Three priority areas were identified for the CDM project development in China. According to the Measures for the Operation and Management of CDM Project in China , t hey are: 1) energy efficiency improvement, 2) development and utilization of new and renewable energy, and 3) methane recovery and utilization. These priority areas represent technologies that the Government of China has indicated strong supports for development and huge potential for future application and duplication as analysed in the following ：

•  Energy Efficiency Improvement

1.1 The current status of China's energy consumption and utilization

As one of the rapidest economy growth countries, China is also distinguished for its energy consumption. Its total energy consumption ranks second in the world, next to America. The total primary energy consumption in 2002 in China was 1.514 billion tce, 527 million tce more than in 1990, signifying an increase of 53%, with an annual average growth rate of 3.6%; to which coal contributed 66.3%, petroleum 23.5%, natural gas 2.6%, hydroelectric power and nuclear power 7.6%.

Energy consumption in China is characterized by the following: (1) Energy consumption is mainly coal based, giving rise to increasingly serious environmental problems. In 2002, coal consumption was 1.42 billion tons; approximately 70% raw coal was directly burnt without washing and dressing. Emissions of carbon dioxide from fossil fuels are the main source of greenhouse gases in China. (2) Consumption proportion of high quality energy is rising. In 2002, the consumption of high quality energy such as petroleum, natural gas and hydropower was 33.7% of the total energy consumption. (3) Industrial energy consumption remains high. In 2002, industrial energy consumption was 68.3% of the total energy consumption, which is apparently higher than that in other developed countries. (4) Residential energy consumption slightly increased but is still at a very low level. The residential electricity consumption per capita is 156 kWh, only 7.7% of that in Japan and 4% in America.

In China, the energy resource undertaking has developed under the guidance of the policy of “developing the energy supply and energy conservation simultaneously with priority giving to energy conservation”, to which much importance attached by the central government. To achieve the target of energy conservation, it is the fundamental solution by relying on the technological improvement and reducing energy consumption.

In recent decade, China's energy saving task has been emphasized on increasing the utilization efficiency of heat and electricity. A great achievement has been made by issuing various energy-saving policies, such as, implementing cogeneration and district heating supply, increasing the efficiency of industrial boiler and kiln, recovery and reuse of residual heat, spreading energy saving equipments and buildings; and also by improving various energy waste technical equipments, accelerating the arrangement and spreading of demonstration projects in those key energy intensive industries, as metallurgy, nonferrous metal, building material and chemical industries; as well as strengthening the scientific management and regulation formulation.

Energy utilization efficiency has improved to some extent in China. Energy conservation has reaped significant economic and social benefits. However, compared with developed countries, energy utilization efficiency is still low in China. In a word, despite China's energy consumption per capita is only the half as much as international average level, the energy consumption for unit production value is 2.4 times more than that of international average level and the unit energy consumption for major industrial products is 40% higher than that of international advanced level, therefore, China is also regarded as one of the highest production value energy consumption countries in the world. The gap in energy utilization efficiency between China and foreign countries indicates that on the one hand, the thoroughgoing work of energy conservation should be urgently conducted; on the other hand, it shows there exists a huge energy saving potential in China, especially with technological improvement, the energy consumption will be efficiently reduced by sufficient application of energy saving technology.

1.2 Targets and emphases of energy conservation in China

China Medium and Long Term Energy Conservation Plan issued by National Development and Reform Commission (NDRC) essentially planned the energy conservation targets and the focus of development by 2010 (the Eleventh Five Years Plan), the targets stated for 2020 are also proposed.

By 2010, energy consumption per 10,000 Yuan GDP (constant price in 1990, the same below) is expected to drop from 2.68 tce in 2002 to 2.25 tce, with an annual average energy conservation rate of 2.2% from 2003 to 2010. The energy conservation potential is expected to reach 400 million tce (amount to emission reduction of 1 billion tons carbon dioxide). By 2020, energy consumption per 10,000 Yuan GDP will drop to 1.54 tce, with an annual average energy conservation rate of 3% from 2003 to 2020. The energy conservation potential is expected to reach 1.4 billion tce (amount to emission reduction of 3.5 billion tons carbon dioxide), 111% as much as the total planned newly increased energy production of 1.26 billion tce during the same period.

