Overview of Cogeneration in China

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1 Overview of Cogeneration in China Hua Xinglu Xiao Zenghong Meng Shuai Li Yang Shenyang institute of Engineering, Shenyang; China Abstract: The development of cogeneration is the effective measures to saving energy and protecting the environment. CHP career has become an important industry in China with the efficient use of national resources and further improvement of relevant laws and regulations. The article discussed and summarized from basic introduction of cogeneration, status quo of cogeneration and difficulties encountered during development of cogeneration in China. On this proposes We put forward to the policy recommendations to promote development of cogeneration rapidly and healthy, analysis the trend of cogeneration in China finally. Keywords: China; cogeneration; discussion and summary 1. Introduction Energy, environment and development are the three themes faced mankind today. Rational development and utilization of energy will impact on the environmental protection and sustainable development of mankind directly. The using of energy not only promotes all human activities, but also promotes the development of society and economy. It is the driving force of economic development. Now most of countries attach great importance to production and consumption of energy. Per capital consumption of energy has become one of the indicators to measure a country s degree of modernization and progress. On the tradition aspects of using for energy to see, there are some inadequate, such as serious pollution and waste, ineffectiveness and other deficiencies. The proposed and implemented cogeneration can overcome shortcomings of traditional energy resources. The cogeneration is the joint production of heat and power. It can be available commercial implementation currently and is the highest technology that can achieve the large-scale energy conversion efficiency. CHP compared with thermoelectric of production, it has some advantages of reducing energy consumption, improving environmental quality, improving the heating quality, facilitating utilization, improving the urban landscape and so on. Our government advocates and encourages the development of cogeneration business explicitly. 2. Introduction of cogeneration Cogeneration is defined a production which combined heat and power in the same plants. CHP uses abandoned heat in ordinary plants to proving cheap heat for 1

2 industry and domestic. The heat source for the outside is adjustment extraction from extraction turbine or exhaust from back-pressure turbine. Due to no the cold source loss, The efficiency of cogeneration can be increased to 85%, is much higher than the large condensing unit (thermal efficiency is up to 40% in general). CHP improves fuel efficiency, is an important energy-saving measures. The power plant that run in cogeneration way is thermal power plant. The part of heat in Power plant will be delivered to every household by heat pipes during generation process. So when burning the same amount and quality of coal, thermal power plants can not only provide electricity, but also provide industrial steam production and hot water for residential heating. In addition, due to the big boiler capacity, dust effect, realize desulfurization and denitrification in the furnace. The thermal power plant s environmental and social benefit is relatively larger than the small boiler thermal power plants. Compared with the power plant, the thermal power plant has a lot of advantages. (1) to reduce energy consumption; (2) to improve air quality; (3) conservation of urban land; (4) to improve the heating quality; (5) ease of utilization; (6) to improve the city s image; From the analysis above, cogeneration brought significant economic and environmental benefits, solved the problem of energy re-use highly. It is worth large scale use. 3. The status of cogeneration of our country Our coal-fired cogeneration power plant has begun construction in the late 1950s early 1960s. The main power plant are Wuhan Qingshan power plant, Luoyang power plant, Fulaerji power plant which reconstructed by the former Soviet Union. From 1953 to 1967, the installed capacity of thermal power plant units that more than 6MW are about 20 percent of the power units. In the ten years of chaos stage, the capacity of our country s cogeneration dropped significantly, to 1500MW,accounting for only 5.8 percent of thermal power installed capacity, End up to 2005, the installed capacity of cogeneration units that more than 6MW is up to about MW. In the recent years, the cogeneration industry in China developed rapidly. The year growth rate of installed capacity is about 20% percent since 2006 in four years, two years at around 15 percent, outstanding achievements. From 2005 to 2012, annual increased installed capacity of thermal power plants are 13.3 million to million kilowatts, and its growth rate is the highest in the world. The country s total capacity of heating units reached million kwh in the end of 2007, up to 120 million kwh 2

