Development of low carbon economy has become the focus of international attention, in which the development of renewable energy is the key issue. After years of construction, renewable energy constructions in China have made remarkable achievements. However, The challenge is still grim. (1) National and local governments need a unified plan for the development and utilization of renewable energy. (2) The public’s awareness of the importance of renewable energy is still insufficient. (3) The technology is not yet mature, objectively limiting the sustainability of the development of renewable energy. (4) The development and utilization of renewable energy is still in the non-commercialization of energy phases. The operation of the market conditions is not yet ripe.
China must take actions to achieve low carbon economy. Scientists are encouraged to invite and innovate to improve the utility of the energy. China's renewable energy resources are very rich. Though cost of renewable energy is quite high, a considerable part has been commercialized.
Commercialization of renewable energy can be further promoted (Zhang JL. 2010). To speed up the process of construction of low-carbon economy by raising consumer awareness of energy conservation is essential. For this reason, we must develop appropriate policies. Taxation is a common and effective way. A lot of the advanced experience from foreign countries in the field of low-carbon communities and low-carbon cities can be learned through international cooperation.
2.1 Low-carbon Economy
The past two years, the topic of low-carbon is fiscally debated, especially in the last year. After the General Assembly in the Copenhagen, the low-carbon has already been the world's largest common topic.
2.1.1 Concept of Low-carbon Economy
What is the low-carbon economy? It is a low energy consumption, low pollution and low-emission-based development model, different from high-consumption and high-growth in the past. The essence and goal of the low-carbon economy is reducing energy consumption per unit of GDP to reduce overall energy consumption to ensure the economic development.
Low-carbon economy is an economic model, based on low energy
consumption, low pollution, low emission which is another major step forward in human society after following agricultural civilization, industrial civilization. The essence of the low-carbon economy is the efficient use of energy, clean energy development, the pursuit of green GDP, core energy technologies and emission reduction technology innovation. In the long term, construction eco-saving and environment-friendly society is the fundamental requirement to achieve sustainable development (Geoffrey Heal. 1998). Its significance lies in: the development of low-carbon economy, improving the efficiency in the use of
resources, energy, reducing the carbon intensity of the economy, can effectively promote the optimization and upgrading of China's economic structural adjustment and industrial structure. Development of low-carbon economy, increases the proportion of renewable energy, and effectively reduces the carbon emissions of the primary energy consumption. From the point of view of international cooperation, related technology joint with developed countries, is conducive to China's medium-and long-term development and long-term stability.
2.1.1 Existing Problems
Because of the shortage of resources and the status of environmental degradation, promoting low-carbon economy in China has reached a consensus. However, as a new model of development, there are still deep obstacles mainly in the following aspects:
1. Costs and the price of a one-way trade-offs constitute the interests obstacles which can not be avoided. The parties of the economic activity of economic entities mainly considered the relationship between costs and benefits. The one-way trade-off of costs and prices under the interests of the regulation of the market orient govern economic behavior of economic agents.2. The traditional mode of economic growth with existing environmental institutional weaknesses format reality system disorders (Li Y. 2009). More than 30 years of reform and opening up, China's economic growth mode is the high consumption of resources and high pollution. Traditional economic growth has inertia so that the transformation of the mode of growth is difficult to be done overnight. In addition at this stage, China's economic construction is still centered and economic efficiency is still one of the main indicators of the assessment achievements. Each region in order to develop the local economy, is likely to choose the quick success of the economic policies to get the achievements, making the low-carbon economy still only stay in the technical level of exploration and in the early stages of development.3. Bleak market demand and strict organizational boundaries restricts the technical barriers of low-carbon economy. In terms of the ordinary consumers in developing countries, the product of the same quality, price advantage is more important than the quality of the environment; Moreover, the average consumer will not be too concerned about green production and its role in environmental protection. The environmental awareness of consumers relies solely on the individual's morality.
1. Provide a system to protect the development of low-carbon economy. First, we should learn from the successful experience abroad, and create relevant laws and regulations to provide legal support for the development of low-carbon economy. Secondly, make relevant reward and punishment policies. Then change the assessment methods of leading cadres in the past, including a clear low-carbon economy into government policy-makers' performance
evaluation system. In the end, establish a new system of evaluation and assessment indicators.
2. Rebuild the social price system to cross the price and cost barriers. On one hand, it is necessary to improve the price formation mechanism of the natural resources, and drive the implementation of the enterprise to achieve a low-carbon economy (Yan LG. 2010). On the other hand, increase the tax to some emissions of polluting enterprises and increase the standard fee in carbon emissions, so that pollution costs significantly rise to encourage enterprises to internalize external costs. Enterprises make the right choice between high pollution costs and cleaner production. Consciously walk the road of low-carbon economy.
3. Establish a green GDP accounting system, a scientific measure of the level of economic development. The so-called green GDP is that green national economic accounting system, which is integrated economic and
environmental accounting. It can be measured as a "real GDP", because it not only reflects the amount of economic growth, but also reflects the quality of economic growth (Li M. 2010). It truly reflects the large system of environmental economic concept of low-carbon economy.
4. Carry out green education and advocate green consumption. All policies’ performance ultimately is closely related to public participation. In order to improve the effect of the implementation of the policy of low-carbon economy, need to strengthen the culture of public environmental awareness (Dan Mahoney. 2002). The green consumer guide green production. Public awareness of the environment determines their consumption preferences. All in all, create a low-carbon economy will eventually be settled in the improvement of the public's environmental awareness.
