What are the new energy sources developed by human beings?

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 energy forms 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 two 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.

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.

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 have realized that oil and other energy sources will be exhausted, so they have paid attention to the development of wind energy.

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%.

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 stands out with its unique advantages of light weight, no pollution, high calorific value and wide application, and will become an ideal energy source in 2 1 century. Hydrogen energy can be used as fuel for airplanes and automobiles, and also as power for propelling rockets.

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.