To achieve the targets as mentioned above, the 3 key fields and 10 key projects of energy conservation are stipulated in China Medium and Long Term Energy Conservation Plan , and the concrete implementation plan of 10 key projects are being established. By implementing the above 10 key energy conservation projects, the total saving of 240 million tce (including the increments) will be achieved in the “Eleventh Five-year Plan” period.

Yet the promotion of energy saving technology and the construction of energy saving projects badly need a lot of financial support from central and local finances, financial organizations, enterprises and international society. It should be pointed out that Clean Development Mechanism (CDM) is a new significant approach to solve the financing problems of the energy saving projects. Through CDM projects, China's enterprises will obtain certain financial aid and the advanced technology, which will prompt China in achieving sustainable development.

1.3 Energy Conservation potentials of some energy intensive industries

1.3.1 Electric Power Industry

(1) Gap between domestic electric power industry and that of international advanced level is big

Although China electric power industry has achieved greatly in energy conservation, it still has existed obvious gap between domestic and major industrialization countries in the world. It mainly shows as following aspects:

a. The gap is about 60g/kWh, in terms of coal consumption of power supply.

b. The rate of line loss is 2-2.5 percentage points higher than that of international advanced power company.

c. Structure of power generation is irrational, which needs a further optimization. Large capacity unit is a small share.

d. It has insufficient capacity to make non-power compensation and regulatory, due to the weak electric grid.

e. There has a huge potential for implementing power demand side management.

(2) Energy conservation must be carried out in power industry

Nowadays, the level of power consumption is still very low in China. Per capita installed capacity in China was 0.303 kW in 2003; per capita power generation was 1474 kWh; per capita net power consumption was 1205 kWh which was only 58% of the average international level in 2000, and was equal to the level of international major industrialization countries in 1950s-1970s. The percentage of power consumption taken in energy end-use is fairly low, which was only 12.9% in 2003, but it was 18.0% averagely in the world in 2000.

Coal is dominated in primary energy structure of China. It is quite difficult to change the coal-dominated role played in power generation in near term. In 2003, the coal output was 1.67 billion tons and 50% of them was consumed for power generation, which had contributed 80% of national total power generation. By 2020, even if China will adjust and shrink the percentage of coal-based generator, installed capacity of coal-based power is also to be about 600 GW, 2.3 times of current level. This will continuously present a major challenge to coal resource, water resource, bearing of environment and capacity of transport. All in all, because the double checks come from both rapidly growth of power demand and energy shortage, it is urgent for power industry to further adhere to principle of putting energy conservation on a priority position.

(3) Trend of energy conservation technology in power industry

The key technological orientation of energy conservation implementing in the aspects of power industry upgrading and technological renovation is summarized as followings:

(3.1) Optimize the structure of coal-based power generation, develop high parameter, large capacity, water saving and environment friendly power generating units, increase the share of large capacity power generating units

(3.2) Vigorously develop co-generation, and earnestly make renovation of existing coal-based and oil-based power plants

(3.3) Strengthen the electric power grid construction and non-power compensation, practice the power grid economy operation technology, and reduce the losses of power grid

(3.4) Power saving technology at power consuming side

Through adopting the measures of replacing small unit with large ones, co-generation and power unit renovation, coal consumption of power supply can reduce 3.2gce/kWh annually in power industry. By 2010, coal consumption of power supply will be about 360gce/kWh, which has 30gce/kWh lower than 380gce/kWh in 2003. It can save 31.58 million tons of coal and reduce about 80 million tons CO 2 emission annually in electric power industry.

