New energy refers to various forms of energy that directly or indirectly come from the heat generated by the sun or the earth's interior, in addition to traditional energy sources such as coal, oil, and natural gas. It is generally believed that new energy sources include solar energy, wind energy, biomass energy, geothermal energy, hydropower and ocean energy, as well as biofuels and hydrogen energy derived from renewable energy sources. The United Nations Development Program (UNDP) divides new energy 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; and traditional biomass energy.
From the perspective of the development process of new energy, breaking through the many bottlenecks faced by conventional energy is the fundamental reason for its growth. Conventional energy is mostly a form of material energy that has undergone the long evolutionary process of the earth, with limited reserves and limited exploitable amounts, and it is difficult to meet the growing needs of mankind for economic and social development. In addition, the huge damage to the environment caused by conventional energy in the process of utilization has also led people to seek new forms of energy to achieve sustainable economic and social development to a large extent. In order to break through the economic and environmental constraints of conventional energy, new energy came into being and gradually entered the sight of mankind.
Schematic diagram of conventional energy
Different from conventional energy, new energy has its own distinctive characteristics. The common feature of new energy is that it is rich in resources, can be recycled, and has no or little pollution. They are energy sources with far prospects and near practical results. Pay attention to and develop new and renewable energy sources, which can not only be used as a supplement to conventional energy sources, to solve the resource bottleneck faced by current economic development, but also to improve the environment, prevent air pollution, and provide better energy for future social development.
Schematic diagram of new energy
So far, new energy and renewable energy have experienced four development climaxes. The first climax of the world's renewable energy development was after the 1973 oil crisis. Affected by high oil prices, the economic development of developed countries and regions such as the United States, Japan, and Western Europe has been hit hard. The developed countries have established their own renewable energy research and development institutions and formulated corresponding special plans to strengthen the research and application of renewable energy. , And strive to reduce dependence on energy. Although renewable energy resources are abundant, the energy density is low, limited to the technological level at the time, the conversion efficiency of renewable energy is low, the cost is high, and it is difficult to compete with traditional fossil energy. The development of new energy is like a "county flower". The second stage was marked by the 1992 Conference on Environment and Development held in Rio de Janeiro, Brazil. The meeting passed important documents such as the Rio Declaration and Agenda 21, and determined the relevant environmental responsibility principles. The concept of sustainable development has gradually formed, and the development and utilization of renewable energy has once again attracted attention and mentioned on the agenda. The third stage is after entering the 21st century, with the increasingly prominent global climate issues and the increasing contradiction between energy supply and demand, countries around the world have adjusted their energy policies from the perspective of sustainable development and the perspective of ensuring energy supply security. Further incorporate the development of renewable energy into the national development strategy. On February 16, 2005, the "Kyoto Protocol" came into effect, promoting countries that have undertaken emission reduction obligations to complete their greenhouse gas emission reduction targets. At the same time, developed countries have undertaken the obligation to reduce carbon dioxide and other six greenhouse gases. Energy support has been further increased, and new energy and renewable energy have begun to flourish. The fourth stage is the UN Climate Change Conference held in Copenhagen, Denmark in December 2009. This is another epoch-making global climate agreement after the "Kyoto Protocol." Have a decisive impact. This is a meeting hailed as "the last chance to save mankind." The "Copenhagen Agreement" upholds the "common but differentiated responsibilities" principle established by the "United Nations Framework Convention on Climate Change" and its "Kyoto Protocol", and has made arrangements for the implementation of mandatory emission reductions by developed countries and autonomous mitigation actions by developing countries. And reached a broad consensus on key issues such as global long-term goals, financial and technical support, and transparency. Since the Copenhagen Climate Conference in Denmark in 2009, low-carbon economy and low-carbon society and concepts have begun to spread around the world. The realization of "low-carbonization" of economic development and social operation has become a topic of common concern for all mankind in the new century. New energy and energy Renewable energy has become an important choice for countries to implement "low-carbon" development.
Renewable energy schematic diagram
Renewable energy is favored by developed countries because it is clean, pollution-free, renewable, and meets the requirements of "low-carbonization". All developed countries in the world have formulated and implemented a series of grand plans and projects. The European Union is the fastest growing region of renewable energy in the world, and it is also the region that has benefited the most. In 1997, the European Union issued a white paper on the development of renewable energy, and established that renewable energy will account for 12% of the EU's total energy consumption in 2010, and the ambitious goal of reaching 50% of the energy composition of the EU countries in 2050.
