly-built comprehensive science and technology building, Shaw Library, the rebuilt School of Economics and Management, the indoor geothermal swimming pool and the newly-built teaching building which can accommodate 8,000 students. The academic lecture hall project of Shandong University of Civil Engineering and Architecture (including 500m2 academic lecture hall, 2700m2 student study room and air conditioning area of computer room) selects two water-water heat pump cold and hot water units. Outdoor geothermal heat exchanger is a ground source heat pump system composed of 25 groups of parallel vertical U-shaped buried pipes.

In order to popularize the research results, colleges and universities have embarked on the road of combining Industry-University-Research. 1999 Research and Design Institute was established by Geothermal Center of Tianjin University and Tianjin Ganquan Group Company. In 2000, Shandong Jianzhu University established the first ground source heat pump research institute, which was specialized in theoretical research, technical development, engineering design and rotary engineering guidance of ground source heat pump heating and air conditioning system. Beijing University of Technology established Beijing Tiandi Liu Neng Technology Development Co., Ltd., and Beijing Qingyuan Century Technology Co., Ltd. in Tsinghua University also participated in the engineering practice of ground source heat pump. Moreover, many enterprises are also closely integrated with scientific research institutions in universities, relying on the technical strength of universities to establish scientific research institutions, develop products and undertake projects. Such as Tsinghua University and Shandong Fuleda Air Conditioning Equipment Co., Ltd., Tongji University and Guangzhou Conghua Zhongyu Air Conditioning Technology Development Co., Ltd., Shandong Institute of Civil Engineering and Architecture and Beijing Jiahe Ye Sheng Groundwater Heat Pump Air Conditioning Co., Ltd., Yantai Renyuan Air Conditioning Equipment Co., Ltd., Shandong Lihong Air Conditioning Equipment Co., Ltd., Beijing University of Technology and Shandong Mo Lifeng Company, Hubei Fengshen Purification Air Conditioning Equipment Engineering Co., Ltd. and Huazhong University of Science and Technology, Southeast University, etc.

3. Relevant management regulations and policies of ground source heat pump in Beijing.

1) groundwater heat pump

In recent years, with the construction of a "resource-saving, environment-friendly" society and the realization of the national goal of energy conservation and emission reduction, various localities have also introduced projects to support the development and utilization of shallow geothermal energy. For example, on May 3, 20061,the Beijing Municipal Development and Reform Commission, together with the Municipal Water Affairs Bureau and the Land and Resources Bureau, jointly issued a document to subsidize the heating and cooling projects using the underground groundwater heat pump system according to the standards of 35 yuan /m2.

Because the underground water source heat pump project must pump and recharge groundwater, before the underground water source heat pump project starts, it is necessary to demonstrate the water resources of the construction project, prepare a water resources demonstration report, and analyze the feasibility, rationality, protection measures and influence on other water users in accordance with the requirements of the Management Measures for Self-use Water Resources Demonstration of Construction Projects issued by the Ministry of Water Resources.

In order to protect valuable groundwater resources and avoid the adverse effects of blindly starting the groundwater heat pump on the existing centralized water supply sources and adverse geological environment consequences (such as cross-contamination of groundwater, ground subsidence, ground fissures, etc.). ), local water authorities have also formulated targeted management measures according to local hydrogeological conditions, such as the pumping and irrigation distance of groundwater heat pumps in the Notice on Strengthening the Management of Groundwater Heat Pumps in Our City issued by Beijing Water Affairs Bureau on May 16, 2007.

(1) The aquifer pumped by the groundwater heat pump system is Quaternary water, and the well depth shall not exceed100m;

(2) The distance between the pumping well and the building is not less than 30m；; The horizontal spacing of pumping wells shall not be less than 50m, and the spacing of pumping wells shall not be less than100m;

(3) In order to prevent water pollution caused by water exchange between different aquifers and ensure the recharge effect, pumping and irrigation must be carried out in the same aquifer;

(four) it is strictly prohibited to approve the construction of groundwater heat pump system in underground water source protection areas, land subsidence areas, serious over-exploitation of groundwater and confined aquifers in waterworks;

(5) The construction of underground water heat pump pumping and irrigation wells shall strictly abide by the relevant national regulations and norms to ensure the quality of pumping and irrigation wells. Units undertaking sinking construction shall have corresponding qualifications;

(6) The pumping wells of the newly-built groundwater heat pump system shall be equipped with metering devices for pumping and recharging. The built groundwater heat pump system must also install metering facilities within a time limit;

(7) The monthly quarterly report system shall be implemented for the pumping capacity of groundwater heat pump. Users of groundwater heat pump system shall report the pumping quantity and reinjection quantity of the current month in writing at the end of each month.

2) Ground source heat pump

Because ground source heat pump does not need to exploit groundwater, its impact on geological environment is much lower than that of groundwater ground source heat pump, and its potential geological risk and safety risk are also much lower than that of groundwater ground source heat pump, but the initial investment of ground source heat pump is slightly higher than that of groundwater heat pump project. Therefore, on May 3rd, 2006, the Beijing Municipal Development and Reform Commission, together with the Municipal Water Affairs Bureau and the Bureau of Land and Resources, issued a document to subsidize the heating and cooling projects using the ground source heat pump system according to the standard of 50 yuan /m2, which is higher than the groundwater ground source heat pump subsidy (35 yuan /m2).