3 in the end of The installed capacity of thermal power plants are account for approximately 19 percent of the country s power plants, the capacity of heating units are 14 percent of country s total capacity of units, in the world s highest. By the end of 2010, the capacity of CHP units are million kwh, accounting for percent of the same installed capacity of power plant units, accounting for 17.3 of the total capacity of units. According to the latest data show that by he end of 2012, the installed capacity of CHP which is 6000 kilowatts or much more had already exceeded by 2200 million kilowatts, accounting for percent of the same installed capacity of power plant units, accounting for percent of the total capacity of country s units. According to the development progress above, the total installed capacity of CHP in China will reach GW in From the distribution of our country s cogeneration to see, the heating units of CHP are mainly concentrated in the regions with cold climate like north, northeast and regions with big hot demand such as North China, Northeast and other industries. Guizhou, Yunnan, Tibet, Jiangxi, Qinghai lands are still not have CHP units, distribution imbalance. In the recent years, under the influence of the policy which is big pressure on the small, there will be more and more big CHP units be installed in cities. More than ten thermal power plants have been built in some cities periphery and developing zone, forming the important power supply system. Some private capitals are also optimistic about the cogeneration industry, started to invest in the construction of thermal power plants. 4. Difficulties encountered by cogeneration After 40 years of development of cogeneration. Because the effect of changes in the market environment and the imperfect into development of cogeneration systems and industrial policy measures, there are many difficulties and problems when cogeneration have a rapid development. According to the relative data, most of cogenerations in China except Zhejing are at a loss. According to the typical survey, thermoelectric loss-making enterprises ware 64.7% in 2004, increased by 62.5% in The general thermal power plant was a loss of 10 about million yuan, the maximum loss of 60 million. The loss-making of CHP is expand continue, resulting in the CHP in our country is facing a crisis of survival. 4.1 Difficulties for business of cogeneration Some cogeneration enterprises distributed earlier, the main of them are condensate pumping unit, high-pressure and medium pressure units. These units due to obsolete equipment, high energy consumption, heating system lag, lower heat price, the economic efficiency of enterprises are poor. Some enterprises even face serious long-term losses, has been dominated by government subsidies. Especially in the north, small and medium thermal power plants are particularly difficult, can not afford to implement energy saving technology. 4.2 system problems of electricity, heat price setting Electricity and heat prices should implement government pricing or government 3

4 guidance pricing. But in reality, the price adjustment of electricity and heat of cogeneration is far behind the rise in fuel prices. For a long time, the electricity price is made by our country with the low coal prices, low price. After state canceled the guidance price of electricity and heat, as coal prices continuing rising, low coal prices, low price has been changed to high coal price, low price pattern. Because the high price coal is far exceeded the capacity of power plant, some power plants with low electricity are running in deteriorate conditions, a serious loss. According to statistics, China s coal prices rose rapidly since 2007, the rise rate is more than 10 percent. The coal prices continued to rise in Although the state raised the electricity price twice, can not still make up for the rising cost due to rising coal prices, resulting in the vast losses for the most of corporate. In particular, some CHP companies don t rely on large-scale power groups, small-scale, dispersed ownership, a small amount of electricity and cash flow fragile, they can only by coal in market price, did not enjoy the national plan for the incentive coal price. Meanwhile, due to the continued loss of CHP companies, financing more difficult, financial situation deteriorate further. Some thermal power plants fall into straits that the supply strand breaks and no heat available. 4.3 The selection of model and scale lack scientific principle to local condition From the perspective of energy efficiency of the system and whole point to see, the large heating units that can t reach requirements are waste of resources, whether compared with the ultra-supercritical condensing thermal power or small thermal power units. From an environment point of view the problem is more serious. There for, the development of cogeneration must to be adapted to local conditions, combined with the actual situation to choose the scale cogeneration units. For energy conservation, cogeneration units should be implemented big pressure on the small policy in areas where have conditions. If the local heat load is large and centralized, convenient supply of coal and water, ash handing, environmental capacity allow, the CHP should advocate support when the comparative study that compared with system-wide energy efficiency is energy saving. If the local heat load is population density, economic development, environmental degradation, we don t consider large, medium, and small units proportion. If we mechanical implement the big pressure on the small, it may bring many adverse consequences. 4.4 Lack of substantive support of government Cogeneration industry in China belongs to the edge of the traditional industries. It offers two different energy products-electricity and heat. The production process of these two products is closely related, but unlike the simple relationship between large thermal power plant and the grid, unlike the clear interests between thermal power plant and local government. So it is not mentioned in the existing cogeneration People s Republic of China Electricity Law, making the CHP business no legal basis. Although local governments have support for cogeneration, most of this supports are promote and encourage and other word in document. Finance, 4

