Current energy situation and strategic countermeas

  • Detail

China's energy status and strategic countermeasures

I. Introduction

in recent years, energy and its related environment have become the most concerned hot spots in the world. All countries are solving energy and environmental problems from their own national conditions. For China, due to the shortage of energy resources per capita (especially oil, gas and water), the limited environmental capacity (also resources), and the fragile ecology in the west, this problem is particularly serious. It will greatly restrict the sustainable development of China and leave a living space for the generations of the Chinese nation. In recent years, China's GDP has been developing at a rate of 10% per year, energy consumption has increased sharply, and the environment and ecology are deteriorating day by day. This kind of disorderly and predatory development model for nature has become unsustainable. In fact, it has caused very serious and irreversible consequences. The punishment of nature has been constantly highlighted and will continue to increase. In such a severe situation, every worker in the energy field, especially the government officials at all levels, should fully consider the burden

II. Several unchangeable realities

-- coal is and will continue to be the main energy source in China (until 2050 or later). Although the proportion of coal in the total energy (energymix) will gradually decline (from 75% to 60%, the total amount will continue to increase)

-- the proportion of coal used for power generation will increase from 50% to more than 70%

-- coal mining and direct combustion have caused serious ecological and environmental pollution problems. SO2, NOx, mercury, particulate matter and CO2 above 70%% - 80%% are caused by direct combustion of coal

-- due to the shortage of oil in China, the liquid fuel for vehicles still has to find a way from coal based alternative fuel. In 2005, China imported about 130 million tons of crude oil and its product oil, and it is estimated that China will import 250 million tons of oil in 2010, with an external dependence of more than 50%%, which will cause a series of energy security problems. Of course, coal is also a scarce product for China, but it can still be "tolerated" compared with other energy resources. If one eighth of the coal output is used for the production of vehicle liquid fuel (or methanol, or dimethyl ether, or coal to liquid) every year, it will not bring great imbalance from the perspective of total energy supply

in the long run, grain ethanol, which was widely popularized in China in the previous period, is difficult to replace as a share, because China's specific situation is that it is a major premise to feed 22% of the world's population with 7% of the world's arable land. According to the existing technical level, 3.5 tons of grain can be used as 1 ton of ethanol. Considering the calorific value of ethanol, 5 tons of grain can be used as 1 ton of gasoline equivalent. In addition, 0.5-0.8 tons of coal will be consumed for fermentation and dehydration. If 10million tons of equivalent gasoline were to replace it, 50million tons of grain would be needed, which is more than one tenth of China's total grain output. This is impossible. Of course, it can be considered to use cassava, sweet sorghum and other crops to produce ethanol, or straw and other cellulose (the technology has not been commercialized yet), but the latter has the problem of large-scale collection and transportation

-- it is difficult to reduce greenhouse gas emission under the condition of direct coal combustion, because collecting CO2 with a concentration of about 13%% - 14%% from the large volume flow of flue gas in the power plant will consume a lot of additional energy, reducing the power generation efficiency by about 10%. At present, China's greenhouse gas emissions have ranked second in the world, and are still growing rapidly in recent years. If this continues, it will surpass the United States and rank first in the world in 10 years or a little longer

-- it is difficult for renewable energy (mainly wind energy, solar energy and biomass energy) to occupy a certain proportion in the total energy balance before 2020, which is very different from other countries in Europe in terms of national conditions. In some European countries, their total energy consumption has no longer increased (or increased very little), and the development of renewable energy has gradually replaced the fossil energy currently in use. However, China is experiencing a sharp increase in total energy consumption. The installed capacity of power generation equipment (mainly coal-fired power generation) alone is 60-80gw per year, more than three Yangtze Gorges. In this rapid growth, renewable energy can play a very limited role, let alone replace the original fossil energy consumption. For example, according to the national plan, the installed capacity of wind power generation will reach 30GW by 2020 (24 times that of 2005). Considering that the average full load working time of each unit of installed capacity is only 2500 hours, 30GW of wind power is equivalent to about 12gw of thermal power, that is, about 1.2% of China's total installed power generation capacity of 950-1000gw in 2020

III. five severe challenges faced

1 The huge pressure of total demand

from 2000 to 2020, the country plans to quadruple the national GDP and double the energy consumption, which means that the energy elasticity coefficient should be 0.5. However, in the last three years, the coefficient is above 1.3, that is, the energy demand will be far greater than the planning. From the perspective of the development trend under the same output and melt quality, China's industry has entered the heavy chemical stage. According to the historical law of the development of countries around the world, the stage of rapid growth of energy consumption seems insurmountable. The question is whether we can supply such a large demand for primary energy, and whether the pollution caused by it has enough environmental capacity? How to solve it

2. Shortage of liquid fuels

it can be seen from the figure that China's oil dependence on imports will increase from 40% to 50% and 60%. How to consider energy security? How to accelerate the replacement of oil? How can China's automobile industry and petrochemical industry adapt to this situation with an innovative development model? In terms of alternative fuels for vehicles, China should take this opportunity to walk out of the road of independent innovation

