Sir

We find that the European Union's proposed directive on carbon-capture 'readiness', as reported in your News story 'Europe to capture carbon', is unacceptable (Nature 451, 232; 2008). It clears the way for a new generation of coal-fired power stations to be built in Europe without any abatement of emissions when they start operating, and without any certainty about when, or if, such technology will be available and affordable.

Already, proposals for new coal plants that will emit tens of millions of tonnes of carbon dioxide are working their way through the planning systems of several European countries. In Britain, for instance, plans for the energy company E.ON's proposed coal power station at Kingsnorth in the Medway estuary, Kent, are with the business secretary, John Hutton, and there's no certainty that he will call a public inquiry to examine the national and international implications.

If allowed, Kingsnorth would start generating in 2012, even before the UK carbon-capture demonstration projects are up and running. With every year that passes without such technology being retrofitted, it would emit more than seven million tonnes of carbon dioxide — ten times more than the entire annual emissions of Rwanda.

If Europe's member states are serious about climate change and meeting the targets they have set themselves for reducing harmful emissions, they will impose strict standards of greenhouse-gas efficiency on all new power stations. New coal-fired power plants of the kind proposed at Kingsnorth should be reconsidered only if carbon capture and sequestration are proved safe, effective and commercially available for fitting from the moment they begin to burn fuel.