5 taxation, environmental protection, transportation and other related departments have also not put the appropriate support measures. No reasonable policy, no government support of favorable conditions, cogeneration s natural advantage become disadvantage. So CHP become inferior enterprises in China. 4.5 Generation and heating operation mode deficiencies How to arrange power generation and heating operation mode, In the case of ensuring the heating, It s very important of Obtaining maximum power generation rate for heating cogeneration units. Currently, power generation and heating operation mode is also insufficient. When heating in winter, power supply for maximum heat, The phenomena of forced to buy thermal is exist, It s serious wasting of energy. Most power plants is in the heating when the heating, unfounded outdoor temperature, it s reasonable to adjustment heating network of sending and returning water temperature, Instead of having been run according to the rated bottled water temperature. It s due to higher temperatures of Bottled water, In order to maintain a comfortable indoor temperature of heating user, there is a phenomenon of opening the window and even the air conditioning in winter, It s serious wasting of heating energy. If bottled water temperature is higher, the circulating flow of water that outside the network will be larger, seriously affecting the hydraulic operating conditions of pump. When the bottled water temperature is high, making it easy to does not draw water for the pump outside the network in booster pump station, local network pipe overpressure explosion may occur at any. In addition, high temperature of bottled water, return water temperature also increased, affecting the safe operation of the low vacuum heating operation of the unit. How to arrange operation mode reasonably and carry out economic dispatch operation, both security and stable operation of the heating network, but also on energy consumption, according to the outdoor temperature has a certain practical significance to improve the economic efficiency of the power plant 5. The policy to promote the rapid of the development of cogeneration Because of Cogenerations obvious energy-saving effect and environmental effect, in line with national industrial policy, which belongs to the sustainable development of industry, and cogeneration is a strong policy of public welfare, and its development should be supported by national policy. 5.1 amendment and perfection the power law, a clear legal status of cogeneration Modify Electricity law, to take into account the cogeneration. Need to modify and improve the power laws, regulations, and establishing the legal status of cogeneration as soon as possible. Cogeneration does not exist in our country's current "power law" in the content, it not suitable for promote energy saving and reduction, promote the healthy development of cogeneration. It has no corresponding status in 5

6 the power industry if cogeneration not into the standardization management of power industry, and their interests can't get legal protection. Therefore recommended that the newly revised Electricity Law fully consider the importance of cogeneration development, updating and development of a separate chapter on cogeneration, is conducive to the development of further regulate cogeneration. 5.2 Rational development of cogeneration units of electricity and heat prices. Cogeneration enterprises are built in the heat load concentrated urban areas, land cost is high, heat net investment cost is large, the boiler equipment investment, high environmental requirements, the investment recovery period is long, the loan burden. In addition cogeneration enterprise is the local public power plant, and the investment for the majority of private, procurement of coal no large group as to rely on, are the market retail coal into the coal, coal is higher than the local fire power plant, therefore cogeneration production price higher than the fire power plant, according to expert estimates and intermediaries assessment thermal power electricity price, the cost is higher than the benchmark price of 32%. Therefore the proposed cogeneration of electricity price to make reasonable price should according to the actual cost and the rate of return, and to consider energy conservation and environmental thermoelectric social benefit. The price of heating thermal power units should be in accordance with local guide price of coal, and a reference power coal price of thermal coal linkage in place by the commodity price departments. Calculation formula of heat price linkage should be scientific, and monthly timely linkage, overcome the numbness practices long lag coal price linkage, because the heat price benefit to local business interests of many heat, heat price long-term losses, need to gradually increase, and as soon as the coal thermal linkage in place, not in place, should increase financial assistance, tax reduction or exemption policies, so as to correct depends on the price situation, promote the benign development of the thermal power industry. 5.3 To improve the environmental protection measures to reduce emissions, accelerate the cogeneration alternative "small boiler" pace The development of cogeneration significance not only for power generation, the key point is to replace the small coal-fired boiler. The efficiency of small boilers can rarely reach 60%, while the efficiency of cogeneration boiler reached more than 90%. A cogeneration enterprises can eliminate hundreds of small boiler Suggested that the relevant state departments as soon as possible to improve the environmental emissions laws, regulations and policies, the deadline for the elimination of existing small boilers, still insist on using decentralized heating boiler, to improve pollution charge standards and other measures, forcing the small boiler shutdown. Accelerate the development of cogeneration central heating, all government departments to strictly control, in the context of central heating, should not built new small boiler decentralized. Development trend of cogeneration of China 6