3. Serious environmental pollution. The main pollutants are SO2, NOx, pm2 Hg and CO2, 80% of these pollutants are caused by the application of fossil energy, especially the direct combustion of coal. At present, 30% - 40% of China's regions (especially the southwest) have acid rain, and respiratory diseases are increasing. What needs to be carefully studied is the "tolerable" environmental capacity of these pollutants in China

4. Greenhouse gas emissions

at present, the world emits more than 25 billion tons of CO2 every year. The concentration of CO2 in the air has increased from 280ppm to 380ppm since more than 150 years of industrialization. At present, it is growing at a rate of 3ppm/year. After a long-term debate, the disastrous consequences of greenhouse gases on the earth are unrealistic, and scholars all over the world have reached a consensus. Therefore, the world is taking various measures to reduce CO2 emissions. China has become the 37th signatory of the "Kyoto Protocol" in 2002. In general, as a big negative country, China is bound to undertake the task of reducing greenhouse gas emissions by a certain amount or even by a large margin in the near future. Therefore, from a strategic perspective, we should seriously consider the relevant strategic technologies and policies on how to reduce CO2 emissions in stages from now on. Otherwise, China will pay more for this in the next few decades

5. 800million farmers and the supply of energy for urbanization

so far, a considerable number of farmers have not received good energy services. They still rely on local agricultural wastes (straw, firewood, etc.) as their main energy. In some places, they are even cutting down forests and destroying the ecology. In addition, China's urbanization rate is increasing by 1% every year, and nearly 10million people enter the new process every year. The advantage of this process is that it is a simple and convenient town. According to statistics, the per capita energy consumption of urban residents is 3.5 times that of rural residents. Where should this huge share of energy come from? How to combine the construction of a new socialist countryside with the provision of modern energy services in line with China's national conditions to the vast rural areas and newly-built medium and small towns, so as to reduce ecological damage, reduce indoor pollution and improve farmers' quality of life... This is an important part of the overall energy strategy

the above five points are severe challenges facing China's energy. Energy strategy, energy technology and energy policy should take solving the above five points as the starting point and end result

IV. several important strategic countermeasures

the whole energy and environmental issue is a huge systematic project, involving science, technology, culture, historical tradition, education, diplomacy, politics and other aspects, and these aspects are coupled and influenced each other. This paper only puts forward several important strategic countermeasures from the technical level, which is far from explaining the whole problem. Even the science and technology mentioned can only be a part

1. Energy conservation oriented

although China is short of resources per capita and has great supply pressure, on the other hand, the energyintensity per unit of GDP is very large, about 5-6 times that of Japan. The reasons are multi-level:

● industrial structure. Such as industries with high energy consumption and low added value; The manufacturing industry lacks independent innovation and is at the low end; The tertiary industry is underdeveloped...

● the reasons for the relatively backward technology. The unit energy consumption of power generation, cement, steel making, electrolytic aluminum, etc. in China is 20% - 30% lower than that of advanced technology

● policy reasons. Energy saving is often a soft indicator. Policies are not matched with each other, implementation is not effective, and statistics are chaotic. Generally, there are many calls but few implementation. Energy consuming enterprises, institutions and individuals have no real driving force and awareness of energy conservation

● reasons of traditional habits, culture, concepts and morality

in a sense, people do not take energy conservation as their code of conduct, indiscriminately imitate the West in terms of consumption patterns, and even take pride in luxury and luxury. The circular economy and resource-saving society advocated by the central government mostly follow the slogans very quickly, with more superficial articles, more political achievements and projects, and less down-to-earth practical work

from the perspective of science and technology, energy conservation has a very large coverage. There is a lot of work from basic research to application research, to the R & D and commercial promotion of energy-saving products. For example, enhanced heat and mass transfer, two-phase and multi-phase flow, efficient and rational utilization of renewable energy (solar energy, wind energy, biomass energy, ground source cold and heat energy, and the composite system composed of these energy applications), new energy storage (heat and electricity) devices, new thermal power systems, integration and optimization of complex industrial systems...

in fact, energy conservation itself is a kind of energy, and it is the most "clean" energy, In this regard, China has great potential, which provides a very broad world for the vast number of scientific and technological workers and policy makers to give full play to their talents

2. Modern utilization of coal as mentioned above, the primary energy in China is mainly coal for a long time, and the direct combustion of coal causes serious environmental problems. Therefore, the modern utilization of coal - the polygeneration system led by coal gasification is the strategic direction corresponding to the serious challenges of China's energy problems. The block diagram of coal based polygeneration system is as follows:

coal is gasified into syngas (co+h2), which can be used to produce chemical raw materials, liquid fuels (synthetic oil, methanol, dimethyl ether) and electricity after purification. The energy flow, material flow and exergy flow of these production processes are coupled together according to the optimal principle, and the basic investment, unit product cost and pollution emissions (sulfur and mercury SAMPE Shanghai Branch

Copyright © 2011 JIN SHI