What are the materials of new energy?

All forms of new energy come directly or indirectly from the heat generated by the sun or the earth. Including solar energy, wind energy, biomass energy, geothermal energy, nuclear fusion energy, water energy and ocean energy, as well as energy generated by biofuels and hydrogen from renewable energy. It can also be said that new energy includes all kinds of renewable energy and nuclear energy. Compared with traditional energy sources, new energy sources generally have the characteristics of less pollution and large reserves, which is of great significance to solve the serious environmental pollution problem and the depletion of resources (especially fossil energy) in the world today. At the same time, because many new energy sources are evenly distributed, it is also of great significance to solve the war caused by energy.

According to the world's assertion, resources such as oil and coal mines will be reduced at an accelerated rate. Nuclear energy and solar energy will soon become the main energy sources.

The United Nations Development Programme (UNDP) classifies new energy sources into the following three categories: large and medium-sized hydropower; New renewable energy, including small hydropower, solar energy, wind energy, modern biomass energy, geothermal energy and ocean energy (tidal energy); Infiltrate biomass energy.

Generally speaking, conventional energy refers to energy that is technically mature and has been used on a large scale, while new energy usually refers to energy that has not been used on a large scale and is being actively developed. Therefore, coal, oil, natural gas and large and medium-sized hydropower are regarded as conventional energy sources, while solar energy, wind energy, modern biomass energy, geothermal energy, ocean energy, nuclear energy and hydrogen energy are regarded as new energy sources. With the progress of technology and the establishment of the concept of sustainable development, the industrial and domestic organic wastes that used to be regarded as garbage have been re-recognized, and have been deeply studied, developed and utilized as a material for the utilization of energy resources. Therefore, the resource utilization of waste can also be regarded as a form of new energy technology.

The energy resources that mankind has just developed and utilized and need further research and development are called new energy sources. Compared with conventional energy, new energy has different contents in different historical periods and scientific and technological levels. In today's society, new energy usually refers to nuclear energy, solar energy, wind energy, geothermal energy, hydrogen energy and so on.

According to the category, it can be divided into: solar wind power generation, biomass energy, biodiesel, ethanol, new energy, automobile fuel cell, hydrogen energy, garbage power generation, energy-saving geothermal energy, dimethyl ether and combustible ice. [Edit this paragraph] Overview of new energy It is estimated that the solar energy radiated to the earth every year is 65.438+0.78 billion kilowatts, of which 50-65.438+0.000 billion kilowatt hours can be developed and utilized. However, due to the scattered distribution, it can be used very little at present. Geothermal energy resources refer to the total heat content of rocks and water bodies within 5000 meters below land. Among them, the global geothermal energy resources with high temperature above 150℃ within 3 km of land are10.4 million tons of standard coal, and some countries have started commercial development and utilization at present. The world's wind energy potential is about 350 billion kilowatts, and it is difficult to use it economically because of the intermittent dispersion of wind power. If the technology of energy transmission and storage is greatly improved in the future, the utilization of wind power will increase. Ocean energy includes tidal energy, wave energy, seawater temperature difference energy and so on, and its theoretical reserves are very considerable. Limited by the technical level, it is still in the small-scale research stage. At present, because the utilization technology of new energy is still immature, it only accounts for a small part of the total energy needed in the world, and its future development prospects are great. [Edit this paragraph] Overview of common new energy forms Solar energy

Solar energy generally refers to the radiant energy of sunlight. The main utilization forms of solar energy are photothermal conversion, photoelectric conversion and photochemical conversion.

In a broad sense, solar energy is the source of a lot of energy on the earth, such as wind energy, chemical energy, water potential energy and other forms of energy caused or transformed by solar energy.

The methods of using solar energy mainly include: solar pool, which converts the energy contained in sunlight into electric energy through photoelectric conversion; Solar water heaters use the heat of sunlight to heat water and use hot water to generate electricity.