In April 2004, the major EU countries reached a consensus and formulated renewable energy development goals for 2010 and 2020 respectively. Both the United Kingdom and Germany promised that the proportion of renewable energy in 2010 and 2020 will reach 10% and 20% respectively. %; Spain said that in 2010 its renewable energy power generation ratio can reach more than 29%; some Nordic countries have proposed the use of wind power and biomass power generation to gradually replace nuclear power strategic goals.
Japan implemented the "New Sunshine Project" in 1993, which covers the "Sunshine Project" in 1974, the "Moonlight Project" in 1978, and the "Earth Environment Technology Development Plan" in 1989. The main purpose of the plan is to solve the problem of clean energy and accelerate the development and utilization of photovoltaic cells, fuel cells, hydrogen energy and geothermal energy to reduce existing energy consumption and carbon dioxide emissions. In addition, following the "Sunshine Project", Japan announced a 70,000 solar photovoltaic roof plan in 1997, and plans to install 7.6 million kilowatts of solar cells by 2010. Under the guidance of the "Earth Regeneration Program", Japan's photovoltaic technology has made considerable progress in the 1990s. By 2000, the combined annual production capacity of Kyoto Ceramics and Sharp Group reached 100,000 kilowatts, surpassing Germany's Siemens and ranking among the world's largest The first two; Japan’s automobile industry has generally begun the development of fuel cell vehicles. Toyota and Honda are scheduled to achieve marketization in the near future. In this way, Japan will also become a leading country in fuel cell vehicle technology like the United States, Germany and other countries.
The United States has proposed a development plan to gradually increase green power. Mainly through wind power generation, photovoltaic power generation, biomass energy power generation, etc. to achieve the goal. Among them, solar photovoltaic power generation is expected to account for about 15% of the increase in installed power generation in the United States by 2020, and the cumulative installed capacity will reach 36 million kilowatts, maintaining the United States in The world's leading position in the development and manufacturing of photovoltaic power generation technology. Experts estimate that by 2020, the global solar photovoltaic cells will exceed 70 million kilowatts, of which the United States will account for 50%. The basic strategy of the United States for the development of renewable energy technology is to occupy the commanding heights of technological development on the one hand, and to establish a broad market for the development of renewable energy. Under the guidance of this development strategy, the United States not only possesses a variety of high-tech renewable energy technology research and manufacturing capabilities, but also has a huge market share.
Solar energy diagram
Solar energy is the most important basic energy source among all kinds of renewable energy, and it is also the most abundant energy source available to mankind. The annual radiant energy projected by the sun onto the ground is as high as 1.05 x1018kWh (3.78 x 1024J), which is equivalent to 1.3 x 106billion tons of standard coal. According to the current solar mass consumption rate, it can be maintained for 6x1010years. So it can be said that it is "inexhaustible and inexhaustible" energy. However, how to rationally use solar energy and reduce the cost of development and conversion is an important issue facing the development of new energy.
Schematic diagram of wind energy
Wind energy is the use of wind turbines to convert wind energy into various forms of energy such as electrical energy, thermal energy, and mechanical energy, which are used for power generation, water lifting, navigation aids, refrigeration and heating. Wind power is the main development and utilization method. China’s total wind energy reserves are estimated to be 1.6x 109 kilowatts, ranking third in the world and have broad development prospects. Wind energy is a kind of natural energy. Because the direction and size of the wind are variable, its economy and practicality are determined by various factors such as the installation location, direction, and wind speed of the windmill.
Schematic diagram of nuclear power plant
There are many misunderstandings about nuclear power plants. In fact, nuclear power generation is a clean and efficient way to obtain energy. For nuclear fission, nuclear fuel is uranium, plutonium and other elements, and nuclear fusion fuel is deuterium and tritium. Some substances, such as thorium, are not nuclear fuels themselves, but they can be converted into nuclear fuels through nuclear reactions. We collectively refer to nuclear fuel and substances that can be converted into nuclear fuel as nuclear resources.
