Solar energy as a clean energy source, its transformation and use should also be clean, this is the whole society on the solar photovoltaic expectations. However, after several years of explosive growth, the industry is existing a few problems that solve urgently, cleaner production is one of them.
In recent years, with the rapid expansion of production capacity, the photovoltaic industry pollution and energy consumption problems of concern and question. In this context, the green peace through combing the photovoltaic industry in various production processes, technology is not the implementation of pollution reduction and consumption reduction target barriers, China solar photovoltaic industry has the ability, should also be clean production, make solar power the low carbon energy truly clean.
" China is the world's largest photovoltaic equipment production country, China's photovoltaic industry should not only for the world to provide clean energy, its own production also should and must be clean. In fact, the PV to become truly clean, near zero emission energy, and no impassable barrier." Greenpeace climate and energy project director Li Ang told reporters.
Photovoltaic production of high energy consumption
In March 28th, the international environmental organization Greenpeace released" Chinese Photovoltaic Industry Cleaner Production Research Report" ( hereinafter referred to as" report" ) pointed out: to consumption, photovoltaic power generation is low carbon energy; at the same time, China PV industry to realize the clean production and no technical bottleneck, photovoltaic industry can realize the environmental protection and reduce the cost of the win-win.
And in fact, the photovoltaic industry clean production situation is not satisfactory. Upstream polysilicon links to industry as an example, at present China's polysilicon has more than 70 enterprises, only 20reached in 2011promulgated national" polysilicon industry access conditions" requirement, explain China's polysilicon enterprises only less than 1/3 of the energy consumption and environmental protection standards can meet the basic requirements of clean production. These 20 enterprises scale is uneven, some scale of production achieves10 thousand tons of class, some small, some still under construction, no actual production, to production enterprises not 10.
In addition to the polysilicon links, domestic downstream PV enterprises up to700 ~800, only a handful of listed companies issued corporate social responsibility report, disclosure of enterprise energy consumption level and the" three waste". Now, look, this is the only enterprise environment information disclosure photovoltaic channel. This exposes China PV enterprises awareness of cleaner production is insufficient, still stays in the slogan and form. The resulting illegal, illegal hidden troubles, such as in a conventional pollution control have been many loopholes exist.
Production of high energy consumption, also known as photovoltaic power generation is a kind of low carbon energy?
" Report" think, general photovoltaic power generation system service life is25 years, according to a study estimating, solar photovoltaic energy recovery period of only 1.3years, that is to say, photovoltaic power generation in the wake of the nearly 24years are zero carbon emissions. Amorphous silicon solar cell photovoltaic power generation of carbon emissions for33 ~ 50g / kWh, while the coal carbon emissions for96.7g / kWh, fuel generating carbon emissions for525G / kWh, gas generating carbon emissions for377g / kWh. Photovoltaic power generation is only the fossil energy sources of carbon emissions from1/10 to1/20, is the real low carbon energy.
" Report" pointed out, the polysilicon links in energy consumption and emissions of "three wastes" be the first to bear the brunt, therefore also has the largest emissions of pollutants and reduce the energy consumption of space, and the cost is reduced the potential maximum. In the aspect of production enterprises should strive to innovation, will clean production technology to improve as the core competitiveness of enterprises.
" Three wastes" not up to the standard
Reportedly, the polysilicon manufacturing is the production of energy consumption in the course of the highest link.
According to the domestic photovoltaic industry energy consumption level, put forward the following estimation. Does not include from silica sand to metallurgical silicon and energy consumption; with the average level of the industry:8 tons of silicon material production 1MW silicon, polycrystalline silicon photovoltaic system calculated from the beginning to the whole industry chain of energy consumption of 1.032~ 1.658kWh / Wp.
" Three wastes" emissions standards is the main reason for what? " Report" think there are mainly three: first, the local government supervision of enterprises adverse, lax enforcement of the law; second, enterprises do not discharge standards of the low cost, resulting in some enterprises, in the conventional pollutants: waste water, exhaust, solid waste, including biological oxygen demand, chemical oxygen demand of various indicators of emission is not satisfactory; third on the special position, enterprise personnel ( e.g. management positions ) training is insufficient, management is lax can also cause environmental pollution accident generation.
