Global warming is a problem that needs solving. Polly Toynbee's fellow Guardian columnist George Monbiot is infuriatingly demanding when it comes to carbon dioxide emissions.
"A 90% emissions cut by 2030" is one of Monbiot's stated goals. Although this is technically feasible, it almost certainly won't happen.
The problem is energy. If you list, as Richard E. Smalley does in his Terawatt Challenge, the biggest issues facing humanity over the next 100 years you would probably get something like this:
6. Terrorism and war
A moment's consideration reveals that energy is fundamental to all of the problems after energy, with the possible exception of terrorism, war, and democracy - but there is no denying that the politics of energy have an enormous effect on war and terrorism. With enough energy you can accomplish anything.
As of this moment there is a vast chunk of humanity (>4 billion) with access to considerably less energy than I do. This is unfair, of course, and in order to promote increased living standards we need to find energy for all the people who don't have enough.
Monbiot's argument in Heat is that we in the UK are currently using "too much" energy. This is inaccurate. We are using precisely the amount of energy we choose to consume. We are however emitting too much carbon dioxide.
In order to stop the twin catastrophes of global warming and global poverty we need more energy and less CO2 emissions. This will be difficult and will require many of the solutions already suggested: increased efficiency, nuclear power, sequestration, and lifestyle alterations.