For a long period of time already, the micro hydropower plants are known as a source of relatively inexpensive way of producing electric energy.
On the market there are provided different systems for the production of energy from the water, including river or sea water.
The wind power plans and the wind parks are widely used by many countries for the production of electric energy. They are built in areas with a constant air flow.
To build a wind park are required enough free space and a large initial investment.