The Sun is an open fusion reactor, which converts around 600 million tons of hydrogen into helium (proton-proton chain) all the time while releasing a huge amount of solar energy sent to space.Out of a total of 3.8 × 1026 W which the Sun radiates in space, the Earth receives 1.75 × 1017 W. About 30 percent of the energy that Earth received, it reflects back into space, and our planet holds about 47 percent in the form of heat, about 23 percent goes to the process of water circulation in nature while the rest is “spent” on photosynthesis. Even fossil fuels are a kind of accumulated solar energy: oil, gas, coal.
Earth adds more energy from the Sun in just one hour than the human population uses in one year. Total solar energy absorbed in the Earth’s atmosphere, oceans and land amount to about 3,850,000 EJ per year. The amount of solar energy that comes to the surface of the planet is enormous so that in one year it is twice as high as all non-renewable energy resources of the Earth.
The energy of solar radiation is more than enough to meet the growing energy demands of the world. Within one year, solar energy that reaches the earth 10,000 times is greater than the energy necessary to meet the needs of the entire population of our planet. A large part of absorption surface could be located on roofs and walls of buildings, so it would not require an additional surface on the ground.
In residential buildings, there are two types of solar thermal energy systems: those used exclusively for water heating and those who provide hot water and heat for the house. Solar thermal energy systems for water heating are designed so that they are fully responsible for water heating in the warmer half of the year. This means that about 60% of the required hot water can be generated each year by solar thermal energy systems.Typically, solar energy can provide 10 to 30% of the total energy needs of the building for heating, not just water but living space also. There are also special solar houses that receive 50 to 100% of total solar heating.
Solar thermal energy
Solar thermal energy is the electricity source generated by converting solar energy into heat. As the amount of energy that falls on the surface of the earth is extremely high, by constructing such power plants, in the sunny areas, energy could be easily distributed to a large number of consumers. Solar power plants make it possible to generate heat energy very simply and efficiently, providing electricity during the dark.