Any form of energy which does not involve any significant negative impact on the environment can be termed as Green Energy. In other words the energy which can be generated and/or consumed without any negative effect on the ecological balance is called the green energy.
The electrical energy or the electricity produced from solar energy, geothermal energy, biomass, wind, and water sources (hydroelectricity) is known as Green Power.
The technology of deriving energy from sun, wind and biomass comes under the second generation technologies and among all the solar energy technology is becoming the first choice in India.
Solar energy technology can be subdivided in to two categories:
- Active Solar Technology and
- Passive Solar Technology
Active Solar Technology
Active Solar Technology is used to convert the solar energy in to heat or electricity by using mechanical, electrical or electronic equipment while the Passive Solar Technology does not involve use of the electrical or mechanical equipment.
|Passive solar building design(source: wikipedia)|
Passive solar technology makes use of the inherent thermodynamic properties of the system or materials and does not require external energy sources to operate. If a building is designed using passive solar technique its windows, walls, and floors are designed to collect, store, and provide the solar energy in winters and reject the same in summers.