Solar+heating+-+John

​ Solar Heating

What is solar energy?
Solar energy, power from the sun, is free and inexhaustible. By the time it reaches the earth's surface, some of the energy bounces back to the universe and only some is absorbed by the earth. The energy in sunlight has fallen to about 1,000 watts per square meter. If you average this over the entire surface of the earth, each day, on average, a square meter collects 4.2 kilowatt-hours of energy. ​

= How does it work? =     ← Solar Collector

==== Solar collector (also known as Solar Thermal Panel) is the key component of active solar-heating systems. Solar collectors gather the sun's energy, transform its radiation into heat, then transfer that heat to water, solar fluid, or air. ====

Process of Heating Water:
Most solar heating systems are used to heat water for washing and showering. The way the system is typically designed and installed is to have an array of solar collector panels on the roof of your home. These are then connected to a hot water tank and a fluid is circulated around the solar panels and the hot water tank. As the fluid passes through the panels, the suns energy heats the fluid up to a high temperature. However, the fluid that is circulated through your solar panel is used to heat the water in your hot water tank, it is not used for washing and showering. These are not passive systems. They will have sensors to detect when the sun is hot enough to heat the fluid and will then start the pump working. Once the solar energy is collected by solar collectors, some of energy is stored in one place to use when there is no sun ( night, raining day)

Today they are used in:
 * Water heating system
 * Electric power station
 * House furniture (lamp)

In future they will be used in:
 * Transportation (car, airplane)
 * Underground Cultivation

// Advantages of Solar Heating: //

 * Harmless to environment
 * Inexhaustible
 * You don't have to pay more money once after you set up

// Disadvantages of Solar Heating: //

 * Affected by weather
 * Expansive to set up
 * Need big space to set up

Energy Changes involved: Light Energy -> Thermal Energy The sunlight is collected and the energy is to heat up water.
 * Solar water heating systems cost between $1,500 to $3,000. Although this is a much higher up front cost than a traditional water heater, those using solar power can see savings on their electric bill by 50 to 80 percent.

Examples:
▼ e
 * Heating house (water, floor)
 * small furniture like lamp