Weak current College】 【ground source heat pump system (1) --- Power By】 【China power house network.

I. concepts
Ground source heat pump is a shallow underground geothermal resources (also called to be, including underground water, soil or surface water, etc.) both heating and cooling energy efficient air conditioning system. Ground source heat pump by entering a small number of high-quality energy (e.g. electricity), the realization of low-temperature heat energy to heat-transfer. Geothermal energy in the winter as a heat pump heating source of heat and cold sources of air conditioning in summer, in winter, the ground can take the heat "in the" out to raise the temperature, the supply of indoor heating; in summer, the indoor thermal out down to the release. Usually ground source heat pumps consume energy, 1kW users can get more than heat 4kW or cold. And boiler (electricity, fuel) heating systems, boiler heating can be more than 90% of the power or 70 ~ 90% of the fuel energy to heat, for users to use ground-source heat pump than electric boiler heating savings of more than two thirds of the energy savings than fuel boiler of about half of the energy; because of the heat pump's heat temperature year-round more stable, generally 10 to 25 degrees centigrade, refrigeration, heating coefficient 3.5 ~ 4.4, and compared with traditional air-source heat pump, up to 40% of its operating expenses for General conditioning of 50-60%. Therefore, in the last decade, especially in the last five years, ground-source heat pump system in North America such as the United States, Canada and Switzerland and the Nordic as, Sweden and other countries made a rapid development, China's ground-source heat pump market are becoming increasingly active, you can expect that this technology will become the 21st century most effective heating and cooling and air conditioning technology.
Second, the recent development of domestic and international ground source heat pump
Ground source heat pump you can follow the history of SCHOTT to 1912 a patent, Switzerland and ground source heat pump real business applications are nearly ten years of history. Such as the United States, as of 1985 National 14,000 Mesa heat pump, which is installed in 1997 45,000 units installed so far, but the 400,000 annually to 10 per cent of the rate steady growth. In 1998 the United States commercial building ground source heat pump system has accounted for the total population of air conditioners 19%, with new buildings account for 30 per cent. United States ground source heat pump industry was established by the United States Department of energy, environmental protection Department, love Madison power Research Institute and many other ground-source heat pump manufacturers formed United States ground source heat pump Association, the Association in recent years will be invested US $ 100 million in the development, research and extension work. United States plan to achieve annual 2001 40 million Mesa heat pump is installed, it will reduce greenhouse gas emissions 1 million tons, equivalent to a reduction of half a million car emissions or kind of tree-planting 1 million acres, the annual saving energy costs up to $ 4.2, thereafter, the annual energy costs increase 1.7 billion. And the United States in the development of different ground-source heat pump, Central, and Northern Europe such as Sweden, Switzerland, Austria, Germany and other countries mainly use shallow geothermal resources, underground soil buried pipes (depth < 400 m deep) of ground source heat pump, used to indoor floor heating and providing hot water. According to a 1999 statistics for household heating appliances, the proportion of ground source heat pumps, Switzerland is 96%, 38%, Austria as a 27 per cent in Denmark. United States particularly optimistic about China's market, United States Department of energy and the Ministry of science and technology in November 1997, signed the Sino-u.s. energy efficiency and renewable energy cooperation protocol, which is one of the main content of the "heat pump", the project is intended to be used in China, Beijing, Hangzhou and Guangzhou 3 cities with the building of a geothermal heat pump for heating and air conditioning business architecture to promote the use of such "green technology", alleviate China coal and oil dependence, so as to achieve the aim of diversification of energy resources. Currently, the three ground-source heat pump demonstration project is being implemented, has entered the stage of implementation. At the same time, the Chinese Ministry of science and technology enterprise Corporation commissioned brewing the United States of ground source heat pump technology and equipment for the introduction of the Chinese market, which will promote the commercialization of ground source heat pumps, industrial development, and make our research and development of ground source heat pumps as soon as possible to keep pace with international trends. China heat pump industry in recent years are beginning to start, but development momentum. Tianjin University, Tsinghua University partnerships with relevant Enterprise Learning Consortium developed the Chinese brand of ground source heat pump system, has completed a number of demonstration projects, a growing number of Chinese users begin to familiarize yourself with the heat pump and application became interested in, you can expect the Chinese ground source heat pump market prospects. The reason for China's ground-source heat pump market Outlook optimistic, partly to save conventional energy, make full use of renewable energy in the domestic and international trends; on the other hand, China has good heat-pump based on scientific research and application, as early as the 1950s, Tianjin University of heat energy Institute Professor Lu-Chan on our earliest heat pump, 1965, developed the first water-cooled heat pump air conditioner. Chongqing jianzhu University, Tianjin University of units on the underground coil heat pump has also carried out many years of research. Guangzhou Institute of the Chinese Academy of Sciences and other units also repeatedly held nationwide for heat pump technology development and application of thematic seminars. We have reason to believe that, while fully learn foreign advanced technology and operations experience, based on strong support at all levels of Government, China's technology sector and the business community work together to rely on its own strength is fully capable of a short time develop with Chinese characteristics of ground source heat pump industry.
