Sustainable technologies are those technologies that incorporate the inexhaustible sources of available energy in nature to be channelled for productive purposes for the benefit of mankind. They are essentially clean technologies and supportive of the environment and habitat. The phenomenal development of power and energy through conventional sources such as petroleum, coal and atomic energy has brought about a sea of change in the living conditions of mankind. But exploiting nature without regard for the environment will produce disastrous results. For this reason, we have to think of soft technologies that will keep our environment clean and unaffected by pollution produced due to the reckless use of natural resources that go beyond our legitimate requirements. When we speak of sustainable technology, these should conform to certain aspects of health related activities that do not bring with them the destruction of mankind. These are technologies preferably generated at the place of utilisation and quite close to the energy sources required by mankind. From this definition it follows that rural technologies are sustainable technologies that are obtained in the rural context. Thus they are windpower, solar energy and bio-gas, which together provide the energy sources required to produce power and which are utilised at the place where they are generated.