Solar energy can be divided into three types:

1. Solar photovoltaic panel module is a kind of power generation device that generates direct current under sunlight irradiation, and it is composed of thin solid photovoltaic cells made almost entirely of semiconductor materials (such as silicon). Because there are no moving parts, it can run for a long time without any loss. Simple photovoltaic cells can provide energy for watches and computers, while more complex photovoltaic systems can illuminate houses and supply power to the power grid. Photovoltaic panel modules can be made into different shapes, and the modules can generate more electricity when connected. In recent years, photovoltaic panels have been used on roofs and building surfaces, and even as a part of windows, skylights or shielding devices. These photovoltaic facilities are usually called photovoltaic systems attached to buildings.

2. Solar Thermal Energy Modern solar thermal energy technology gathers sunlight and uses its energy to generate hot water, steam and electricity. In addition to using appropriate technology to collect solar energy, buildings can also use the light and heat of the sun by adding appropriate equipment in the design, such as giant south-facing windows or building materials that can absorb and slowly release solar heat.

3. Solar energy integration: plants use sunlight for photosynthesis to synthesize organic matter. Therefore, plant photosynthesis can be simulated artificially, and a large number of organic substances needed by human beings can be synthesized, thus improving the utilization efficiency of solar energy.

nuclear power

Nuclear energy is the energy released by the nucleus by transforming its mass, which accords with Albert Einstein's equation e = MC 2; Where E= energy, m= mass and c= constant of light speed. There are three main forms of nuclear energy release:

A. Nuclear fission energy

The so-called nuclear fission energy is the energy released by fission of some heavy nuclei (such as uranium -235, uranium -238 and plutonium -239). ).

B. Nuclear fusion energy

Two or more hydrogen nuclei (such as hydrogen isotopes-deuterium and tritium) combine to form a heavier nucleus, and the reaction in which mass defects simultaneously release huge energy is called nuclear fusion reaction, and the released energy is called nuclear fusion energy.

C. Nuclear decay

Nuclear decay is a natural and much slower form of fission, which is difficult to use because of its slow energy release.

Main problems in the utilization of nuclear energy;

(1) The resource utilization rate is low.

(2) The nuclear waste produced after the reaction has become a potential factor endangering the biosphere, and its final treatment technology has not been completely solved.

(3) The safety of the reactor needs constant monitoring and improvement.

(4) The constraint of nuclear non-proliferation, that is, the plutonium -239 produced by nuclear power plant reactors is controlled.

(5) The investment cost of nuclear power construction is still higher than that of conventional energy generation, and the investment risk is greater.

ocean energy

Ocean energy refers to all kinds of renewable energy contained in seawater, including tidal energy, wave energy, ocean current energy, seawater temperature difference energy, seawater salinity difference energy and so on. These energy sources have the advantages of being renewable and not polluting the environment, and are strategic new energy sources that need to be developed and utilized urgently.

Wave power generation, according to scientists' calculations, the electric energy contained in the waves on the earth is as high as 90 trillion degrees. At present, navigation buoys and lighthouses at sea have been illuminated by electric power generated by wave generators. Large wave generator sets have also come out. China is also studying and testing wave power generation, and has made a beacon light power generation device. In the future, there will be a wave power plant in every ocean in China. Wave energy will make great contribution to China electric power industry.

Tidal power generation, according to the estimation of the World Power Congress, by 2020, the global tidal power generation will reach1-300 billion kilowatts. The largest tidal power station in the world is the Longs Estuary Power Station on the English Channel in northern France, with a power generation capacity of 240,000 kilowatts, which has been in operation for more than 30 years. China has built Jiangxia Tidal Power Station in Zhejiang Province, with a total capacity of 3000 kilowatts.

wind energy

Wind energy flows under the radiation of the sun. Compared with other energy sources, wind energy has obvious advantages. Its reserves are 10 times that of hydropower, and it is widely distributed and never exhausted, especially suitable for islands and remote areas with inconvenient transportation and far from the main power grid.

Wind power generation is the most common form of using wind energy for contemporary people. Since Denmark developed wind turbines at the end of 19, people realized that oil and other energy sources would be exhausted, so they paid attention to the development of wind energy and used it to do other things.

