News
Study finds potential for larger-than-expected impact of reducing consumption
Published 27 July 2010 in Climate Change
A recent study from the Grantham Institute for Climate Change at Imperial College London and published in the journal ‘Energy Policy’ shows that switching off lights, turning the television off at the mains and using cooler washing cycles could have a much bigger impact on reducing carbon dioxide emissions from power stations than previously thought. The study shows that the figure used by government advisors to estimate the amount of carbon dioxide saved by reducing people’s electricity consumption is up to 60 percent too low.
Dr Adam Hawkes, the author of the study, says the government should keep track of changing carbon emission rates from power stations to ensure that policy decisions for reducing emissions are based on robust scientific evidence. Power stations that supply electricity vary in their carbon dioxide emission rates, depending on the fuel they use: those that burn fossil fuels (coal, gas and oil) have higher emissions than those driven by nuclear power and wind. In general only the fossil fuel power stations are able to respond instantly to changes in electricity demand. The new study suggests that, as a result, excluding power stations with low carbon emission rates, such as wind and nuclear power stations, and focussing on those that deal with fluctuating demand would give a more accurate emission figure.
Scientists advising government on for the best ways to reduce electricity demand currently use an estimated figure for emission rates. The new study shows that, at 0.43 kilograms of carbon dioxide per kilowatt hour of electricity consumed, this figure is 60 percent lower than the actual rates observed between 2002 and 2009 (0.69 kilograms of carbon dioxide per kilowatt hour), meaning that policy studies are underestimating the impact of people reducing their electricity use.
"One way governments are trying to mitigate the effects of climate change is to encourage people to reduce their energy consumption and change the types of technologies they use in their homes,” states Hawkes. “However, the UK government currently informs its policy decisions based on an estimate that, according to my research, is lower than it should be.”
Professor Sir Brian Hoskins, Director of Imperial's Grantham Institute for Climate Change, said: "This is a very important study that could help policy makers make more informed decisions to reduce our carbon emissions. The government needs a good understanding of the figures it uses to support policy analysis, because this has a big impact on which technologies we employ to reduce our energy use. With a more accurate picture of what is going on, we will be much better equipped to tackle our carbon dioxide emissions."
The full report:
Estimating Marginal CO2 Emissions Rates for National Electricity Systems. Energy Policy, published online 22 June 2010.