Co-generation

The UK could meet 5% of its heat requirements and save some 10 million tonnes of CO₂ by fitting heat capture technology to just a few of the country’s biggest power stations such as Kingsnorth and Drax, according to a report.

Heat makes up just under half of the UK’s total primary energy consumption – more than used in electricity production or transport – and mainly comes from gas.

However, traditional coal and nuclear power stations are only around 35% efficient, meaning that a huge amount of generated heat is wasted. For every 1000 MW of electricity generated, 2000 MW of heat just goes up the chimney of cooling towers.

According to a study by the University of Southampton and the Institution of Civil Engineers (ICE), heat capture technology could be fitted to the UK’s power stations and new housing developments should be designed with local combined heat and power (CHP) plants.

“The truth is, that if half of the heat lost during electricity production could be captured it would meet 25% of the UK’s heat demand, dramatically reducing energy consumption, cutting costs and carbon emissions,” says Keith Tovey of the ICE’s energy panel.

While this level of capture and re-use is impractical because many power stations are located far from centres of population, some of the UK’s largest power stations – namely Kingsnorth and Drax – are near enough to make retrofitting heat capture technology potentially worthwhile.

Although installing CHP onto power plants reduces electricity production slightly, it increases overall fuel efficiency to around 80%.
“In the longer term we need to consider the potentially huge benefits that decentralised CHP could bring to the UK,” says Tovey.

“With the current generation of thermal power stations coming to the end of their lifespan, there is a real opportunity to vastly improve the efficiency of our energy sector and drastically lower its carbon footprint.”

Decentralised CHP and district heating has been applied very successfully in Scandinavia and some parts of Europe, where smaller power stations are located close to centres of population.

“It’s true that delivering decentralised CHP across the UK would require significant new infrastructure and a large reorganisation of the sector, but if we are to guarantee security of supply, whilst meeting tough carbon targets, radical change may be what is needed,” says Tovey.

For further information:
www.ice.org.uk/knowledge/document_details.asp?Docu_id=2302&faculty
www.ice.org.uk/
www.soton.ac.uk/
www.eon-uk.com/generation/kingsnorth.aspx
www.draxpower.com/