1.3.2 Iron and Steel Industry

(1) Current status of energy conservation in iron and steel industry

Iron and steel industry in China has occupied a pivotal position in the world. In 2004, output of pig iron was 251 Mt, steel 272 Mt, finished steel products 297 Mt and coke 209 Mt. The output of steel shared 26.31% of the world. Iron and steel industry is a typical energy intensive industry, which consumed 274 million tce in 2003, accounted for 16.3% of national energy consumption. This is only second to electric power industry. So it is only to rely on technology improvement and innovation for setting up green iron and steel industry featured by low energy consumption and low resource consumption.

Since1990s, China's iron and steel industry has dedicated itself to adjust its technical process structure. It has achieved a major breakthrough in the following aspects: use blast furnace coal injection and reduce ratio of coke; disuse processes of steel making with melting iron and open hearth furnace (OH); eliminate processes of ingot-blooming-bloom breaking down; eliminate horizontal rolling machine and process of multi-reheating to final production; apply compact working flow, hot charge and hot conveyance technology, and continuous casting. The optimization of structure has greatly improved the level of technical process of China's iron and steel industry, and become a mainstream of energy conservation. At same time, it has also obtained an obvious effect from energy conservation in the aspects of energy saving technology renovation and intensifying management.

(2) Trend of Energy conservation technology and energy conservation potential in iron and steel industry

In iron and steel industry, the following energy conservation technologies and equipments need to be promoted:

(2.1) Coke Dry Quenching (CDQ)

(2.2) Top Gas Pressure Recovery Turbine (TRT)

(2.3) Coal gas power generating technology (CGPG)

(2.4) Pulverized Coal Injection (PCI)

In a ward, in the period of “11 th Five-year” Plan, 2.66 Mtce will be saved and 6.4 Mt-CO 2 will be reduced through CDQ, TRT, improvement of power generation by using blast furnace coal gas as well as recovery and reuse of BOF gas, and PCI.

1.3.3 Cement Industry

(1) Current status of energy consumption in cement industry

Cement sector is a big energy consumer in building material industry. Energy consumption is accounted for about 50% of total energy consumption in building materials industry. Thus, it is the key point for building material industry to save energy. And now, China's cement industry is in the stage of adjusting its technological and product structures. The adjustment focuses on gradually replacing outdated, high energy intensive and producing low quality product technology with the technology of new dry process kiln with precalcinator featured by advanced, low energy intensive and producing high quality products, and also promoting the energy conservation technology of residual heat utilization. By the end of 2002, 222 production lines of new dry process kiln were put into operation, and more than 30Mt new production capacity is under constructed annually. And thus heat consumption dropped to 104kgce/t cement, and power consumption decreased to 100kWh/t cement.

It exists relatively a big gap between domestic and international advanced level in the aspects of scale of cement enterprise, scale of facilities, indicators of technical process, energy consumption and resources comprehensive utilization. At present, the comprehensive energy consumption per ton cement is 26% higher than that of the most advanced world level.

(2) Trend of energy conservation technology and energy saving potential of cement industry

The trend of saving energy in cement industry is to phase out outdated technical process and equipment and develop advanced technical process. Through energy saving technology, it will reduce energy consumption per unit product, decrease energy and resource consumption and mitigate greenhouse gases emissions, so as to realize the sustainable development in cement industry.

The tendency of energy saving technology in cement industry is shown as followings:

(2.1) Develop the new dry process kiln precalcinator technology, increase the percentage of new dry process cement clinker.

(2.2) Promote energy efficient grinding equipment and power generating technology by using residual heat recovered from cement kiln.

(2.3) Improve the performance of existing large and medium sized rotary kiln, mills and drying machines for the purpose of energy conservation; gradually phase out mechanized vertical kiln, wet process kiln and long dry process kiln and other outdated cement production technologies.

(2.4) Dispose combustible waste materials by using cement rotary kiln.

