1. In the lecture on Hydroelectric Power and Wind Generation, advantages and disadvantages of hydro and wind generation are discussed. Using your own research, discuss the advantages and disadvantages of: (a) coal-based generation, (b) natural-gas combined cycle generation, and (c) nuclear power generation based on their environmental and production efficiency. (a) coal-based generation Advantages：1. It has large reserves. Many countries such as China, India and Russia have a large amount of coal. So it is enough for us to use coal-based generation for next 400 years. 2. It is a full-time energy resource. Unlike solar, tide or wind, which are restricted by the weather conditions, coal-based generation can work every minute to produce energy. Disadvantages: 1. Non-renewable resource. Like other fossil fuels, it will eventually become depleted. 2. Coals contain a high level of toxic emissions. It produces polluting gases, such as sulfur dioxide, which exacerbate the formation of acid rain and warm global temperature. The carbon dioxide produced by burning coal is also one of the main causes of global warming. (b) natural-gas combined cycle generation Advantages: 1. Environmental friendly.Burning clean fuel natural gas is almost dust-free (PM2.5), sulfur dioxide emissions are extremely low, nitrogen oxide emissions are very low after low-nitrogen burners and flue gas devices, and greenhouse gas emissions such as carbon dioxide are also about half of coal-fired power plants. The environmental protection advantage is very prominent. 2. Thermodynamic advantages of gas-fired power generation. Gas-fired power generation conventionally uses a gas-steam combined cycle method, which is due to high cycle heat efficiency and low heat generation rate. At present, the thermal efficiency of power generation in modern natural gas installations is as high as 58% to 60%, which is much higher than the thermal efficiency of coal-fired power generation. Disadvantages; The price of natural gas is high and insufficient gas raw materials in some countries. For example, almost all natural gas companies in China are at a loss, and at least 30% of natural gas is imported. (c) Nuclear power generation. Advantages: 1. Nuclear power generation does not emit a huge amount of pollutants into the atmosphere like fossil fuel power generation, so it does not pollute the air and does not increase the greenhouse effect.
2. The energy density of nuclear fuel is several million times higher than that of fossil fuels. The fuel used in nuclear power plants is small in size and convenient for transportation and storage. Among the costs of nuclear power generation, the