【 Weak current College 】 ice storage air conditioning system and application---Power By 【 China power house network 】

1, ice storage air conditioning system principles and main characteristics of ice storage air conditioning technology means electricity trough with ice and temporary storage in ice devices exist, as needed (such as peak) to chill-out for use. This can be achieved on the grid "peak load shifting," which helps to reduce power installed capacity, to maintain safe and efficient operation of the power grid. Ice storage air conditioning system has the following main features: (1) to reduce the cost of running the air conditioning system. (2) the capacity of the refrigerating unit is less than conventional air conditioning systems, air conditioning system for the cooling towers, pumps, transmission and distribution system capacity reduction. (3) in some conventional air-conditioning systems with a cool device that can increase 30% to 50% of the cooling capacity. (4) can serve as a stable improves cold source supply, air conditioning system operating reliability. (5) refrigeration equipment are at full load of health, reduce the number of open, extended equipment downtime. (6) on the power grid for peak load shifting, raise to the power grid operation stability, economy, lower power generation capacity. (7) the reduction of environmental pollution from power plants. 2 system components and ice classification 2.1 system way ice storage air conditioning system typically consists of refrigeration units, thermal storage equipment (or water), auxiliary equipment and devices connected, adjust control. Ice storage air conditioning system design for a variety of species, either form, its ultimate purpose is to provide the buildings with a comfortable environment. In addition, the system should also achieve energy savings with efficiency, optimal functioning electricity provides users with a secure and reliable ice storage air conditioning system. 2.2 ice way classification according to how the ice, ice can be divided into static ice, dynamic ice two categories. Thereare also some special ice-ice, the ice itself remains relatively inactive, this kind of ice including ice coil, encapsulating and other specific forms. Dynamic ice in the ice during the ice crystals, ice slurry, and is in motion. Each of these ice-specific form has its own characteristics and is suitable for the occasion. 3 run policy and automatic control strategies and General running 3.1 air conditioning systems, thermal storage system with refrigerant unit or storage device, or both for building cooling to determine at any given moment, how much load is provided by the refrigeration unit, the load is supplied by the storage device, that is, the method for the system's operation strategy. Thermal storage system in the design process must develop a suitable running strategy, identify specific control strategies, and detailed to give the device is in the system should be regulated or cyclical start stop. For some cool system operation strategy mainly resolved each period refrigeration equipment between cooling load allocation issues, the following is a cool system typically select several operation strategy. 3.1.1 refrigeration units preferred thermal storage system with refrigerant unit priority run policy refers to the refrigeration unit first direct cooling, more than the refrigeration unit cooling capacity of load from storage devices with the release of cold. This strategy is often used for unit cooling storage charges higher than the required amount of units, refrigeration units producing cold energy costs through reduced air conditioning peak load values can significantly save system investment costs. 3.1.2 cool device priority cool device priority run policy is the release of cool device priority over cold, cold load of release from the refrigeration unit is responsible for the cooling. This method is typically used for unit cool content costs less than the unit amount of production cold refrigeration unit. Cool device priority in control than refrigerationunits priority relatively complex. In the next cool process before you begin, cool devices should, as far as possible, the storage of cold finished, that is, all release takes full advantage of cool devices that may use storage capacity, reduce storage system running costs; in addition you should avoid cool device in the release process for some time ago most of the energy saving chill-release and later peak load, refrigeration units and storage device does not meet the needs of the phenomena of air conditioning load and should therefore be reasonably control cool equipment remaining cooling capacity, especially for design, air conditioner peak load appear in the afternoon sessions are very important. In General, cool device priority run policies require cool system should predict the day 24-hour air conditioning load distribution map, and determine the date of the refrigeration unit in the cooling process minimum cooling volume control distribution map to ensure cool device at any time have sufficient explanation of the cooling capacity with refrigeration units meet the requirements of air conditioning load. 3.1.3 load control-(restricted load type) load control type is less than the load times, refrigerating units of cooling capacity limits of a control method. Typically this method is affected by the power load limit is used, over refrigeration units for cooling capacity of load can be cool devices. For example, a city power load peak hours (8: 00 ~ 11: 00), the prohibition of the refrigeration unit is running. 3.1.4 balanced load-balanced load type is defined as part of the cool system, refrigerating units in design day 24 hours basically full load operation; in the night filled with cool during the day when refrigeration units producing cooling capacity greater than air-conditioning cooling load, will meet the cooling load of the remaining cold (ice form)-aside; when air-conditioning cooling load is greater than the amount of refrigeration refrigeration unit,not the cool devices (melt). This way the system of minimum initial investment, refrigeration units for maximum utilization, but design, air-conditioning load peak periods and local power load peak hours are the same, that is, with the local price lows periods overlap, if not overlap, the system of higher operating costs. 