By 2010, among the production lines with daily output of over 2000 tons cement, every year 30 power generating units with using medium and low temperature residual heat should be installed, and thus 3 Mtce will be saved per year. After adopting above-mentioned energy saving measures, by 2020, comprehensive energy consumption per ton cement will be dropped to 129 kgce from 150kgce in 2004 and the accumulative energy saving potential will be 178.5Mtce. I t can save 11.2 million tons of coal and reduce 28 million tons CO 2 emission annually in Chinese cement industry.

•  Development and Utilization of New and Renewable Energy

The use of renewable energy resources plays a key strategic role in maintaining balance between energy supply and demand in China. The Chinese Government has therefore consistently promoted renewable energy. At present, traditional, noncommercial renewables (e.g. fuel wood) provide China with energy of over 300 million tons of standard coal equivalent (tce) annually. Small hydropower installations provide about 100 billion kilowatt hours (kWh) of power annually, accounting for five percent of China's total electricity output. Adding in other renewable resource applications, China's total annual use of renewables surpasses 12,000 Petajoules (PJ), accounting for 15% of the nation's total energy use.

2.1 Wind Power

2.1.1 Development Status

With its huge land and long coastline, China has abundant wind resources. According to estimates by the China Meteorology Research Institute, land-based, exploitable wind resources represent a potential power generation capacity of 253 GW. (Note: This estimate is based on wind resources at a height of ten meters above the ground.) The institute has further estimated ocean-based wind resources to represent an exploitable potential of about 750 GW, so that the total estimated wind power potential of China is about 1,000 GW. Areas rich in wind resources are located mainly along the southeast coast and nearby islands and in Inner Mongolia, Xinjiang, Gansu Province's Hexi Corridor, and in some parts of Northeast China, Northwest China, North China, and the Qinghai-Tibetan Plateau. Aside from this, there are also certain areas in China's interior that are rich in wind resources. China has large marine areas; and ocean-based wind resources are plentiful. With current technology, wind turbines can be installed in the ocean up to 10 kilometers away from the coast and at ocean depths of up to 20 meters. Since 2003, the National Development and Reform Commission has organized the investigation on the wind energy resources in the whole country, to get more accurate information of wind resource, and it is expected to conduct the work in 3-5 years.

By the end of 2004, there were total 43 wind farms in 14 provinces in China, and total grid-connected installed capacity of wind power was 764 MW. Most wind turbines' size is from 600kW to 1.5MW. 197MW were installed in 2004 and the annual growth rate was 34%. Currently, China is the tenth in the world in terms of total installed wind power capacity. Aside from grid-connected installations, China also has about 200,000 stand-alone small-scale wind turbines (with installed capacity of 25 MW) that provide electricity to rural households located in remote areas.

Basically China has mastered the manufacture of large-scale wind turbines of 750 kW or less and is in the process of developing megawatt-scale turbines, which are expected to be available in 2005. China has also established 43 wind farms and has mastered wind farm operation and management. The nation now has qualified technical personnel in the areas of wind power design and construction. Thus, a sound base for developing large-scale wind power in China has been developed.

2.1.2 Potential for Carbon Emission Reduction

Wind power is one of the renewable technologies that can be applied in large scale in near future as it is in the stage of near-commercialisation. Almost all wind projects are suitable for CDM because of high power cost. According to the development plan of renewable energy made by the Chinese government, the target of large-scale wind farms is 4GW and 20GW in year 2010 and year 2020 respectively. And after 2020, wind power will be in entire commercialisation stage and will develop more rapidly. In 2030, the total capacity will reach 150-200GW, and can become the third power resource (after coal and hydropower) in China. Therefore, the potential of wind power project for CDM is 20GW in capacity, 46TWh of annual power generation and 11 million tons of carbon emission reduction.

2.2 Small Hydropower

2.2.1 Development Status

Water resources appropriate for small-scale hydropower are plentiful in China. According to the results of China's latest hydropower resource survey, the potential total capacity of small-scale hydropower that could be feasibly developed in the country is 125GW. The resource base is widely distributed, including sites in over 1,600 counties (or cities), spreading over 30 provinces (or provincial-level municipalities) in China. Among the 1,600 counties, 65% are located in Southwest China; and the small-scale hydropower resources of this region account for over 50% of total national potential capacity.