According to the Notice of Beijing Municipal Bureau of Land and Resources on the Application of Ground Source Heat Pump Project, the project construction unit is required to submit the Report on Exploration and Evaluation of Shallow Geothermal Energy of Ground Source Heat Pump System, which has passed the expert review. The main contents of the report are as follows: preface: briefly introduce and explain the source and requirements of the task; Briefly comment on the previous hydrogeological work degree and the present situation of shallow geothermal utilization in exploration area; Describe the stratigraphic distribution, climatic conditions and hydrological characteristics in this area; Briefly describe the process of exploration work and the completed workload. Preliminary design scheme of ground source heat pump system; Demonstration of hydrogeological conditions of the project location; Exploration work; Evaluation of shallow geothermal energy where the project is located: test of formation heat transfer capacity; This paper discusses the calculation basis of shallow geothermal energy utilization, and calculates and evaluates shallow geothermal energy. According to the principle of resource protection and rational development, this paper puts forward the corresponding utilization mode, briefly describes its guarantee degree, predicts its possible changing trend, and comprehensively evaluates the shallow geothermal energy resources. Conclusions and recommendations.

The "Implementation Opinions on the Construction and Application of Ground Source Heat Pump System" issued by Shenyang clearly pointed out that the ground source heat pump system is a new energy utilization technology that uses shallow geothermal energy for heating and cooling, and has the characteristics of cleanliness, high efficiency and energy saving. Promoting the construction of ground source heat pump system is conducive to optimizing energy structure, promoting energy complementarity and improving energy utilization efficiency. It is required that in the core area of 455km2 within the Third Ring Road in Shenyang, buildings within 409km2 that meet the application of groundwater heat pump technology should be planned and built in principle.

4. Academic exchanges related to ground source heat pump.

In recent years, the academic flow of ground source heat pump has gradually warmed up. There are more and more conferences to discuss the development and application of ground source heat pump from the perspectives of geothermal application, heat pump technology development and clean energy utilization.

1978-2005, the second professional committee of China Refrigeration Society hosted 12 national academic conference on waste heat refrigeration and heat pump technology. 1988 Guangzhou institute of energy, Chinese academy of sciences hosted an expert seminar on the application and development of heat pumps in China. Since the 1990s, the HVAC Committee of China Architectural Society and China Refrigeration Society have specially added "heat pump" to the annual national HVAC academic conference. 1994 On September 6th, the Geothermal Professional Committee of China Energy Research Association held the 4th National Symposium on Geothermal Energy Development and Utilization.

From June, 2000 to September, 23, 2000, the Department of High-tech Development and Industrialization of the Ministry of Science and Technology held the "Sino-US Ground Source Heat Pump Technology Exchange Conference" in Beijing. The conference introduced the ground source heat pump technology, its application abroad and its popularization in China. The theme of the conference is "using ground source heat pump technology to provide energy-saving solutions for heating and cooling in residential quarters or public buildings, greatly reducing temperature and operating costs".

On the morning of May 20th, 2002, the seventh session of the International Energy Agency (IEA) was held in Beijing International Convention Center, which was the first time that IEA held such a meeting in China and non-governmental organization member countries. The purpose of this conference is to promote the exchange and application of heat pump technology in the world, especially in China. Fulda, a leading domestic enterprise, became the sole sponsor.

On March 17, 2003, the Institute of Ground Source Heat Pump of Shandong Institute of Architecture and Engineering and the Thermal Professional Committee of Shandong Institute of Architecture and Engineering jointly held the "International Report on New Technologies of Ground Source Heat Pump" in Shandong Institute of Architecture and Engineering.

In order to carry out the concepts of "high-tech Olympics" and "green Olympics" and provide practical clean energy construction schemes for Olympic venues, the seminar on clean energy construction schemes for venue projects organized by the magazine of Engineering Construction and Design of Beijing University of Technology was held in Beijing from July 6 to 8, 2004. Experts at home and abroad were invited to discuss the possible application of ground source heat pump technology in the clean energy construction scheme of stadiums and gymnasiums, so as to provide a basis for the final determination of the energy scheme of stadiums and gymnasiums in 2008 Olympic Games. The meeting was attended by BOCOG, Beijing Municipal Development and Reform Commission, Beijing Municipal Science and Technology Commission and other relevant units, academic and design authorities at home and abroad, as well as representatives of 28 Olympic venues owners and related enterprises.

In September 2005, the 39th Council of the International Geothermal Association was held in Beijing. Mr Lund, the chairman and director attending the meeting, was invited to participate in the national seminar on sustainable development of geothermal industry.

