Wind energy is the use of airflow through wind turbines to generate mechanical energy for electrical energy. Wind energy, as an alternative to burning fossil fuels, is abundant, renewable, widely distributed, clean, does not produce greenhouse gas emissions during operation, does not consume water and uses little soil. The net effects on the environment are much less problematic than those of non-renewable energy sources.
Wind farms consist of many individual wind turbines that are connected to the electric power transmission network. Wind on land is an economical source of electric power, competitive with or in many places cheaper than coal or gas plants Offshore wind is more stable and stronger than land, and offshore farms have less visual impact , but construction and maintenance costs are considerably higher. Small wind farms on land can power some power in the grid or provide electrical power to isolated locations outside the grid.
Wind power offers variable power that is very consistent from year to year, but has a significant variation in shorter time scales. It is therefore used in conjunction with other sources of electrical energy to provide a reliable supply. As the share of wind power in a region increases, there may be a need to improve the grid and a lower capacity to supplant conventional production. Energy management techniques, such as over capacity, geographically distributed turbines, distributable sources of support, sufficient hydropower, export and import of energy to neighboring areas or reduced demand when wind power production is low can overcome in many cases these problems. In addition, the weather forecast allows the electric power grid to prepare for the predictable variations in production that occur.