Hydrogen energy schematic diagram
Hydrogen is a secondary energy source, an ideal new energy-containing energy source. Although hydrogen is the most abundant element on the earth where humans live, there is very little natural hydrogen. Therefore, the hydrogen-containing material must be processed before hydrogen can be obtained. The most abundant hydrogen-containing substance is water, followed by various fossil fuels (coal, oil, natural gas) and various biomass. Hydrogen is not only a high-quality fuel, but also an important raw material and material in the petroleum, chemical, fertilizer, and metallurgical industries. The refining of petroleum and other fossil fuels requires hydrogen, such as the hydrogenation of hydrocarbons, the gasification of coal, the refining of heavy oil, etc.; the production of ammonia and methanol in the chemical industry also require hydrogen. Hydrogen is also used to reduce iron ore. Fuel cells made of hydrogen can directly generate electricity. Using fuel cell and hydrogen steam combined cycle power generation, its energy conversion efficiency will be much higher than existing thermal power plants.
With the advancement of hydrogen production technology and the perfection of hydrogen storage methods, hydrogen energy will show off on the energy stage of the 21st century.
Schematic diagram of geothermal energy
Geothermal refers to thermal energy resources from the ground. The earth we live in is a huge geothermal reservoir. Only a layer of 10 kilometers thick underground can store heat as much as 1.05 x 1026 joules, which is equivalent to the heat released by 9.95 × 1015 standard coal. Geothermal energy is widely used in many parts of the world. The old technology is still full of vitality, and the new technology has matured and is constantly improving. In terms of energy development and technology transfer, the potential for future development is considerable. Geothermal energy is naturally stored underground and is not affected by weather conditions. It can be used as a base load or can be provided for use as needed.
Schematic diagram of ocean energy
Ocean energy usually refers to the renewable energy contained in the ocean, mainly including tidal energy, wave energy, ocean current energy, sea temperature difference energy, sea salt difference energy, etc. Ocean energy is rich, widely distributed, clean and pollution-free, but low energy density, strong regionality, so development is difficult and has certain limitations. The main way of development and utilization is power generation, among which tidal power generation and small wave power generation technologies have been put into practical use. Wave power generation uses the kinetic energy of sea waves moving up and down. In 1910, Plessick of France invented a device that uses the vertical motion of sea waves to compress air to drive wind turbines to generate electricity, sending 1 kilowatt of electricity to the shore, creating a precedent for humans to convert ocean energy into electrical energy. At present, many types of wave generators of 60 to 450 kilowatts have been developed.
In addition, hydrogen energy is being researched and developed. Mainly use electrolysis, thermochemical, photoelectrochemical, plasma chemistry, etc. to prepare hydrogen, store it by compression, low-temperature liquefaction, or hydrogen storage alloy absorption, or directly use it as a fuel, or make a hydrogen fuel cell. For power generation, it can be used as fuel for various motor vehicles, aircraft, and household fuels; as well as biomass energy, it refers to the energy stored in biomass by plant chlorophyll converting solar energy into chemical energy. The current development and utilization technologies are mainly , Using thermochemical conversion technology to convert solid biomass into combustible gas, tar, etc., using biochemical conversion technology to convert biomass into biogas, alcohol, etc. under the fermentation of microorganisms, and compressing biomass through briquetting and fine honey molding technology Into high-density solid fuel, etc.
For China, vigorously developing and utilizing renewable energy will be one of the important strategic measures to optimize the energy structure, improve the environment, and promote sustainable economic and social development. At the beginning of 2006, the Chinese government has announced a new energy policy, which is an important part of the national economic development plan from 2006 to 2010. According to this policy, China will increase the use of renewable energy such as wind, solar and nuclear energy in the next five years. The National Development and Reform Commission also issued a notice on the "Guiding Catalogue for the Development of Renewable Energy Industry". With the great attention of the government, China's new energy industry has entered the fast lane and has achieved unprecedented success. However, with the changes in the economic situation in 2008, the sharp plunge in oil prices, and the gradual spread of the financial crisis, to a certain extent, the space for the development of the new energy industry was squeezed. Under the new situation, we should open up our thinking, get rid of the inertial thinking that only relies on conventional energy, and be brave to explore in order to make greater contributions to the development of China's new energy industry.