2.2 Renewable Energy
2.2.1 Differences between Renewable Energy and Non-renewable EnergyRenewable energy plays a crucial role in the development of low-carbon economy (A. Demirbas?2003). Renewable energy refers to a variety of inexhaustible energy, including wind, solar, biomass, hydro, geothermal and ocean energy, with a wide distribution of resources, great potential for the use and sustainable use. It is conducive to people in harmony and nature development. From a strategic height, the development of environment-friendly renewable energy plays an important role in guaranteeing energy supply (L. Graham, N. Muegge, J. Rostkowski, D. Ayyad, and D. Karman. 2006). It has become an inevitable choice for China's sustainable energy strategy. The strategic objective of the national development of renewable energy is to maximize energy supply capacity, promote the energy structure, diversify energy sources and safeguard the security energy supply. But the proportion of renewable energy consumption as a share of China's total energy consumption is still low.
Non-renewable resource is the natural resource that after the human development and utilization, in quite a long time is not possible to renewable. It mainly refers to the various mineral, rock and fossil fuels, such as peat, coal, petroleum, natural gas, metal ores and non-metallic mineral. The restore of non-renewable energy is limited in the world. And it will be used up one day. The difference between non-renewable energy and renewable energy is whether can be replenished from nature in the short-term. Modern energy technology development direction is to seek to save non-renewable energy, and actively develop the use of renewable energy technologies.
Currently, China is in a dilemma with grasping the opportunity for economic growth and low-carbon transition. We must not only follow the general laws of economic and social development, conforming to the trend of the development of low-carbon economy, as well as depending on China's basic national conditions and national interests, looking for a coordination of long-term and short-term interests development paths. Renewable energy is an important energy resource in China, playing a vital role in meeting energy demands, improving the energy structure, reducing environmental pollution, and promoting economic development.
Developing an environmentally friendly renewable energy has become an inevitable choice for China's sustainable energy strategy. The active development of renewable energy sources to reduce dependence on fossil fuels, create a new diversified energy consumption structure and improve the recycling of resources and the level of concentration is significant to adjust and optimize the energy structure, strengthen energy conservation and efficiency, reduce greenhouse gas emissions and develop circular economy and low-carbon economy(V. E. Eidman. 2006).
2.2.2 Renewable Energy Resources Existing in China
China's renewable energy resource bases on a large-scale development. Water is a finite natural resource, which needs sound and sustainable management practices to meet various demands (Kaloyan N. Kenov and Helena M. Ramos, 2012). Wind energy resource is total about 7 to 12 million kilowatts, the annual generating capacity up to 1.4 to 2.4 trillion kWh. The area of solar resource-rich regions accounts for more than 96% of the land area. Surface absorption of solar energy per year is roughly equivalent to 17,000 tons of coal equivalent energy. Currently, an available biomass resource is about 290 million tons, mainly from agricultural organic waste. Development of hydropower resources is total about 600 million kilowatts. Annually provides electricity 2.5 trillion kWh.
However, in 2009, China has overtaken the United States, becoming the world's most carbon emissions than any other country.
The World's Top Five Carbon Emitters in 2009 (Unit: 100 million ton)
2.2.3 Efforts in China
With the growing attention to a low-carbon economy, the pace of development has exceeded expectations and showed a trend of rapid growth. Statistics data of National Energy Bureau show that the first three quarters of 2009 account for 32.9% of new generating capacity in clean energy, increased 5.6% over the previous year. Investments in hydropower, nuclear and wind significantly increased (He HS. 2011).
Rising fuel costs and energy demands, combined with growing concern over greenhouse gas emissions, have led to increased interest in the use of renewable fuels to help meet increasing worldwide fuel demand and reduce atmospheric CO2 emissions from transportation sources (Jing G, E. Peltier, E. Carter, J. Krejci, SusanM Williams and Depcik. 2012). According to the National Renewable Energy Long Term Development Plan, in 2020, the total installed hydropower capacity will reach 300 million kilowatts. The degree of development reaches about 75%. The global environmental change and the issue for long-term availability of traditional oil resources necessitate creating the substitute energy sources that give engine performance at par with the conventional fuel (Nitin Shrivastava, S.N. Varma and Mukesh Pandey. 2012). Among the substitute energy sources, biofuel industry is another way of developing clean energy that is environment friendly. It carbon dioxide emission is equal to it absorptions during crops production (Samuel David Olusegun. 2012). Biomass will generate electricity about 30 million kilowatts and the same 30 million kilowatts from wind. Solar electricity generation will reach 180million kilowatts. Encourage solar water heaters in the promotion and application of the buildings in cities and rural areas to achieve that the total collector area for solar water heaters by 2020 reach 300 million square meters and replace fossil energy 90 million tons of standard coal per year. Utilize rural biomass energy development as an important measure of the development of modern agriculture and the construction of a new socialist countryside. Promote household biogas and livestock farms biogas project and accelerate the promotion of biomass briquette pellet fuel applications. In 2020 biogas use will reach 44 billion cubic meters and the biomass briquette pellet fuel annual use about 50 million tons. At the same time, actively develop biomass liquid fuel energy crops as the main raw material, replacing 10 million tons of oil in 2020(Wang HW. 2008).3. Conclusion
Through the years of great efforts to develop, China's renewable energy development has been in the highest of the world in the overall size. With the growing attention to the country to a low-carbon economy, China will continue to be optimistic about the prospects for the development of renewable energy. In fact, carbon emission pressure rising, creates a broader stage for clean energy, because the development of the low-carbon economy needs the universal use of clean energy. China's proposed new requirements for the development of renewable energy, greatly promoting the development of renewable energy pace. One hand, The government should increase the expenditure of the construction of the low-carbon economy. On the other
hand, the public may raise low-carbon awareness, conserving resources from oneself.
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