It's not surprising that neither Labour nor the Tories wanted to run the Guardian's National Carbon Calculator. Had they done so, they would have had to acknowledge that the figures on which they base their climate change policies are a work of science fiction. The government claims that our total emissions amount to 627 million tonnes of CO2 equivalent (MtCO2e). The Tories have never disputed this figure. It's convenient for both sides to accept this falsehood, and to pretend that the challenge is far smaller than it is.
Fully story at Guardian website.