7 6. Development trend of cogeneration in China The Cogeneration business in China has development more than 50 years, although a certain scale, but can far satisfy the actual needs of users. With the development of the city, the prospects of CHP are very bright, especially in larger cities. With the development of medium and small cities, the demand for cogeneration has become more urgent. 6.1 Large capacity heating unit increasing. Last two years in the construction of cogeneration, our country began to pay attention to the scale of the construcion, the country advocates the large amphibious heating units for the city central heating actively. Previous single machine of 200 mw and 300 mw large heating unit only were built in urban construction. In the past two years they were also built in the city of more than people and the general city.according to thermal power construction dynamic, only in 2005 there were 121 constructions of thermal power engineering approved by the state. The total capacity were mw, about 333 mw average each project. Our country has been biased toward small cogeneration units. And now in the center of the city Beijing, Shenyang, Changchun, Zhengzhou there are and KW of large-scale extraction condensing amphibious units under operation, it shows that our country cogeneration has become the main force of city power supply heating. 6.2 Urban development heat, power and cooling With the industrial development and people s living standards improve, our need for air condition and refrigeration increasingly urgent. With the support of the thermal power systems for industrial steam, winter heating, summer cooling and domestic hot water and other energy sources, the overall efficiency of thermal power plant improve significantly. There has been a rapid increase in the momentum of heat, power and cooling cogeneration. Meanwhile, development in heat, power and cooling in urban can reduce urban pollution and waste of resources, and have a positive to strengthen the urban function. With the implement of the western development strategy in China, the extensive application of natural gas and miniaturized gas area provide an important impetus for heat, power and cooling development. 6.3 Rural development gas, heat, electricity trigeneration. In the former State Planning Commission and other departments to actively support, with coal as raw material, while the production of gas, heat, electricity trigeneration technology research laboratory, has been a success, and through the national small test to identify. Industry test in gas, heat, electricity trigeneration will be carried out on the project, the pilot project has passed the preliminary design. Due to the construction of urban and rural areas on coal gasification, heating and electrification are very urgent, so the research projects received widespread attention. There are specialized companies promoting this work, looking forward to an early and 7

8 successful promotion in everywhere. 6.4 Gas-steam combined cycle power plant began construction More than ten provinces and cities of the fuel structure adjustment become reality, because the construction of west east pipeline project oil gas go to the Shaanxi Gansu Ningxia. Some areas will start construction of gas - steam combined cycle power plant, the reported of the gas turbine power plant be shown in table 16 Conclusions Table 1 The project of construction gas and steam combined cycle power plan name of project Total capacity /MW Thermal power plant expansion Of Wuchang 2 70 Beijing second offsite power plant renovation Beijing Sun Palace Thermal Power Plant 786 BDA Beijing Thermal Power Plant 7 52 Cogeneration power plant of Beijing Electronic City 1 40 Thermal power plant in Zhejiang Yuyao Cogeneration power plant of Beijing Caoqiao Beijing three thermal expansion Conclusions With the current growing concerns about energy efficiency, cogeneration is concerned by every country, not only a large number of energy-efficient cogeneration, but also improves environmental conditions, improvement of living standards, has obvious advantages. The rapid development of cogeneration in the same time, there are many difficulties, China should adjust its policies to conform to trends. Only in this way, can we achieve better overall efficiency. 8. References [1] State Opportunities for Action: Review of States combined Heat and Power Activities. ACEEE, 2002,(9). [2]WU D W, WANG R Z. Combined cooling, Heating and power: A Review [J]. Progress in Energy and Combustion Science, 2006, 32(5/6): [3] HE Ping, SUN Gang, WANG Fei, et al. Heating Engineering [M]. Beijing China Architecture & Building Press, 1933: [4] Wang Zhenming. The new development of the cogeneration [J]. Technical and Economic Power,2007, 19(2): [5] Wu Xuesu. Cogeneration [M]. Xian: Xi an Jiaotong University Press, About the author: Huaxing Lu, Chinese people, in January 1990, female, master. Research direction: energy and power engineering 8