Power plants can produce electricity because generators can convert other forms of energy into electrical energy. Hydroelectric power plants rely on the gravitational potential energy of water to produce electricity. The drop in the Three Gorges Power Station is approximately 113 meters. When water falls from such a high position, much of the reduced gravitational potential energy is converted into electrical energy.
Raindrops fall from the sky, and the height of the fall is generally more than a few hundred meters, and some will fall thousands of meters. Is it possible to produce electricity by relying on falling raindrops? You can think of the paragraph about a group of doctors calculating the speed of falling raindrops. If calculated based on free fall motion, the speed of raindropsfalling to the ground is very high. For example, if you fall to the ground from a height of 1,000 meters, the speed will reach 140 meters per second, which is enough to harm people. But in fact, people caught in the rain will not feel hurt by raindrops, because the speed at which raindrops fall on the ground is not very fast at all. The speed of raindrops falling to the ground is related to the mass of the raindrops. The speed of small-mass raindrops reaching the ground is less than 1 meter per second, and the speed of large-mass raindrops generally does not exceed 10 meters per second. second. Most of the mechanical energy of the raindrops has been converted to internal energy by friction with the air in the air, and there is not much mechanical energy left in the raindrops.
Most of the mechanical energy of raindrops is convertedin internal energy. Isn't it possible to use internal energy to produce electricity? Thermal power plants use the thermal energy released by burning coal to drive the rotor and then convert the mechanical energy into electrical energy. However, thermal power plants need heat engines capable of converting internal energy into mechanical energy. Internal energy is difficult to use because it involves directionality of energy conversion. Mechanical energy can be easily converted into internal energy, but internal energy cannot be easily converted into mechanical energy. The conversion rate of internal energy into mechanical energy will never reach 100% and is related to the temperature of the high temperature heat source and the low temperature heat source. Like raindrops falling from high altitudes, their temperature changes are very small. It is not worthit is worth installing a thermal machine between the sky and the earth to convert the internal energy of the raindrops into mechanical energy and then into electrical energy.