The Chinese Government has implemented policies that strongly support small-scale hydropower and has included small-scale hydropower in its rural electrification plans. Small-scale hydropower has already played a very important role in the electrification of China, particularly in rural areas. About one-third of China's counties rely on small-scale hydropower as their main source of electricity. China has further made the building of small-scale hydropower stations a critical component of rural energy development in its Western China Cropland Conversion Program and its Western China Energy Development Program, providing special funds derived from Government bonds for small-scale hydropower development. At present, existing small-scale hydropower stations, with an installed capacity of 35 GW, represent about 28% of the total projected potential capacity. China holds the leading position in the world in the fields of design, engineering, management and equipment manufacturing of small hydropower.

2.2.2 Potential for Carbon Emission Reduction

It is expected that during the period between 2020 and 2030, China's small-scale hydropower resources will be almost fully developed, with a capacity of 100 GW, accounting for about 10% of China's total installed power capacity at that time. According to the National Renewable Energy Development Plan, the installed capacities of small hydropower will reach 50GW and 75GW, with annual power generation of 165TWh and 250TWh, in 2010 and 2020 respectively. The carbon emission reduction will be 40 million tce and 60 million tce.

Small hydropower is one of the priorities for CDM in China, especially in the southwest areas of China, there are abundant resource of small hydropower, and the government is implementing the National Replacing Firewood by Small Hydropower Program, with objectives of supporting the implementing two national programs, namely Natural Forest Protection Program (which includes logging bans and logging reductions over much of the nation's natural forests) and Sloping Cropland Conversion Program (which calls for the conversion of much of the nation's sloping cropland to trees and grasses), thus there are large potential for small hydropower CDM project in these areas. Currently, there are three CDM projects under development. One is in Yunnan, one is in Hunan, and the other one is in Gansu. From 2005 to 2010, it is expected that new installed capacity of small hydropower will be 15GW, and the new increased carbon emission reduction will be 12 million tce. From 2010 to 2020, the relative numbers will be 25GW and 20 million tce respectively.

2.3 Biomass Energy

2.3.1 Development Status

China's main biomass resources are agricultural wastes, scraps from the forestry and forest production industries, and municipal waste. Agricultural wastes are widely distributed. Among them, the annual production of crop stalks alone surpasses 600 million tons; and crop stalks suitable to energy production are estimated to represent a potential of 12,000 PJ annually. Wastes from the processing of agricultural products and manure from livestock farms in theory could yield nearly 80 billion cubic meters of biogas. Scraps from forestry and forest product industries represent a resource equivalent to 8,000 PJ per annum. Furthermore, with the implementation of China's Natural Forest Protection Program and its Sloping Cropland Conversion Program , it is expected that the amount of scraps from forestry and forest product industries used in energy applications will increase substantially, with the potential of reaching 12,000 PJ per annum by 2020. Finally, “Energy Crops” are a biomass energy resource with the potential for commercialisation. There are many types of energy crops that are suited to grow in China. Chief among these are rapeseed and other edible oil plants and some plants that grow in the wild, such as sumac, Chinese goldthread, and sweet broomcorn. By 2020, such crops could potentially yield over 50 million tons of liquid fuel annually, including over 28 million tons of ethanol and 24 million tons of bio-diesel.

At present, biomass energy resources in China are utilized mainly through conventional combustion technologies. Biomass gasification, biomass liquefaction, and biomass power generation technologies, however, are gradually being developed. For gasification, the main method being promoted and used is anaerobic fermentation, though at the same time technology for the direct gasification of biomass resources is being developed. China currently has a total of over 12 million household biogas digesters and over 1,500 industrial-scale biogas plants, which together produce over five billion cubic meters of biogas annually. In terms of biomass liquefaction technology, China is in an investigative and experimental phase. Currently the main technologies developed and in use are ethanol fuel technology and bio-oil technology. China has already established two large ethanol fuel production bases, one in the north and one in the south, with a total annual production capacity of over one million tons. Production of bio-oils in China has reached about 500,000 tons annually. Biomass power generation in China, with an installed capacity of almost 2,000MW, consists mainly of combined heat and power (CHP) in sugar mills and power generation using rice husks. Other types of biomass power generation, such as that achieved through biomass gasification or hybrid fuel technologies, have not yet reached significant scale in China.

