The wind is a theoretically inexhaustible energy source. However, the proportion of this energy that can be harnessed to provide electricity is limited by constraints on constructing and siting wind turbines and the cost of the infrastructure needed. It is thought that, taking various limitations into account, with unlimited spending, the UK could potentially generate a maximum of 83 billion kilowatt-hours per year (kWh/year) from onshore wind turbines and 406 billion kWh/year from offshore wind turbines. In 2009, the UK's total demand for electricity was around 379 billion kWh.
However, for onshore wind to fulfil just 10% of the UK's electricity needs, between 80,000 and 120,000 hectares of land – between 0.3% and 0.5% of the land in the UK – would need to be covered with wind turbines. Furthermore, only a limited number of sites in the UK are windy enough to make installing wind turbines worthwhile. Reservations about the noise and visual impact of wind turbines are a significant barrier to extensive development, and contribute to planning issues.
In 2009, just one in four planning permission applications for UK onshore wind farms were approved at the first opportunity. Even once planning permission is secured, the wait for building consent in the UK averages 26 months. The UK's manufacturing sector has so far been cautious about getting involved with renewable energy. This has limited the speed at which new wind farms can be installed, and has contributed to increased costs, because many of the necessary components have to be imported.
These are the quantity of supply challenges facing wind. Read about the possible solutions.