" Report" think, as a mature energy conversion technology, photovoltaic production may occur in the process of pollution can be solved through the clean production technology.
For example, in the production of polysilicon links of silicon tetrachloride in the emissions, the actual through cold hydrogenation technology to improve the conversion rate of silicon tetrachloride, again through the use of closed cycle to solve. Closed cycle use can effectively solve the silicon tetrachloride and trichlorosilane emission problems, and achieve the purpose of recycling and reuse. And" crystal branch energy" accidents emerge in hydrofluoric acid pollution accident, can be achieved by using alkali neutralization measure, will be completely precipitated further processing of fluoride ion. At the same time, involves links, waste must be strictly in accordance with the rules, by the competent departments or units. These measures and technology in China has enterprises, technology is not clean production bottleneck.
However, the majority of domestic enterprises or clean production stays in the end treatment stage, and not the cleaner production concept from the source, not the upgrading of production technology, the management cost is high, and the effect is not ideal.
In addition, the lack of supervision and unified industry production standards, and the various local government in the development of new energy in the process, the blind pursuit of quantity, local authorities and industrial parks in order to attract foreign investment to reduce waste emissions standards, or does not strictly implement the relevant environmental standards, supporting the pollution control facilities are not fulfilled reach the designated position, makes the PV industry environment there is a certain hidden trouble.
At the same time, in the early development of polysilicon industry supply situation makes the production enterprises ignore the standards for environmental protection and clean production. While the domestic polysilicon industry because of the late start, is also facing the problem of backward technology and equipment.
Cleaner production to be standardized
China Association of resources comprehensive utilization Chang Yu said:" at present, domestic enterprises can not do 100% of silicon tetrachloride and trichlorosilane production cycle, did not achieve" zero emission standard". From the point of international experience," near zero emissions" is not technically exist bottlenecks. The future, polysilicon enterprises through industrial upgrading and technological transformation, to further reduce energy consumption, the reduction and cost reduction potential is tremendous."
" Report" is mentioned, in the energy shortages, price higher area, appeared to repeat construction tendency, some areas of illegal, illegal approval, did not approve build first, edge number of edge construction phenomenon. These projects lack of supporting the comprehensive utilization, environmental protection standards. The advanced foreign enterprises energy consumption can be 80~ 100 kWh / kg, production costs less than $25/ kg, and most domestic enterprises' energy consumption is far from the advanced level, the product also does not have competition ability, costly, caused part of the backward production capacity appears.
" Even after taking into account the photovoltaic manufacturing process energy consumption and carbon emissions, photovoltaic power generation carbon emissions is still the fossil energy from 1/10 to1/20, in energy conservation and emission reduction with there is nothing comparable to this superiority." Li Ang said.
" Report" also pointed out, the industry production is at present an unsatisfactory condition, enterprise and government is having cannot the responsibility of shirk. Some companies will still stay in the end treatment clean production stage, the management cost is high and the effect is not ideal; and the environmental protection departments in the photovoltaic industry development in the process of matching the lack of supervision, pollution control facilities are not in place, the photovoltaic industry in the development process of buried hazards.
" By sacrificing the environment to reduce production costs is tantamount to quench a thirst with poison, the photovoltaic industry to seek long-term healthy development, starting from the source of clean production is the inevitable choice." Li Ang added," PV market is going through the winter, it is enterprise production technological opportunity, from a long-term point of view will promote the sustainable development of the industry. Only the cleaning capacity to deal with the long-term challenges."
Therefore, Greenpeace calls for the government to formulate more comprehensive photovoltaic industry clean production standards, and the establishment of certification system, as the market access standards, regulate and guide the future direction of the development of photovoltaic industry. The enterprise also respond to social issues annual clean production report, open and transparent disclosure of all aspects of the environmental indicators and level of energy consumption.