2.3.2 Potential for Carbon Emission Reduction

Both the grid-connected power generation projects (sized at MW level) and village power projects (sized at 10kW to hundreds kW), based on straw and stalks, wood and forest residuals, bagasse, and municipal solid waste etc., are all potential CDM projects. In 2004, the total installed capacity of biomass power generation was 2GW, with power generation of 5TWh. It is predicted that the capacities will reach 5.5GW and 20GW, with 20TWh and 80TWh of annual power generation, and with 5 million tons and 20 million tons of carbon emission reduction, in 2010 and 2020 respectively. Furthermore, the potential for biogas utilization will be 5 billion cubic meters and 20 billion cubic meters in 2010 and 2020, equivalent to 2.5 billion cubic meters and 10 billion cubic meters of methane.Thus the amounts of carbon emission reduction for this part will be15 million tons and 60 millions tons. Totally, the potentials of carbon emission reduction from the sector of biomass utilization will be 17 million tce and 80 millions tce in 2010 and 2020 respectively.

2.4 Landfill Gas

2.4.1 Development Status

In China, the municipal solid waste (MSW) and the landfill gas (LFG) are taken as biomass resource from the view of energy utilization. However, considering the large contribution of LFG to GHGs, LFG is taken as a special sector of renewable energies in this report. At present, the annual MSW output is over 100 mbillion tons, and over 80% are disposed by landfill. MSW in China is expected to reach 150 and 210 million tons per annum in 2010 and 2020 respectively. In 2010, If 70% is disposed by landfill, and considering annual 80 cubic meters of LFG is generated for one ton of MSW, the annual LFG amount will be 8.4 billion cubic meters. And in 2020, If 60 percent of MSW is disposed by landfill, about ten billion cubic meters of LFG could be produced.

By the end of 2004, there were three landfill sites with the operation of recovery and utilization of landfill gas. About 70,000 cubic meters of LFG are used per day totally. That is the first step of China in the utilization of LFG. At present, there are over ten projects in building or in the stage of feasibility study. LFG recovery and utilization becomes a hot point especially in the field of CDM. The State Environment and Protection Administration released the National Action Plan of LFG Recovery and Utilization in 2001, showing the attention and action from government.

2.4.2 Potential for carbon emission reduction and potential projects for CDM

LFG utilization is potential CDM project with evident carbon emission reduction benefit. If considering 10% of LFG can be recovered and utilized by 2010, LFG recovery and utilization will be 840 million cubic meters, equivalent to 420 million cubic meters of methane. If considering 50% of LFG can be recovered and utilized by 2020, LFG utilization will be 5 billion cubic meters, equivalent to 2.5 billion cubic meters of methane. Thus the amounts of carbon emission reduction for this part will be 2.5 million tons and 15 millions tons in 2010 and 2020.

2.5 Summary

Renewable energy is in a rapid development stage in China, and some technologies are in commercialisation or near commercialisation and have large development potential from resource, technology and industry points. Renewable energy has begun to play a role in the energy structure, and it has the potential for large scale development and occupy a certain ratio. According to the national target, renewable power will be 12% of the total power capacity in China in 2020. It is expected that it will reach 30% or even more in 2040s and renewable energy will be an important substitute energy at that time.

