Abstract: This paper introduces a new type of air conditioning system that has emerged in foreign countries in recent ten years. This article describes the development and application of water ring heat pump VRV products in foreign countries and related encouragement policies as well as the prospect of promotion in China. And according to the 2005 Beijing "Public Building Energy Efficiency Design Standard" for the equipment part of the overall load factor of performance requirements, its energy-saving discussion. 1. Water ring heat pump VRV application overview Water ring heat pump VRV (water-cooledVRV) is a branch of the VRV series, which based on the air-cooled VRV, the air-cooled (fan + cooler) into a water-cooled Loop + built-in board change) to form a water pipe does not enter the room, but only in the shaft and the host of non-dedicated room; host located in the indoor non-dedicated equipment, body size and weight smaller, can be stacked to place; in use A new type of air conditioning that combines concentration and decentralization. It can be combined with a variety of energy forms and can be applied to all kinds of newly built, renovated or built projects that have existing cold and heat sources or exist inside and outside the area or have both hot and cold demands. Construction scale from a few hundred square meters to several hundred thousand square meters. Host using R410A refrigerant, heat pump and heat recovery type two. One of the concepts of heat recovery, air-cooled VRV has been applied. Using this model, you can achieve the same cooling system in the same cold and heat. 1.1. Development in foreign countries In the late 1980s and early 1990s, Japan's economy was in a period of rapid development. In terms of economic scale, the per capita GNP of Japan in the early 1990s was 29,524 U.S. dollars, ranking the first place in the world, exceeding 20% ​​of the U.S. Various social construction has developed rapidly. It is also from this period that the Japanese government started "implementing the strategy of sustainable development" and "developing the recycling economy and building a recycling-oriented society as an important way and means of achieving a sustainable development strategy." Water-ring heat pump VRV is based on this background, in response to the massive renovation / new projects that emerged at that time resulting from the demand for recycling and sustainable development. After more than a decade of development, the water ring heat pump VRV has achieved rapid development in developed countries such as Japan and Europe and has now developed into the second generation of products. By the end of 2005, the product won the 2005 Japan Energy Conservation Awards - the Energy Conservation President's Award (Note 1) and the European government's incentive tax incentive policy (Note 2). 1.2 Prospects for Domestic Promotion 1.2.1 Sustainable Development of Energy and Environment Since the beginning of the new century, with the start of building a well-off society in an all-round way and the continuous expansion of China's economy, China has become the second largest country after the United States World markets, industrialization and urbanization are accelerating in all aspects. The contradiction between supply and demand of resources and environmental problems also will be aggravated. At the same time of economic development, our country is also the second largest consumer of energy in the world and the second largest emitter of CO2 ("The Necessity of Centralized Air Conditioning Energy Conservation in China"). In 2004, the large-scale power switch-off in various cities in China seriously affected the economic development of the country and the life of ordinary people. Unit GDP, high energy consumption, high cost of the environment has become the primary factor restricting the healthy and sustainable development of our country. The Fifth Plenary Session of the 16th CPC Central Committee proposed that by the end of the "Eleventh Five-year" (2010) China's energy consumption per unit of GDP be reduced by 20% from the end of the "Tenth Five-Year Plan" period. Future National Bureau of Statistics, National Development and Reform Commission on the local economic growth indicators will also be assessed as an important unit of GDP energy content. Experts point out that although the energy consumption in our country is astonishing, there is still a lot of room for energy conservation. As the global economy to the development of information-based emerging industries and people's living comfort requirements continue to increase, more and more energy consumption in the non-traditional industries. In the commercial and service industries, central air conditioning is the main energy-consuming equipment. According to the statistics of Chongqing and Shanghai, central air-conditioning power consumption accounts for 23% and 31.1% of the total electricity consumption of the city respectively. In addition, China's central air-conditioning for civil, public and commercial buildings are generally high energy consumption problems, the general energy consumption of central air conditioning accounts for about 50% of the total building energy consumption, for shopping malls and complex may be as high as 60% . (Based on the above background, in the economic development, energy-saving and new energy development, equal emphasis on the use of renewable energy and advocating the application of environmental protection technologies are of great significance to the sustainable development of our country. Therefore, the water ring heat pump VRV because of its own characteristics, in our country to promote and apply has a very broad market space for development. 