3. ground-source heat pump characteristics
1. in the case of renewable energy technology
Ground source heat pump is the use of the Earth's surface and shallow geothermal resources (usually less than 400 metres deep) and heat source for energy conversion of heating and air conditioning systems. Ground shallow geothermal resources can be called to be (EarthEnergy) refers to the surface soil, groundwater or rivers and lakes in the absorption of solar energy, geothermal energy and low-temperature heat energy reserves. Surface layer is a huge solar collector, a collection of 47 per cent of the amount of solar energy per year than the human use of energy more than 500 times. It is not affected by geography, resources limited, the real amount of large broadcasting, is everywhere. This kind of storage on the surface of the shallow near infinite, and renewable energy can also be clean renewable energy.
2. in the case of cost-effective and energy-saving technologyOperation
To be or the surface temperature of shallow geothermal resources are relatively stable, year round than the ambient air temperature in winter, in summer than ambient air temperature is low, is a very good air conditioning with heat pump, heat and cold sources, this kind of temperature characteristics make ground source heat pump than the traditional air conditioning system is more efficient to run 40%, so you want to save energy and save operating costs 40%. In addition, to be relatively constant temperature characteristics, allowing the heat pump unit operation more reliable and stable, but also ensures that the system's efficiency and economy. According to the United States Environmental Protection Agency EPA estimates, design and install good ground source heat pump, on average, you can save users 30-40 per cent of the running of the heating refrigeration and air conditioning.
3. environmental benefits significantly
Ground source heat pump of pollutant emissions, compared with air-source heat pump, equivalent to a reduction of 40 per cent, compared with electrical heating, equivalent to 70 per cent of the reduction, if combined with other energy-saving measures in energy conservation and emission reduction would be more obvious. Although the use of refrigerant, but less than conventional air conditioning unit 25 per cent of the filling quantity; in the case of self-contained system that the device can be put on the factory floor in advance, sealed refrigerant leakage rate greatly reduced. The device runs no pollution, you can build in residential areas, there is no burning, no smoke, no waste, no need to dump fuel waste site, and no long distance transmission of heat.
4, multi-purpose a machine, a wide range of applications
Ground source heat pump system for heating, air conditioning, also for hot water supply, multi-purpose a machine, a system can replace the original boiler plus air conditioning of two sets of equipment or system; can be applied to hotels, shopping malls, office buildings, schools and other buildings, more suitable for Villa residential heating and air conditioning. In addition, the unit for long service life, are in 15 years; the unit is compact, space saving; low maintenance; a high degree of automatic control, unattended. Of course, like any thing, ground source heat pump is not perfect, if its application are subject to different regions, different users and national energy policies, the impact of fuel prices; one-time investment and running costs as users vary; the use of groundwater use, will be subject to the constraints of local groundwater resources, ground source heat pump does not require the use of groundwater, groundwater recharge, all will not produce pollution on water quality.
