There are three main types of hydropower schemes
- Storage schemes - where a dam impounds water in a reservoir that feeds the turbine and generator.
- Pumped storage schemes - which incorporate two reservoirs. At times of low demand, generally at night, electricity is used to pump water from the lower to the upper reservoir. This is released through turbines to generate electricity when demand is high.
- Run of river schemes - use the natural flow of a river and divert water to a remote powerhouse containing the turbine and generator to generate electricity.
What is a sustainable hydropower scheme?
A sustainable hydropower scheme builds environmental protection into the location, design and operation of the scheme. Key features include:
- a turbine and screening arrangement that protects fish
- maintaining or improving fish passage within a water body
- sufficient flow in any depleted reach to maintain or improve the ecology of the water body so it is more likely to comply with relevant directives
- a design that avoids impairing flood management structures or adversely affecting land drainage
Protecting the environment
Where schemes will not be compliant with environmental or other legislation by for example, preventing the passage of migratory fish or increasing flood risk, we will not permit their development.
Hydropower schemes can have adverse impact on the local environment, especially fish populations and other aspects of river ecology. Fish can be harmed if they pass through a turbine and some hydropower schemes can lead to reduced flows in rivers, increase flood risk or adversely affect land drainage.
We’ve published good practice guidance for hydropower schemes. This gives guidance on what developers should do to comply with environmental and other legislation. We’ll be revising this guidance in 2013.
Hydropower currently produces 1.3 per cent of the electricity consumed in the UK, mostly from large scale schemes in Scotland. The contribution from hydropower in England and Wales is currently less than 0.1 per cent.
The Department for Energy and Climate Change estimates the potential small scale hydropower resource in England and Wales could be up to 0.3 per cent of current electricity supply. This could make a small, but useful, contribution to our future energy supply.
Hydropower applications (2009 - 2012)
There are currently about 500 hydropower schemes consented in England and Wales. Not all of these have been developed.
Applications over the last four years:
In 2009 we approved 29 new schemes (24 in England, 5 in Wales) and received 14 pre-applications
In 2010 we approved 57 new schemes (44 in England, 13 in Wales) and received 130 pre-applications
In 2011 we approved 63 new schemes (44 in England and 19 in Wales) and received 203 pre-applications
In 2012 we approved 68 new schemes (33 in England and 35 in Wales) and received 210 pre-applications
Number of schemes refused
In the four years we refused nine schemes - eight in England and one in Wales.