①Environmental impact of conventional energy
The development and utilization of any kind of energy will have a certain impact on the environment. The environmental problems caused by conventional energy sources represented by fossil fuels are particularly serious, mainly in the following aspects.
Ⅰ. Air pollution
The use of fossil fuels produces harmful gases such as carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen oxides (NOx), which not only cause the destruction of the ecosystem, but also directly harm human health. In many countries and regions, the direct and indirect losses caused by air pollution have been quite serious. For example, the EU exceeds 10 billion U.S. dollars each year, and China is as high as 12 billion yuan. The factory pollutes the atmosphere with a large amount of exhaust gas as shown in Figure 1. The urban smog is shown in Figure 2.
Ⅱ. Greenhouse effect
When the concentration of CO2 in the atmosphere doubles, the average temperature of the earth’s surface will rise by 1.5~3℃, and it may rise by 6~8℃ in the polar regions. As a result, the sea level may rise by 20~140cm, which will cause serious economic problems for many countries. social influence. Due to the burning of a large amount of fossil fuels, the concentration of CO2 in the atmosphere has continued to increase. The CO2 content per 1 million atmospheric units was 280 units before the industrial revolution and 349 units in 1988, and it is even higher now. Figure 3 shows the carbon emissions of global fossil fuel combustion. The schematic diagram of the greenhouse effect is shown in Figure 4.
Ⅲ. Acid rain
A large amount of SO2, NOx and other pollutants produced by the burning of fossil fuels are transported through the atmosphere, forming large areas of acid rain under certain conditions, changing the nature of the soil covered by acid rain, harming crops and forest ecosystems, changing the acidity of lakes and reservoirs, and destroying aquatic ecology The system corrodes materials and causes major economic losses. Acid rain has also led to regional climate changes, causing incalculable consequences. The damage to buildings and forests is shown in Figure 5 and Figure 6.
If you consider the adverse effects of energy extraction, transportation and processing, the loss will be even more serious. On average, 15-30 people are injured for every 10,000 tons of coal mined, which may cause 2000m2 of land to collapse. On average, more than 200 square kilometers of land collapse every year in the world.
Although the use of nuclear energy does not produce the above-mentioned pollutants, it also has the problem of nuclear waste. The use of nuclear energy worldwide will generate thousands of tons of nuclear waste. If it cannot be handled properly, the hazard or risk of radioactivity will last for hundreds of years.
②World energy and environmental issues
The world population has increased by more than three times from 1.6 billion in 1900 to 7 billion at present, while the statistical energy consumption has increased by 16 times. This shows that human beings are increasingly dependent on energy.
The primary energy consumption and consumption structure of each continent in the world in 2015 are shown in Figure 7, and the primary energy consumption and consumption structure of major energy countries are shown in Figure 8.
It can be seen that at present, fossil energy sources such as oil, coal, and natural gas still account for a high proportion of the world’s energy consumption structure, with a total of 87%. If there is no full development of new alternative energy sources, based on current consumption estimates, mankind will face a new energy crisis in the 21st century. Moreover, the extensive use of fossil fuels by humans has caused increasingly serious environmental pollution, and the ecological balance has been ruined, directly endangering the survival and development of mankind.
The UN World Commission on Environment and Development, headed by Mrs. Brundtland, the former Prime Minister of Norway, has completed the survey report “Our Common Future” and put forward the concept of sustainable development. This concept and its concept were recognized by more than 100 countries in the world at the 1992 United Nations Conference on Environment and Development. Sustainable development is “development that meets the needs of contemporary people without compromising the ability of future generations to meet their needs.”