IV. principles and classification
1. heat pump operating principle
As natural as the water from flowing low, from high-temperature heat always flows cold. However, people can create machine, like the water from low to high and water pumps, a heat pump can take the heat from the aspiration to high temperature and low temperature. So the heat pump is essentially a heat lifting equipment, its own consumption of energy, the environment part of the media storage energy to mining, increase utilization warm bits, and the entire heat pump unit consumes power of only one-third of the heating rate or lower, it is also energy-saving characteristics of the heat pump.

Heat pump and cooling principle and system equipment composition and function is the same, the vapour compression heat pumps (refrigeration) system is mainly composed of compressor, evaporator, condenser and throttle:
Compressor: plays a compression and transmission cycle refrigerants from low temperature and low pressure, to the role of high temperature and high pressure service, is a heat pump (refrigeration) system of the heart;
Evaporator: is the output of the equipment cooling capacity, its role is to enable the flow of refrigerant liquid throttle in evaporative cooling, to absorb heat, reach of refrigeration;
Condenser: is an output device, the heat from the evaporator heat absorption together with compressor consumption power the transformation of heat in the condenser cooling medium away, achieves the purpose;
Expansion valve or throttle: on the circulation of blood to throttle and regulation enters the evaporator of the circulation of refrigerant flow.
According to the second law of thermodynamics, compressor consumes power (power) to compensate for the cycle of continuous heat absorption from the low-temperature environment, and to high heat, and reciprocating and circulation.
Classification 2, heat pump
The heat pump is the need to heat, condenser, evaporator heat from the environment, the heat from the environment is called heat; on the contrary refrigeration is needed the cold evaporator, condenser heat to the environment, in which case the heat to the environment of objects known as cold source. Evaporator under Recycle refrigerants and environmental heat transfer media, mainly divided into water-air heat exchangers and heat transfer in two forms. This heat pump or refrigerator under and environmental heat transfer media, can be divided into water-water, water-air-, air-water, and air-air-a total of four categories. Use air for cooling and heat pump, called air-source heat pump. Air-source heat pump has a long history, and its installation and use are very easy, wider application. But because of the difference in air temperature, in typical application area is South of the Yangtze River. In North, winter average temperature below zero degrees Celsius, air-source heat pumps run not only the poor, poor stability, but also because of frost problem, and inefficient. Use water for cooling of thermal water source heat pump, call it. Water is an excellent source of heat, the heat capacity, heat transfer performance, and generally water-source heat pump cooling and heating efficiency or capacity higher than the air-source heat pumps, but because of the water source, water source heat pump applications far and air-source heat pump.
5. heat pump operating principle
Ground source heat pump water source heat pump is the use of a form, it is the use of water and geothermal energy (water, soil or surface waters) and heat exchange as a water source heat pump and heat source, the winter and can take the heat "in the" out of the supply of indoor heating, this time to be able to "heat"; summer room heat out, release to surface water or groundwater, soil, then to be able to "cold sources".

Ground source heat pump for heating and air conditioning system is mainly divided into three parts: outdoor geothermal energy and heat transfer systems, water source heat pump unit and indoor heating air conditioning Terminal system. One of the main water source heat pump machine has two forms: water-water or water-air-type. Three systems rely on the water or air thermal heat transfer media delivery, water source heat pump and geothermal energy to heat transfer media between water, and building heating and air conditioning at the end of the heat transfer medium can be air or water.
Ground source heat pumps compared with air-source heat pump,Many advantages:
Annual temperature fluctuations. Winter temperature than the air temperature in summer than air temperature is low, ground-source heat pump for heating and refrigerating factor than air-source heat pump, can usually be higher than 40%, so you can save energy and cost savings of around 40%.
Winter run without defrosting, reduces the satisfaction of cream and defrosting.
To source a better energy storage function.