This snapshot, taken on 02/09/2009, shows web content selected for preservation by The National Archives. External links, forms and search boxes may not work in archived websites.
Large-scale hydroelectric schemes are usually built in remote areas away from centres of population. They can be a valuable source of employment to the area during construction and operation.
The creation of a reservoir can offer recreational and tourist opportunities.
Small-scale hydroelectric schemes in particular are quiet and visually unobtrusive. Large-scale hydroelectric projects cause an increase in traffic during the construction phase, which can be long and very noisy.
Most hydropower schemes can add positively to the visual environment, although some dams and eroded reservoir shorelines can have a negative visual impact.
For houses with no mains connection, but with access to a micro-hydro site, a good hydroelectric system can generate a steady, reliable electricity supply at a lower cost than other renewable technologies. Though still quite high, total system costs are often less than the cost of a grid connection, with no electricity bills to follow. Micro-hydro schemes have proved useful for powering remote domestic communities and as part of development projects in less developed countries.
Most participants in a DTI renewable energy survey had heard of hydroelectric power but had little understanding of how it worked. Hydroelectric power was accepted as an established method of supplying energy. There were no negative views on this source of energy and some considered hydroelectric schemes as tourist attractions. For instance, the Pitlochry hydropower plant is one of the top 10 visitor attractions in Scotland. Some referred to watermills producing energy and the fact that this method of generating power has historic roots. Participants were concerned about the social impact of hydroelectric schemes, particularly if such schemes required the flooding of valleys, and were opposed to hydroelectric schemes under such circumstances.
Hydroelectric power schemes need an abstraction licence from the Environment Agency. Under this licence, the effect of the turbine on a river’s ecosystem will be investigated. The river’s ecology is protected by restricting the proportion of the total flow diverted through the turbine. Large hydroelectric power schemes may include fish ladders to allow migrating salmon and sea trout to pass into the upper river to spawn.
With small-scale hydroelectric schemes, the embodied energy of a scheme (the energy used in the manufacture of the components and construction) is typically equalled by the energy generated by the scheme within nine months of commissioning.
Emissions are not a problem on small-scale schemes. In larger schemes that have involved flooding, some carbon dioxide emissions may come from decaying vegetation in the short term.
Turbines can produce some noise but this can be mitigated relatively easily.
