Main Menu
- Other links
- Sections
- About
This snapshot, taken on 02/10/2007, shows web content selected for preservation by The National Archives. External links, forms and search boxes may not work in archived websites.
The UK is currently slightly behind the course needed to meet this aim. However, both onshore and offshore wind power can deliver almost all of the required growth in renewable energy to meet the 2010 target of 10 per cent. It is likely that wind power will continue to be the dominant renewable technology to help reach the 2020 aspirational target. However, there are a number of important factors, such as regulatory, planning and grid/network connection issues, that must also be addressed and the BERR is working hard to make sure that these are resolved in a timely fashion.
In 2005, renewable energy sources contributed 4.2 per cent of total UK electricity supply. This is based on the international definition of renewable energy sources and excludes the use of non-biodegradable waste.
Biomass. The UK currently generates about 1.6 per cent of its electricity from biomass, which includes electricity generation from landfill gas, the biodegradable portion of municipal solid waste, and co-firing of biomass.
The efficiency of renewable energy technologies can vary markedly. For example, the efficiency with which a hydro plant converts the potential energy of running water into electrical energy is around 90 per cent, but the efficiency with which a commercial solar cell converts solar energy into electrical energy is currently only around 10 to 15 per cent. However, comparing the efficiency of renewable energy technologies with others, such as gas turbines or coal plants, can be misleading because for the majority of renewable technologies the fuel is free. A more useful comparison is the cost to generate a unit of energy.
With the exception of large hydropower plants, most renewable energy is not as economic as fossil fuel generation – although landfill gas and onshore wind in favourable locations are becoming reasonably close. However, there is significant scope for cost reduction. For example, wind costs have declined by over 80 per cent in the last two decades, with room for further improvement.
Many renewable technologies are expected to become cost-competitive with fossil fuels in the next 10 to 20 years, especially as fossil fuel prices rise as reserves begin to decline. Renewable energy’s competitiveness will also be enhanced by policies that begin to incorporate the environmental and social costs of using fossil fuels, which are not currently reflected in their price (such as global warming, acid rain, air pollution and its effect on human health, etc). Some examples of these policies include the existing Climate Change Levy and the forthcoming EU Emissions Trading Scheme, due to start in January 2005.
Properly designed combustion chambers used for the burning of biomass will minimise emissions of particulates and poly-aromatic hydrocarbons (PAHs) to the atmosphere. The atmospheric emissions from a 1-megawatt woodchip-fired biomass boiler used to provide district heating are equivalent to the emissions produced by a single domestic coal fire. Anaerobic digestion treatment stabilises slurries, significantly reducing odours. A properly managed anaerobic digestion scheme will also contain the intense nutrients found in animal slurries and food residues which can otherwise leach out in high concentrations and pollute soil and water courses.
Geothermal power, using high temperature grades of heat, is only relevant to certain geographical and geologically suitable areas. It requires the presence of ‘hot rocks’ that are fractured and relatively near to the surface, and that can be tapped into by drilling. The Weardale Granite, which underlies much of the North Pennines, is a good example of fractured hot rock. Advances in drilling technology have increased the interest in this area.
There are similar areas of hot rock underneath parts of southern England and Derbyshire, but the only area where these have been successfully exploited to provide power is in Southampton, where geothermal hot water provides energy for a combined heat and power system, administered by the City Council. The economics of this type of geothermal energy mean that, compared with countries such as New Zealand or Iceland, the UK is unlikely to exploit it significantly.
Ground-source heat pumps, which exploit lower grades of thermal energy (10–20°C) just beneath the surface, have much greater potential in the UK, and can provide a highly efficient method of heating.
Economic and environmentally sensitive considerations mean that there is very little scope for more large-scale hydroelectric schemes. Only one new scheme at Glendoe in Scotland, due to begin construction in 2005, has been given planning permission. However, small-scale and off-grid micro hydroelectric schemes offer some potential for further expansion.
Fuel cell technology is mainly used for powering vehicles at present. However, much research is under way and some combined heat and power (CHP) schemes are in operation (see Hydrogen case studies), aimed at providing power for everything from individual houses to large office buildings. Large stationary hydrogen fuel cells could also be used to provide energy storage, helping to reduce the effects of intermittency from renewables. Small-scale portable fuel cells are also starting to be developed for use in devices such as laptops and mobile phones.
Not as much as the available potential (see Facts and figures). Total installed capacity amounts to only 1.25 megawatts spread between two different devices (see Wave case studies). These are still at the prototype-testing phase, but if they are successful they will offer the potential to tap the UK’s excellent wave energy resource.
No. Aside from passive solar designs, which use principles like south-facing windows to make the most of sunlight, there are two main ways of using solar energy. The first is using active solar heating to heat water. This can be used in applications such as swimming pools, individual houses and office blocks. The second way is via solar photovoltaic (PV) panels. These convert sunlight into electricity and can be used in anything from powering calculators to phone booths and houses. Larger-scale applications of solar PV are generally connected to the main electricity grid so any surplus power can be sold back to it.
Although there is some localised opposition to wind farm developments, public surveys consistently demonstrate that a clear majority of the general public are in favour of wind energy. The same surveys have shown that people living near wind farms are in general less opposed than those who have no first-hand experience. This indicates that many opponents’ fears are unfounded. Similar numbers also do not believe that wind farms spoil the scenery or cause noise nuisance.