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BEM38 Sustainable Energy for Buildings. emerging sustainable energy technologies. clean coal-fuelled power generation. Ferrybridge Power Station (Eric De Mare). Oil, coal and natural gas dominate the world’s primary energy market and will continue to do so for the foreseeable future.
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BEM38 Sustainable Energy for Buildings emerging sustainable energy technologies
clean coal-fuelled power generation Ferrybridge Power Station (Eric De Mare)
Oil, coal and natural gas dominate the world’s primary energy market and will continue to do so for the foreseeable future. Barely 10% of global fossil fuel reserves have already been consumed. Coal is perceived as environmentally unfriendly, producing relatively large amounts of CO2 and SO2 when burnt.
For coal to continue to drive power generation across the globe, technology must continue to be developed to reduce coal plant emissions to near zero.
While the demand for the coal across Europe is falling, elsewhere – notably USA, India and China – the demand for coal is increasing. Coal is the cheapest fossil fuel, the easiest to extract and by far the most abundant. Coal will continue to be a primary energy source for decades, possibly for centuries. Implementing clean coal burning technologies is essential to maintain CO2 reduction targets.
Three strategies for reducing emissions from fossil fuel power generation:- (a) increase energy efficiency of thermal cycle (b) use a less carbon intensive source (c) capture and storage of CO2
Increasing the energy efficiency of the thermal cycle Rankine cycle + Brayton cycle = Combined cycle Combined cycle fed with superheated high pressure air and gasified coal = IGCC Use pulverised coal in an IGCC plant
Capture and storage of CO2 pre combustion capture oxy-fuel combustion post combustion capture
Pre combustion capture coal gasification + combined cycle power generation = IGCC
Pre combustion capture underground coal gasification
Oxy-fuel combustion Coal combustion occurs in an O2 enriched environment, producing a flue gas comprised mainly of CO2 and water. The water is easily separated by condensation and the CO2 is ready for sequestration.
Post combustion capture Carbon capture and storage, also known as CCS or carbon sequestration, describes a family of technologies designed to tackle global warming by capturing CO2 – from coal-fired power stations in this case – and permanently storing it underground.
Post combustion capture source: http://www.wri.org/project/carbon-dioxide-capture-storage
Conclusions Experts have divergent views on the economic and technical feasibility of commercial-scale CCS. Up to 40% of a power station's energy could end up being used to run the CCS scrubbing and transport systems. Estimates for retro-fitting Britain's ageing power stations are as high as £1bn each.
Conclusions Critics argue that CCS cannot reduce global CO2 emissions in time to avoid a 2oC increase in global temperature. Over the next 20 years, only 7Gt CO2 will be sequestrated. CCS has no place in a sustainable energy future because it relies on continued use of fossil fuels and has a negative interaction with the elements of a renewable low energy system.
Conclusions CCS technologies are being developed at Hatfield colliery near Doncaster where plans for a 900MW clean coal power station, run on hydrogen extracted from coal are currently being allied to CCS technologies to capture 90% of the CO2 emissions and pipe them to the North Sea for geological storage. Legislative and financial support for clean coal allied with CCS would ensure that the UK has an environmentally friendly, secure and indigenous supply of energy for decades to come. In addition, jobs created within a nascent clean coal industry would give a lifeline to mining communities that have seen a quarter of a century of economic and social decline.
Conclusions Will ‘peak coal’ ever be a concern? “I don't think we'll ever experience peak coal... The Dakotas, Mississippi, Alabama, Louisiana, Texas all have large, large amounts of lignite. Or in China[‘s] Xinjiang province... there's a trillion tonnes of resources [that] will be the new Middle East. Anyone who has the notion that we're going to move away from fossil fuels just isn't paying attention.” Fred Palmer, Peabody Energy
more information http://ccs-info.org/index.html http://www.vattenfall.com/en/ccs/index.htm http://www.zeroemissionsplatform.eu/