3.2 automatically control cool system of control, in addition to ensuring that cool and cooling mode conversion and air conditioning supply or return water temperature control, largely resolved refrigeration units and storage devices for cooling load allocation problems, especially in part load, should ensure, as far as possible, be cool device cold finished, you can use free-run policy priority, even with all the cool running, that is, the closure of the daytime refrigeration units, all of air conditioning load from storage devices meet. In the design, when air conditioning load should be used in refrigeration units priority run policy to ensure hourly air conditioning load requirements. Currently cool system of automatic control systems, most of the computer technology of direct digital controllers and electronic sensors and actuators combine directAdd digital control system. Refrigeration units for cool content is output, and the quantification of cool device of cold is the total amount of output. If the votes are in-line, the control system can make it easier to find, easy to maintain a constant water temperature; and for parallel system, water supply temperature control more difficult, especially in the interpretation of the late cold-melt, cool device outlet temperature gradually rise, and exports as compared to the refrigeration unit is very difficult to keep the temperature constant. In order to make the daily cold cool device, keep fully release more constant water temperature to meet design requirements on air-conditioning load, typically using computers as a thermal storage system with monitoring equipment; and using the system settingsof the flow meter, thermometer feedback signal, hourly monitor internal ice equipment; computer-to-air system load forecasts to develop cool system policy is a refrigeration unit priority or cool device priority. 4, engineering analysis, energy-saving technology to run services to municipal electricity hospital ice storage air conditioning system for direct and cool comparison test runs, results are as follows: 4.1 municipal electric power company announced daily peak, ping, Valley electric electrical electricity price peak time: 8: 00 ~ 11: 00 and 18: 00 ~ 23: 00, the price is $ 0.878/kWh; Ping: 7: 00 ~ 8: 00 and 11: 00 ~ 18: 00, the price is $ 0.540/kWh; Valley electric: 23: 00 ~ 7: 00 the following day, the price is $ 0.224/kWh. 4.2 benefit analysis ** ** project completed in 1999, and put into use, the air conditioning is about 5700m2, cool system selection 2 screw dual operating refrigeration units, stand-alone refrigeration capacity air-conditioning operation 70RT (246kW), ice condition cooling capacity 47RT (165kW). Cool system consists of a 60m3 ice tank, built-in STL-CO-hockey, 3 desk solution pumps, cooling water system, automatic control system. Cool refrigerant for ethylene glycol (25%) — — the aqueous solution.
Test results are as follows: (1) ice time, thermal storage capacity: cool-time 7 hours (late 11: 00 ~ 6: 00 a.m. time) all Valley electric time. Storage capacity: 1702.66kWh. (2) of the first cycle, which is cool — release cold operating mode. Total electricity consumption, electricity together 1234.81kWh 420.33 element for a chilling 1676.94kWh. (3) of the second cycle, i.e. direct cooling operation mode. Total electricity consumption, electricity together 1159.78kWh 792.63 element for a cold water 1342.78kWh. (4) the first cycle ways and second-cycle electricity consumption increase compared:, but electricity saving 75.03kWh 372.3 Yuan/day.
5. promote the recommendations
Ice storage air conditioning system for the application of places: shopping malls, hotels, restaurants, office buildings, cold load peak and peak, the site of long duration; gymnasium, exhibition hall, cinema, etc. larger cooling load, a place, a short time; pharmaceutical, food processing, brewery, dairy industry, with a cooling capacity of air conditioning load large, the majority concentrated in the manufacturing sector during the day; the existing air conditioning system with cooling capacity cannot meet the load requirements, need to expand the amount of space for cooling, this time can not increase the host, transformed into ice storage air conditioning system is most advantageous. Ice storage air conditioning excellent energy-saving environmental benefits, the technology used for decades, is already very mature and reliable. The author of introducing ice storage air conditioning makes the following recommendation: publicity, universal ice storage air conditioning system-related knowledge; the electricity sector and the construction sector joint promotion pilot demonstration project; the Government established a special support funds, lending to encourage enterprises to adopt ice storage technology. On this basis, the Government in formulating policies that force the application of ice storage air conditioning.
Small information
China will implement the four energy-saving policy in China to speed up the building conservation-oriented society, the national authorities will take four energy policy to ensure the smooth implementation of the ambitious goals. 1, through the adjustment of industrial structure to promote energy saving. To change the mode of growth of China as an economic development strategic focus, strictly control the energy-intensive, high supplies, energy intensive aquaculture development, and environmental carrying capacity under resources, optimize, implement a regional industrial layout optimization development, focusing on development, restrictions on the development and exploitation of different policies. 2, through the perfect price and tax system to promote energy saving. China will continue to give full play to the market allocation of resources and the basic role, accelerate resource prices of market development, establish reflect scarcity of price formation mechanism and the establishment of sound fiscal policies related to accelerate the development of the system, to encourage the production and use of energy-saving products, including low fuel consumption, small vehicles and tax policies. 3. by increasing the level of science and technology to promote energy saving. China will continue to encourage technical innovation and tax policies, strengthening the introduction of energy technologies for digestion, absorption and then innovation, promoting innovation in government procurement, the implementing intellectual property strategies and technology standards strategy, the implementation of the promotion of innovation and entrepreneurship of monetary policy, the accelerated energy high-tech industrialization and generalization of advanced technology. 4, through the strengthening of management to promote energy saving. It will step up the formulation and revision of promotion resources and effective use of laws and regulations, establish strict high consumption, high-polluting industry access standards that accelerate the development of product standards mandatory performance efficiency, revise and improve major energy-consuming industries, energy-saving design specifications, building energy efficiency standards established as soon as possible.