On September 23rd, 2005, the China Clean Energy Action Promotion Meeting was held in Beijing, which was jointly organized by the representative office of the United Nations Development Programme in China, the Ministry of Science and Technology and the State Environmental Protection Administration. Representatives from more than 40 cities in China, including mayors and environmental protection directors, attended the meeting. The purpose of the meeting is to promote the achievements and experience of the four-year project "Capacity Building for Reducing Urban Air Pollution by Using Clean Energy and Clean Energy Technology" jointly established by the United Nations Development Programme, the Ministry of Science and Technology and the State Environmental Protection Administration.

On June 27th, 2007, 65438, the shallow geothermal energy research and extension center of China Geological Survey was established, and the center was located in Beijing Bureau of Geology and Mineral Exploration and Development. The center specializes in the research and promotion of shallow geothermal energy in China. On June 29 ~ 30, 2007, an on-site experience exchange meeting on the development and utilization of geothermal energy (shallow geothermal energy) hosted by the Ministry of Land and Resources and undertaken by Beijing Bureau of Land and Resources and Beijing Bureau of Geology and Mineral Exploration and Development was held in Beijing Friendship Hotel. More than 400 representatives from all over the country inspected the demonstration project and fully exchanged views on the exploration and evaluation, development and utilization of shallow geothermal energy resources at home and abroad, the present situation and development prospect of heat pump utilization, examples of shallow geothermal energy utilization, policies and technical regulations. The meeting called on geological technicians to carry out in-depth basic research on the occurrence, source and migration law of shallow geothermal energy resources, laying a solid foundation for the country's large-scale scientific and rational development and utilization of shallow geothermal energy resources. The meeting published the Proceedings of the National Field Experience Exchange Meeting on Geothermal (Shallow Geothermal Energy) Development and Utilization.

From June 5 to February, 2007, the national advanced seminar on the development and utilization of shallow geothermal energy resources organized by the Research and Extension Center of China Geological Survey was held in Beijing. Many experts and scholars in the development and utilization of shallow geothermal energy resources introduced the theory, core technology and practical experience of shallow geothermal energy resources from exploration and evaluation to development and utilization in detail from both theory and practice. The meeting encouraged the scientific and rational development and utilization of shallow geothermal energy resources, and made contributions to the realization of national energy conservation and emission reduction targets.

With the increasing number of meetings and exchanges, publications related to ground source heat pumps are also coming out. 65438-0988 The textbook Heat Pump edited by Professor Xu Bangyu was published by China Building Industry Press. The Principle and Application of Heat Pump edited by Professor Yu was published by Machinery Industry Press 1993, and the Technology and Application of Air Heat Pump edited by Professor Jiang Nengzhao was published by Machinery Industry Press 1997. 1994 Zheng Zuyi's Design and Innovation of Heat Pump Air Conditioning System was published by Huazhong University of Science and Technology Press. 1998 published the application of Dr. Zheng Zuyi's heat pump technology in air conditioning.

In 200 1 year, the book "Technical Guide of Ground Source Heat Pump Engineering" translated by Xu Wei et al. of Air Conditioning Institute of China Institute of Building Research was published, which provided a reference for domestic ground source heat pump engineering designers and constructors. The Technical Guide for Ground Source Heat Pump Engineering was originally a professional book on ground source heat pump technology published by the ASHRAE Society of the United States, and was supported by seven units including the US Department of Energy, the US Department of Defense and the Canadian Department of Natural Resources. This book is divided into principle, design, installation and energy saving. The contents include: introducing the classification, working principle, system composition and comparison with conventional systems of ground source heat pump system; How to carry out on-site geological investigation and experiment; Design of geothermal heat exchanger, groundwater heat exchanger and surface water heat exchanger system; Design of power transmission and distribution system and indoor air conditioning system; Installation, debugging and testing of ground source heat pump system; Energy-saving measures and energy-saving design calculation of ground source heat pump system, and provide characteristic data of geotechnical, antifreeze, plastic pipe and fittings.

In 2004, the design of water-loop heat pump air conditioning system written by Professor Ma Zuiliang of Harbin Institute of Technology was published, which is a monograph that comprehensively expounds the theoretical basis and practice of the application of water-loop heat pump air conditioning system. The book summarizes the name of renewable energy water-loop heat pump air conditioning system for the first time. This concept will inject new vitality into the water-loop heat pump system and make its application more extensive, reasonable and economical. Therefore, this renewable energy water-loop heat pump system has a good application prospect and has a long-term strategic significance for solving the energy and environmental problems of HVAC.

The publication of these textbooks, works and translations has promoted the popularization and popularization of heat pump air conditioning technology in China.

At the same time, the number of papers on ground source heat pump technology in domestic scientific and technological journals has also increased significantly. Magazines such as HVAC, Refrigeration and Air Conditioning all set up special topics for discussion. Therefore, Engineering Construction and Design magazine published a special issue of ground source heat pump, and conducted a survey on the application of ground source heat pump in China. In 2004, the fourth issue of Investigation Report on the Application of Ground Source Heat Pump in China showed the application of ground source heat pump in China for the first time. Building Science and Technology magazine reported the ground source heat pump technology of Hi-Tech Group Co., Ltd. and Shandong Fulda Air Conditioning Equipment Co., Ltd. for many times.