Till 2020, the major renewable technologies for CDM project will be wind power, small hydropower, and biomass power and LFG utilization. From 2005 to 2010, the new installed capacity of project of these technologies will reach 25GW, and the increased carbon emission reduction will be 37 million tons. From 2010 to 2020, the new installed capacity of project of these technologies will reach 55GW, and the increased carbon emission reduction will be 101 million tons. Total annual carbon emission reduction will be 138 million tons by 2020. Considering 15 years of the lifetime of projects, the accumulated carbon emission reduction will reach 2 billion tons, equivalent to 7.5 billion Certificated Emission Reductions (CERs).

•  Methane Recovery and Utilization

3.1 China coalbed methane(CBM) reserve

CBM is a non-conventional natural gas accompanying coal, with its reserve equivalent to conventional natural gas. CBM is a clean energy. Developing and utilizing CBM can not only increase energy supply but also improve coal mine safety and reduce greenhouse gas emission.

China is one of the major coal producers in the world, and it is also one of the countries possessing the richest coal resources. Its coal reserve, including the proven reserve and the future reserve, is around 5 trillion metric tons ， ranking the top in the world. Meanwhile, China also possesses rich CBM resources, with its CBM resources between 300-2000m in depth 30-35 trillion m3. Since these CBM resources are distributed in different coal-bearing basins featuring different coal-forming periods and different types of reserve bed, there are wide differences in their reserve depths, exploration degrees, etc., which brings about some difficulties for successful CBM recovery. According to the statistics, the gassy mines and gas burst mines account for 48% of the key state-owned coal mines in China.

3.2 Current situation of China CBM recovery technologies

The CBM recovery technologies in China fall into two categories, underground drainage and surface development. As the main technologies to develop coal mine gas at the present time and in the near future, the underground drainage technologies have been applied in a great number of coal mining areas. The surface development technologies mainly include surface standard well technologies and surface gob well technologies.

The underground CMM （ Coal Mine Methane ） drainage in China started up early, and currently the drainage technologies have been fully mature, basically taking a leading role in the world, with a complete system of underground drainage technologies, which is suitable for the CMM drainage under various geological conditions. The common underground drainage technologies include current coal seam drainage, adjacent coal seam drainage, gob area drainage and comprehensive drainage.

For the adjacent coal seam drainage, the drilling site is deployed in the auxiliary air return way of the working face, and the drainage hole is drilled in the cracked zone formed by the working face and arrives at the adjacent coal seam. The adjacent coal seam pressure-release CMM drainage technology is now most extensively applied in China. When the gas liberation from the adjacent coal seam is greater than 30m3/min, the drainage rate using this technology could be as high as above 85%.

There are two ways for CBM surface recovery, CBM drainage in virgin coal seams, and CMM drainage in mining areas. Since 1990, CBM surface recovery technologies have been tested and spread in China, and great progress has been made so far, but a breakthrough remains to be made in large-scale CBM commercial development.

In recent years, with China putting stress on coal mine safety, the input in CMM drainage systems has been increased, and the CMM drainage amount has increased rapidly. In 2003, the CMM drainage amount in China reached 1.521billion m3.

Figure 1 The CMM drainage amounts in China during 1990-2003

3.3 Current status of CMM development and utilization in China

China began utilizing CMM at the end of 1970. Until now, over 100 CMM utilization projects have been completed, all of which are located in the coal mining areas, and most of them are designed to supply the household fuel gas for the purpose of improving the living standard of the citizens in the coal mining areas. In recent years, with increasing awareness of environmental protection, China has liberalized the natural gas price, and CMM has been given more recognition as an energy resource. Therefore, a great number of CMM projects have been developed for power generation, industrial fuel gas production, etc.

3.3.1 CMM power generation

CMM power generation is a way to use CMM with multiple benefits. It converts CMM into electric power, which not only makes the transportation convenient but also effectively reduces the greenhouse gas emission.

In recent years, CMM power generation has developed very rapidly in China. The gas combustion power generators in CMM power plants can be divided into two types, gas combustion turbines and gas combustion engines. Gas combustion engines are of small size, portability, high heat efficiency (as high as 40%) and high adaptability to CMM concentration change, among other advantages, suitable for small-scale power plants. Gas combustion turbines are featured of high intensity power with 50MW or 100MW per unit, but their power generation efficiencies are usually around 30%, which are suitable for large-scale CMM power plants.

