Renewable energy development prospects, the future can be controlled climate warming
In twentieth Century, the development of human civilization depended on the exploitation and utilization of fossil energy such as coal, oil, natural gas and so on. However, these fossil energy reserves are limited, and the excessive use of fossil energy has also caused serious harm to the earth's environment, so that the human living space has been a great threat. Will be held in Paris, France, the United Nations climate conference will be on the control of climate warming multinational collaboration, which is the focus of energy use caused by pollution emissions is one of the key governance.
In order to reduce the pollution of the environment and public health hazards, more effective development and utilization of new energy sources has become an important breakthrough in the protection of the environment and improve the quality of the environment. Now, people have used solar and wind energy, nuclear energy and other clean energy to replace fossil energy, the clean energy not only low pollution, and inexhaustible, beautiful dream can realize human sustainable development.
Solar: real weather
Human use of solar energy has a long history, as early as more than two thousand years ago, people know that the use of steel to focus solar light on four sides to ignition and the use of solar energy to dry agricultural and sideline products. In fact, the solar energy as an inexhaustible supply of clean energy, has great potentiality for development. The International Energy Agency data show that if the 4% of the world's desert solar photovoltaic system installed, enough to meet the needs of the global energy. While the United States launched the "photovoltaic building plan", "millions of European photovoltaic roof plan", Japan's "Asahi plan" and China launched the "bright project" is in the world solar energy boom.
Although solar energy is recognized as a clean energy, but it also has its own limitations. First, although the total amount of solar radiation reaching the earth's surface is very large, the energy density of the solar radiation is very low. But also by the day and night, the seasons, geographical latitude and altitude and other natural conditions of the restrictions and clear, cloudy, clouds, rain and other random factors. Secondly, the development of solar energy utilization, and some aspects of the theory is feasible, technically mature. But some solar energy utilization device, because of the low efficiency, high cost, in general, the economy can not compete with conventional energy.
However, with the development of science and technology, the design of the thin film battery has overcome the shortcomings of low conversion rate. At present, the world to build a photovoltaic power plant, low price so power generation technology to make up for the demand for electricity is part of the big city. And the future of solar power will become an important part of the global total, some experts predict that the future development of solar energy will replace the fossil energy and even nuclear power to become the world's first.
Wind energy: low cost and huge reserves
In nature, the wind is a renewable, non polluting and huge reserves of energy. With the global climate warming and energy crisis, the development and utilization of wind power are stepping up to the world. The utilization of wind energy is mainly driven by wind power and wind power in two forms.
Wind energy is a clean source of energy. As long as the choice of the appropriate location, the cost of wind power is very low. And wind power facilities are more three-dimensional facilities, but also to protect the land and ecology. However, wind energy utilization is limited by the geographical position, wind speed is not stable in many areas, so the energy generated is not stable. In addition, wind power generation, wind turbines will emit a huge noise, on the surrounding environment has also caused some damage.
Wind energy organization in the world to the future development of wind energy analysis, said that due to the low risk characteristics of wind energy and the world's demand for clean and reliable energy, wind energy will be more and more attention and investment in the future. It is expected that by 2020, the global wind power installed capacity of at least 1500GW, wind power is likely to reach 12% of the world's electricity consumption.
Ocean Energy: a variety of ways
80% of the earth is covered by ocean, and there is a strong energy in the ocean. Ocean energy refers to a variety of renewable energy sources, including tidal energy, wave energy, ocean current energy, sea water temperature difference, seawater salinity difference, and so on. These energy resources are renewable and non polluting environment, and it is a new energy to be developed and utilized.
Although the ocean can also be inexhaustible, but there is no consensus on the best way to get energy, large ocean energy projects may destroy the natural flow of water, tidal and ecological systems.
From the current technology development, tidal power generation technology is mature, has reached the stage of business development, has built the Rance power plant, power plant, the China Canada Annapolis Jiangxia power plants have been running for many years; wave energy and tidal energy is still in the stage of technical research, Britain, Denmark, Norway, Italy, Australia the United States, Chinese built a variety of wave energy and tidal energy device, to improve the technology, and gradually into practical applications; also in the beginning of the study of temperature difference energy, only the United States to build a power plant in thermal energy, technology exploration.
Geothermal energy: more stable than the solar energy
Geothermal energy is a renewable resource, which is extracted from the earth's crust, and this energy comes from the interior of the earth, and exists in the form of heat. According to scientists, the future geothermal energy in all renewable energy in the fourth place, only to wind, solar and hydropower.
Compared with wind and solar energy, geothermal energy is stable and reliable, and it is not affected by the weather. Depending on the geographical structure, the long-term cost of geothermal energy is likely to be lower than that of the coal, once the geothermal location and the construction of the power generation turbine, the cost of electricity is almost zero. Geothermal energy in the earth's core energy, can be used to replace part of the nuclear energy. According to statistics, 10 km below the surface of the earth's crust of geothermal energy is 50 thousand times the world's oil and natural gas reserves.
However, the development cost of geothermal energy is higher, and the cost recovery period is long. Geothermal projects and oil or mining engineering, the size of the heat source is not known before the development. A 20 megawatts of geothermal power station needs about $7 million to assess the cost, in addition to the need to 20 million to $40 million of the exploitation of the funds, however, once the judgment mistake, all the investment will be put into the water. Conversion down, 1 megawatts of geothermal energy needs to invest $3 million 500 thousand, while the same energy of coal is only $1 million 200 thousand. In addition, geothermal resources from exploration to commercial operation, generally require 5 to 7 years, in contrast, wind or solar power investment payback period of only 12 to 18 months.
Nuclear power: danger and benefit
Nuclear energy is the energy use of nuclear fission in nuclear reactors to generate electricity released by the way. It is very similar to thermal power generation. Is a nuclear reactor and steam generator to replace the thermal power generation boiler, nuclear fission can replace fossil fuel chemical energy.
Unlike fossil fuels nuclear power generation as emissions of polluting substances into the atmosphere, so nuclear power does not cause air pollution. And nuclear power does not produce carbon dioxide that will increase the earth's greenhouse effect. In addition, the cost of nuclear power generation, the proportion of fuel costs is low, the cost of nuclear power is less vulnerable to the impact of the international economic situation, so the power generation costs compared to other power generation methods are stable.
However, the nuclear power plant will produce high and low level radioactive waste, which has radioactive rays, so it must be carefully handled. And the nuclear power plant thermal efficiency is low, and the ratio of the average fossil fuel power plants emit more heat into the environment, so the nuclear power plant thermal pollution is serious. The most serious is that there is a large number of nuclear power plant reactor radioactive substances, if released in the accident to the outside world, will cause harm to the ecology and the people.
Japan's Fukushima nuclear accident has been a full 4 years, it was predicted that the international nuclear promotion and construction plans will be shelved for a long time, but the actual situation is not the case. Energy is the key to the development of society, and nuclear power is an important means to help social and economic development. At present, many countries around the world have developed nuclear power projects for the next 20 years to expand the program to help economic development. I believe that with the continuous renewal of technology, the development of nuclear power will be less and less, nuclear power will be better for human services.
The Paris climate conference, which is at the end of November, has less than 1 months. Before the day, the French Foreign Minister Fabius in Paris climate conference held a warning, if the meeting failed to negotiate, the earth will fall into a big disaster". Believe that during the meeting, delegates to reach a global agreement, the global joint efforts to control the temperature rise of not more than 2 degrees Celsius, while the development of alternative energy sources is bound to be one of the important means.