EDF Energy has taken a step backwards in its push towards going green, according to its latest sustainability report.
Its total carbon footprint rose 40% from 15 million tonnes in 2011 to 21 million tonnes in 2012. Some of that was accounted for by increased generation, which rose from 72TWh to 84TWh.
The amount of carbon dioxide released for each unit of power rose from around 208 tonnes per gigawatt hour (tonnes/GWh) to 252 tonnes/GWh, a rise of more than 20%.
It marks a turnaround for the company, which had reduced emissions the previous year. The increase was expected but EDF still fell short of its target of 250 tonnes/GWh in 2012.
The report said the worsening emissions figures are largely down to the increased operation of their coal-fired stations.
Nitrous Oxide emissions rose from 0.4 tonnes/GWh in 2011 to 0.46 tonnes/GWh in 2012, an increase of around 15%. The equivalent sulphur emissions grew by roughly 1%.
The company has pledged to reduce carbon dioxide emissions to 60% compared to 2006 levels. It claims it will still be able to meet that target by building new nuclear reactors, extending the lives of existing ones, building cleaner gas powered plants as well as using renewable sources of energy.