Power Generation

A new study indicates that switching off lights and electrical appliances when not in use, as well as choosing more efficient models, has more impact on reducing CO₂ emissions than previously thought.

Adam Hawkes of the Grantham Institute for Climate Change at Imperial College London looked at the estimated figure for emission rates that the UK Government uses to calculate the impact of energy efficiency measures. His analysis shows that this estimated figure could be up to 60% too low.

The argument centres on how the estimated figure is determined. Currently, the Government uses an average across all forms of generation to come up with a value of 0.43 kilograms of CO₂ per kilowatt hour of electricity consumed.

This figure includes low-carbon energy sources such as wind and nuclear. These energy sources, however, are not able to respond to instantaneous fluctuations in electricity demand – which is where fossil fuel power plants come in.

Hawkes calculates that the actual rate observed between 2002 and 2009 is 0.69 kilograms of CO₂ per kilowatt hour.

“This means any reduction we make in our electricity use – for example, if everyone switched off lights that they weren't using, or turned off electric heating earlier in the year – could have a bigger impact on the amount of carbon dioxide emitted by power stations than previously thought,” he says.

The findings could be important for policy makers to help make more informed decisions on reducing carbon emissions. Hawkes adds that it emphasizes the importance of doing everything we can to reduce electricity usage.

For further information:
A.D. Hawkes. Estimating marginal CO₂ emissions rates for national electricity systems. Energy Policy (2010), doi:10.1016/j.enpol.2010.05.053