1977, the Federal Republic of Germany built the world's largest power windmill in blom Porte, a famous wind valley in Schleswig-Holstein. The windmill is150m high, each blade is 40m long and weighs18t. It is made of glass fiber reinforced plastic. By 1994, the global wind turbine assembly machine capacity has reached about 3 million kilowatts, and the annual power generation is about 5 billion kwh.

biomass energy

Biomass energy comes from biomass, and it is also a form of energy in which solar energy is stored in organisms in the form of chemical energy. It comes directly or indirectly from the photosynthesis of plants. Biomass energy is stored solar energy and the only renewable carbon source, which can be converted into conventional solid, liquid or gas fuels. Biomass energy resources on the earth are abundant and harmless. The earth produces173 billion tons of matter through photosynthesis every year, which contains energy equivalent to 10-20 times of the world's total energy consumption, but the current utilization rate is less than 3%.

Present situation of biomass energy utilization

By the end of 2006, China had built rural household biogas digesters18.7 million, domestic sewage purification biogas digesters1400,000, and more than 2,000 livestock and poultry farms and industrial wastewater biogas projects, with an annual biogas output of about 9 billion cubic meters, providing high-quality living fuel for nearly 80 million rural people.

China has developed various fixed-bed and fluidized-bed gasifiers to produce natural gas from straw, sawdust, rice husk and branches. In 2006, there were more than 800 sets of wood and agricultural products drying equipment and nearly 600 village-level straw gasification centralized gas supply systems, with an annual output of 20 million cubic meters of biomass gas.

Geothermal energy

The heat source in the earth can come from gravity differentiation, tidal friction, chemical reaction and energy released by radioactive element decay. Radioactive heat energy is the main heat source of the earth. China is rich in geothermal resources and widely distributed. There are 5500 geothermal spots and 45 geothermal fields, and the total geothermal resources are about 3.2 million MW.

hydrogen energy

Among many new energy sources, hydrogen energy stands out with its unique advantages such as light weight, no pollution, high calorific value and wide application, and will become the most ideal new energy source in 2 1 century. Hydrogen energy can be used in aerospace, automobile fuel and other high-heat industries.

Ocean infiltration energy

If there are two kinds of salt solutions, one with high salt concentration and the other with low salt concentration, then when the two solutions are put together and separated by osmotic membrane, osmotic pressure will be generated, and water will flow from the low concentration solution to the high concentration solution. What flows in rivers is fresh water, and what exists in the ocean is salt water, and there is also a certain concentration difference between them. At the mouth of a river, the water pressure of fresh water is higher than that of seawater. If a turbine generator is placed in the estuary, the osmotic pressure between fresh water and seawater can drive the turbine to generate electricity.

Marine osmotic energy is a very environmentally friendly green energy source, which does not produce garbage or emit carbon dioxide and does not depend on weather conditions. Can be said to be inexhaustible. In waters with high salt concentration, the power generation efficiency of osmotic power stations will be better, such as the Mediterranean Sea, the Dead Sea, the Great Salt Lake in Yancheng, China, and the Great Salt Lake in the United States. Of course, there must be fresh water supply near the power plant. Bud mikkelsen, head of Norwegian Energy Group, estimates that the global annual power generation can reach 654.38+0.6 trillion kWh by using ocean penetrating energy.

water-power

Water energy is a kind of renewable energy and clean energy, which refers to the kinetic energy, potential energy, pressure energy and other energy sources of water bodies. In a broad sense, hydropower resources include river energy, tidal energy, wave energy, ocean current energy and other energy resources; In a narrow sense, hydropower resources refer to the hydropower resources of rivers. This is conventional energy, primary energy. Water can not only be directly used by human beings, but also be the carrier of energy. Solar energy promotes the water cycle on the earth and makes it last. The flow of surface water is an important link. Areas with large drop and large flow are rich in hydropower resources. With the decrease of fossil fuels, water energy is a very important and promising alternative resource. At present, hydropower generation in the world is still in its infancy. Rivers, tides, waves and swells can all be used to generate electricity.

It can be decomposed into combustible hydrogen by electrolysis and photochemical decomposition of water molecules, and can be used as a new and multi-purpose energy source to replace the existing mineral energy source. The decomposition process of water molecules is simple and easy, with less investment and quick results. This brings a broad prospect for the comprehensive utilization of water energy. On the earth, water is a liquid substance that can be seen everywhere. Hydrogen fuel prepared by water decomposition device can be used in automobile, aerospace, thermal power generation and other industrial and civil aspects, which greatly alleviates the excessive dependence of human beings on mineral resources.