Have questions around power generation? Start here for simple answers and dive deeper for additional insights.
Power generation is complicated but let’s try to keep it simple.
Power generation is a term used to describe electricity production using different types of technology—some, such as steam boilers, are more than a hundred years old and others, such as wind turbines, are newer. Actually, steam boilers and windmills are a lot older. They were initially invented to move machinery and crush grain and they still do but now they’re mostly used to make electricity.
最多power generating equipment通过在交流发电机中旋转机制来产生电力。如何制作机制旋转取决于使用了哪种技术。
交流发电机非常像电动机。电动机使用电力旋转转子。在交流发电机中，这是相反的 - 而不是使用电力创造运动，而是交流发动机使用运动来产生电力。实际上，许多电动机可以用作临时交流发电机。
交流发电机are made up of two parts: a stator and a rotor. The rotor spins inside the alternator and is designed to create a magnetic field. The stator is essentially a box made up of many copper windings wrapped around a hollow iron core. When the rotor spins inside the stator, its magnetic field rotates too, and that rotation create an electrical current inside the stator’s windings. That electrical current is collected and sent to the power grid.
发电机是围绕往复式发动机和交流发电机建造的小型，独立的发电厂。发动机和交流发电机通常组合成单个外壳，该外壳可以像拖拉机拖车一样大，或者与手提箱一样小，具体取决于需要多少电力。具有适合不同燃料的发动机的发电机可用 - 柴油，汽油，生物燃料，天然气等。
较大的发电机用于多种applications and industries。它们可以用作主要力量或待机力。例如，部署在没有可靠电网的地区，例如，通常依靠基本发电机来满足其所有电力需求。在任何时间都无法接受的建筑物中，安装备用发电机以在停电时提供电力。Data centersand hospitals are examples of buildings that require standby generators.
Types of power plants
What are solar power plants?
Solar electricity is made in photovoltaic panels that use sunlight to activate the silicon cells that they contain. When photons from the sun hit the silicon cells, they knock out electrons from the atoms present in the silicon. The cells are designed in such a way that electrons can only travel in one direction. So, when the cell’s electron collector is connected to an electrical load, electrons line up to travel out of the cell and into the electrical load. In other words, an electrical current is generated.
Solar energy technology has expanded to concentrated solar plants with steam turbines. In some configurations, mirrors are set around a tower and the reflection is aimed at a receptor at the top of the tower. Think of it as using a magnifying glass to concentrate the sun’s rays to start a fire. The top of the tower has a steam boiler from which hot steam is piped down to a ground-level steam turbine.
What are gas-fired power plants?
在gas-fired power plants that rely on a gas turbine, the process goes like this:
Jet engines operate in a very similar way, the difference being that the torque spins fan blades and propels the jet.
What are diesel-fired power plants?
Diesel-fired发电厂相对较小的我n power generation capacity compared to other power plants. These power plants often use the reciprocating engines for power generation. These reciprocating engines are just like a car’s engine:
- A piston rises and lowers as the air and fuel mixture combusts.
- The piston is connected to a crank shaft that produces a spinning motion.
Reciprocating engine-based power plants can actually burn a variety of fuels, including natural gas, heavy oil and more.
What are coal-fired power plants?
在coal-fired power plants the process goes like this:
- A fuel source is fired-up to heat water in a boiler.
- The heated water in the boiler turns to steam.
在核电厂, the process is the same with steam turbines, but water is boiled by the heat coming from the fission of uranium atoms, rather than the combustion of fuel.
Nuclear power plants house one or more reactors where nuclear fission takes place. Large uranium atoms are split apart to form smaller atoms, releasing a tremendous amount of energy in the process. The uranium is brought to the reactor in the form of uranium oxide pellets stacked together in sealed metal tubes called fuel rods. The fuel rods are inserted into a large vessel filled with water and pressurized—the reactor vessel. Once the nuclear fission is initiated, the fuel rods heat the water present in the reactor vessel, creating steam. This steam then goes on to spin a steam turbine and electric alternator set, creating electricity.
No fossil fuel is involved at any point in the process, so nuclear power plants don’t generate any carbon emissions. What they do generate however is lots of highly radioactive spent fuel rods, which nobody really knows what to do with.
There are about 94 nuclear reactors installed at 57 power plants in the United States and about 450 reactors worldwide, as of 2021.
Steam turbines can piggy-back on gas turbines to make a “combined-cycle” plant that uses the waste heat from the gas turbine to make steam. The gas turbine’s exhaust heat now produces additional electricity. This is why combined-cycle power plants have better efficiency and higher output than simple-cycle power plants.
Benefits of different power generation technologies
Each type of power plant and power generation technology comes with advantages and drawbacks.
Nuclear power plants produce lots of electricity with very little fuel and almost no emissions, but nuclear waste is a major problem that has yet to be resolved.
Gas turbines generate less emissions and are more efficient than most steam turbine-based power plants but tend to be expensive to maintain. They also run best on natural gas, which is not available everywhere.
Reciprocating engines have great flexibility: they have a quick-start and quick-stop ability, and they can run on a variety of fuels, are very efficient, and relatively low cost to build and maintain.
风力涡轮机和太阳能电池板不产生直接排放，不需要燃料，但是它们的输出是可变的，有时是不可预测的 - 在无风的一天中，风电场不会产生很多电力。
As the global desire for cleaner power generation and reduced emissions for future generations increases, the shift to clean, renewable energy continues to grow. With so many wind and solar farms on the power grid, it is important to have enough flexible power plants that can start and stop quickly to compensate for the variability of wind and solar power. Gas turbines and reciprocating engines are well suited for this and a popular option among power companies.
All power generation systems and power plants work by converting energy that is available in one form or another into electricity.
太阳能电池板和风电场转换了其环境中的能量 - 纵火和风能。同样，水力发电植物提取了堵墙的水的势能，或河流中存在的动能以发电。风，阳光和水的能量被认为是可再生的，因为它的来源不断补充，即使其可用性取决于天气条件。