At the present time, main CMM power projects in China include the 120MW CMM power project in Jincheng Coal Mining Group, gas comprehensive utilization project in Huainan Coal Mining Group, 20MW CMM power project in Songzao Coal and Power Company, and CMM power project in Shuicheng, Guizhou.

Since gas combustion engines have higher heat efficiencies, all these projects use domestic or foreign gas combustion engines in order to improve power generation efficiencies and comprehensive utilization efficiencies of underground drained gas.

3.3.2 CMM for civil use

Currently, China CMM is mainly for civil use ， accounting for above 70% of the total CMM utilization. The average methane concentration in the underground drainage gas is 30-50%, and the gas could be sent directly to the households, cafeterias, hospitals, schools, etc. in the mining areas. Since there are a small number of households in the mining areas, the large-scale civil use must be based on cities.

At the present time, the main CMM projects for civil use in China include: CMM supply by Fushun Mining Area to Shenyang City, CMM supply as fuel gas to Yangquan City, CMM supply by Fuxin Mining Area to Fuxin City, and CMM supply by Tiefa Coal Mining Group to Diaobingshan City.

3.3.3 CMM Industrial Utilization

CMM industrial utilization mainly includes industrial fuel and chemical production. Although CMM utilization focuses on producing carbon black and formaldehyde in past years with low economic effectives, now it moves to be as industrial fuel replacement of industrial coal gas, natural gas, liquefied petroleum gas or coal.

Currently the CMM utilization projects are undergoing includes Tiefa CMM provided to ceramics plant in Faku project and Yangquan CMM used for alumina roasting project.

3.4 Potential Emission Reduction from CMM Utilization Projects in China

The coal output was up to 1.956 billion ton and the gas drained from underground was only 1.8 billion m 3 in 2004 in China. It is predicted that the coal output will be over 2.1 billion ton in 2005. CMM will be more than 17 billion m 3 (pure CH4) released from coal mining processes every year which equivalent to 183 million ton CO2. In which the gas from ventilation air accounts for 91% (see figure 2) with low than 1% concentration, emitted into atmosphere directly, which is relatively difficult to use.

Figure 2 CMM Sources Type in 2004 in China

Another characteristic of CMM in China is low utilization ratio for the gas from coal mines which accounts for nearly 65% of the total extraction. This should be attributed to the fact that methane recovery and capture is just ensuring work safety underground as an auxiliary to coal mining. Thus methane recovery ratio is only about 23% in the coal mines where have installed methane recovery system underground. Based on the experiences of coal mines, in case of making full use of recovered methane and facilitating methane recovery by encouraging its utilization, the recovery ratio could be up to over 50% under the condition of current technologies and equipment in China. Additionally, in the past two years, Chinese government pays more attention to coal mine safety, strengthens work safety inspection and management step by step, established the guideline of “ Draining Gas Before Mining, Monitoring and Controlling, Coal Production depended on Ventilation ” ,which will result in more methane recovery systems to be established and existing systems to be retrofitted.

It is expected that methane output from underground will be over the point of 3 billion m 3 soon in several years. The emissions reduction of CO 2 will be up to 23.5 million ton from methane destroyed only calculated on the utilization ratio of 60%.

Additionally, the ventilation air methane utilization projects are developing by coal mining areas and research institutes. Currently the methane released from ventilation air is morn than 15 billion m 3 each year in the country. Considerable emissions reduction will be achieved if this part of resource can be used appropriately.

As estimated, by 2010, the utilization quantity ratio by large and medium coal mines will be 80% of total CBM CMM extracted that year , i.e. 1 . 6 billion m3 00 Mm3 . If half of it could be developed as CDM project, the total emission reduction potential will be 13 4.8 m b illion ton of CO2e.