One morning, Wang Min, a young farmer, did not go to work in the field as usual but went to a factory in the village, where quite a lot of villagers were already waiting at the gate with their horse-drawn carts loaded with straws and stalks. All these straws and stalks are to be used as fuels in that factory, and villagers change straws and stalks brought forth into manure made of combustion ashes with a fold of money in their hands. Possibly, this will be the most common scene of a power plant with straws and stalks as fuels in the future countryside.

If the above-said scene is surprising, perhaps the following scene is not strange at all. Once the summer harvest begins, a lot of straws and stalks are burnt on fire in farmlands in many areas in North China, wasting a great amount of precious resources while at the same time polluting the environment.

New approach to the treatment of straws and stalks

"Minor Power Generation Project with Straws and Stalks" is not only a good way to handle straws and stalks but also a fine approach to solving the energy supply in the vast countryside in China and increase farmers' incomes.

The so-called "Minor Power Generation Project with Straws and Stalks" refers to mini-sized power generation system with straws and stalks as fuels, which can include other biomass resources like chaffs, straws, timbers, etc. "Minor Power Generation Project with Straws and Stalks" are determined with an installation capacity below 3,000 kw, quite different from other large-scale biomass power generation systems.

Since 2003, "Minor Hydroelectric Projects Replacing Fuels" have been launched in over 20 counties across China with distinct achievements in economic and social benefits. Nevertheless, "Minor Hydroelectric Projects" are only suitable for areas where water resources are comparatively abundant, especially certain mountainous areas and highlands; as for the vast plains that are not provided with such resources but with relatively abundant biomass resources like straws and stalks, "Minor Power Generation Projects with Straws and Stalks as Fuels" should be developed.

China has a great population but relatively less lands. As the per capita area of farmland is about one mu (666.66m2), a household can earn RMB3,000 at the most in case that there are five people in a household owning five mu of farmlands, which can then produce 5 tons of grains at the most with profits of RMB600 per ton. Considering that each mu of farmlands can produce one ton of straws and stalks that can sell at RMB150/ton, each household can increase profits of RMB750, that is, the income of a household can increase by 25 percent.

On condition that some of the farmers could get jobs in minor power generation plant with straws and stalks as fuels, the income would be even higher. If there are 300 people in a village, it can be possible to have 30 people, about 10 percent of all villagers, work in such power plant as shown in the investigation. With the full spread of minor power generation projects, 8~10 percent of households and population in rural areas will be benefited. Minor power plants with straws and stalks as fuels can absorb a part of labors, thus relieving the problem of surplus labors in rural areas to some extent.

In addition, minor power generation plant with straws and stalks as fuels can also be an important channel to ensure the energy supply for rural areas and conduct the communications between rural and urban civilization, which seems to be more prominent and more important for some remote mountainous areas. In a certain sense, as to mountainous areas, power transmitting circuits not only bridge light but also transmit and deliver civilization from cities.

Exploitation opportunity gradually becoming matured

"Minor Power Generation Project with Straws and Stalks" are favorable to China's economic development in many ways. As the heat value of two tons of straws and stalks are equal to that of a ton of coal and out of China's current yearly output of over 600 million tons of crop straws and stalks there are nearly 300 million tons can be used as energy resources, that means, nearly 150 million tons of coal can be replaced by straws and stalks. If the proportion of power generation plants with renewable energy resources as fuels like straws and stalks can catch up with the advanced level abroad, the situation being short of coal resources will be relieved effectively.

As straws and stalks used to generate electricity power, rolling soot covering the open country in the north will disperse away gradually, thus reducing pollutions to the environment resulted from the emission of sulfur dioxide and farmers'random burning of straws and stalks. The sulfur content in straws and stalks is only a quarter or one fifth of that in coal. By using straws and stalks as fuels, the emission of sulfur dioxide each year can be decrease by 1,500 tons.

China's first mixed combustion generation unit using straws and stalks as the fuels has been running steadily since it was put into operation in the Shiliquan Power Plant of Huadian Power International Corporation Limited on last December 16th. Calculated by running 7,236 hours per year, such a unit can use 105,000 tons of straws and stalks as fuels each year, equivalent to 75,600 tons of standard coal.

In the next place, as a distributive energy supply system, "Minor Power Generation Project with Straws and Stalks" are propitious to the promotion of security of the electricity network. As "Minor Power Generation Project with Straws and Stalks" fundamentally follows the principle of getting access to the network at the nearest place, the long-distance transportation of electricity power can be avoided and line losses at the end sections of the electricity network can be reduced, thus being propitious to the saving of electricity resources. In the meantime, "Minor Power Generation Project with Straws and Stalks" can be used as a supplementary means for the peak adjustment of the electricity network as well, which is of certain significance for the guarantee of the effective operation of the electricity network.

Finally and most importantly, electricity power using straws and stalks as the fuels is a kind of renewable resource, which constitutes the essential difference from electricity power using coal as the fuel. In face of the increasing drying up of fuel energy resources, the renewable advantages enjoyed by straws and stalks become more conspicuous. Also, a new way to construct the cycling economy in rural areas can be found by making use of straws and stalks as a kind of resource. Either the operational pattern of direct combustion power generation or gasification power generation is adopted, the derivatives from the power generation link can be made use of effectively. For instance, tars can be made into a raw material used in chemical industry; ashes can be used as manure to be returned to the farmlands. Thus, a benign cycle of "coming from the soil and being returned to the farmlands" will be realized in deed.

In recent years, the highly effective utilization of such biomass energy resources as straws and stalks has been taken as an important issue in the development and promotion of technologies in China. The promulgation and implementation of the Law of the People's Republic of China on Regenerable Energies has also created a favorable external environment for the development of biomass energy resources. For example, the State Development and Reform Commission issued the Trial Measures on the Pricing of Electricity Power Generated out of Renewable Resources & Expenditure Apportionment, explicitly stipulating that RMB0.25 will be added to the price of electricity power generated out of biomass energy resources on the basis of standard prices for coal electricity power; as a result, the price of electricity power generated out of biomass energy resources will reach about RMB0.65/kw, further expressing the government's support to the development of straw electricity power generation.

Editor: Yan