Greenpeace : Ultra-Efficient Combined Heat + Power Stations

ALEX KIRBY

Decentralised Energy

The single biggest use of energy in the UK is not for transport or generating electricity, but for heat to warm our homes and offices and for industry. So tackling climate change needs to save some of the heat we all use, apart from reducing or eliminating the fossil fuel used in power stations to generate our electricity. And there is a solution. We can replace the current inefficient energy system with one that will do far more to reduce carbon emissions and ensure energy security: a combination of renewable energy, energy efficiency, and combined heat and power.

Renewables
Our windswept islands have more than enough wind, wave and tidal power potential to meet all of our energy needs many times over. Between them they could deliver a substantial portion of the UK's share of the EU 20% of energy from renewables by 2020 target.

Efficiency
Inefficient buildings and appliances mean we waste more than eight times the amount of energy produced by all UK nuclear power stations combined - every year. Simple steps - as simple as not over-filling kettles - can cut demand for both heat and power, lowering our need for gas imports and saving billions a year.

Combined heat and power (CHP)
The UK’s electricity system is incredibly wasteful, with most of that wastage occurring before the electricity even reaches our homes. Power stations waste two-thirds of the energy they generate – enough to warm every building in the UK, and to provide the hot water too. If smaller, more efficient, power stations are sited near towns and cities or on industrial sites, this heat could be captured and used in nearby homes or factories. CHP is perfect for heating and powering communities. The plants can be small, quiet and unobtrusive. Piping heat from an ultra-efficient CHP unit within a town cuts heating bills and fuel poverty and provides a local, secure source of heat and electricity.

Southampton's district energy scheme, one of the largest commercially-developed community networks in the UK, uses geothermal energy (generated by heat stored beneath the Earth's surface) to provide heating and cooling to over a thousand homes, several large office buildings, a hospital, a university, and one of Europe's largest shopping complexes.

The network cost £7m to develop and now sells 40GWh of heat, 22GWh of electricity and 8GWh of cooling every year, with 11 kilometres of heating and cooling pipes. It saves over 12,000 tonnes of carbon emissions annually and is 85% efficient (compared with an average efficiency of about 38% for centralised power stations). This high efficiency level won the scheme a Queen's Award for Sustainable Development in 2001 and a National Energy Efficiency Award in 2006.