1.2.2 Application of water ring heat pump VRV Water ring heat pump VRV design and use there are three main parts: the selection of energy, cooling water pipes and VRV-W. Optimization of the three can make the initial investment and operating costs of the entire system to achieve economic and reasonable. As the water ring heat pump VRV normal working temperature between 15-45 ℃, so it can be used in the types of energy there are three In fact, the water ring heat pump VRV can be used in a wide range of energy forms, as long as they can meet the provision To the water temperature can be between 15-45 ℃. In addition, this air-conditioning system can also be used in combination with conventional ice storage and tank heat storage, which can make use of the design of the cooling water pipelines to a certain extent by referring to the conventional water system design. Water ring heat pump VRV host pressure can reach 1.96MPa. VRV-W design can refer to the selection of air-cooled VRV design. There are several points to note: First, the water pipeline design Ten, a reasonable choice of the location of the shaft, you can make the host as close as possible to the use of space, reducing the refrigerant pipe length loss; Second, the water ring heat pump VRV host plate heat exchanger Small size, more sensitive to dirty plugging and corrosion, it must be closed-loop system, that is, the use of closed cooling towers or open cooling towers + plate change. 2. Introduction of Water Ring Heat Pump VRV in Foreign Countries 2.1 Introduction of New Project Iidabashi The First Building Project is located in Osaka, Japan with a construction area of ​​50,000 square meters. The project is used for office buildings and residential buildings, and has been in operation for 2000 years. The system uses water ring heat pump VRV346 Taiwan (3,086 HP), indoor unit uses 412 (duct). Fresh air with a total heat exchanger 277 Taiwan. The system satisfies the user's need for high-end positioning of the building and roof space as a parking lot and garden. Iidabashi The first building won the Building Construction Association Award. JAL City Hotel project is located in Tokyo, Japan, construction area of ​​5,400 square meters, the use of the hotel, put into service in 1997. The whole system uses water ring heat pump VRV33 units, closed cooling towers 1 (175 tons). The adoption of the system solves the limited problems of the user's roof and the surrounding space and meets the user's need for saving useful space and centralized management. Most of Japan's JAL City Hotel uses a water ring heat pump VRV system. Hilton hotel project is located in Manchester, England, the purpose of the hotel, built in late 2006. The entire building in the room part of the 290 rooms using heat recovery water ring heat pump VRV a total of 29 units. The use of this system meets the local demand for CO2 emission efficiency. 2.2 Reconstruction Project The new building project is located in Osaka, Japan, construction area of ​​80,000 square meters, single-storey building area of ​​over 8,000 square meters, the use of shops, renovation completed in 2004. The entire system uses water ring heat pump VRV139 Taiwan, 700 indoor units, closed cooling towers 2 (330 * 2 tons). Before the transformation, the entire building after years of use, the original air conditioning system has been unable to meet the existing load requirements, but the main equipment such as the host cooling, water circulation pipeline has not reached the age limit; due to different room orientation, location, hot and cold demand Seriously unbalanced. The system to meet the user to use the original cold and heat sources, the lack of supplementary system load, zoning, centralized management and household billing, the ultimate goal is to transform the entire building can not stop operating needs. CLOTHHALLCOURT project is located in the University of the United Kingdom, the building area of ​​3000 square meters, use for college. The whole system uses water ring heat pump VRV12 Taiwan, indoor unit 65. The building is a famous local heritage building, the number two preservation object, the appearance can not be any changes, and the internal space is very limited. The adoption of this system solves the limitations caused by these specific situations while guaranteeing a shorter period and lower running costs for users. 3. Energy-saving analysis of water ring heat pump VRV 1) Refrigeration conditions: As there is no relevant norms in the country can be referred to, only in accordance with Beijing Municipal Construction Committee promulgated in 2005 "public buildings energy-saving design standards" for the steam compression cycle of cold water Heat pump) unit requirements, to do a simple analysis. The table below reflects the COP of the water ring heat pump VRV and a US brand centrifuge and the combined partial load performance factor: IPLV = 2.3% × A + 41.5% × B + 46.1% × C + 10.1% × DA-100% load Coefficient of performance (W / W) Cooling water inlet temperature 30 ℃ B-75% Coefficient of performance at load (W / W) Cooling water inlet temperature 26 ℃ C-50% Water temperature 23 ℃ D-25% Coefficient of performance at load (W / W) Cooling water inlet temperature 19 ℃ It can be seen from the above that the comprehensive partial load performance factor of water ring heat pump VRV is much higher than that of "Standard" (5.1) requirements. Air-cooled VRVs, on the other hand, have a problem of efficiency decay during winter heating due to the low outdoor air temperature (greater than COP1.8) and are completely absent from the water-ring heat pump VRVs. If IPLV is used as an indicator of its operating economy, the power consumption of each load factor will be substituted into the corresponding positions of A, B, C and D, which can reflect the power consumption to a certain extent. 2) heating conditions: the above analysis is the cooling conditions. In the winter heating operation, its energy-saving due to the different energy allocation and use of different ways, there are a variety of situations: According to whether there are internal and external areas to consider: 1. There are internal and external areas: By transferring heat from the inner area to the outer area, the heat source can be saved. 2. No partition inside and outside: the system assumes the entire construction