The Report from Working Groups I (on the science of climate change) and II (on the impacts of climate change on human society) were – inevitably – deeply depressing. The science is what it is, and won’t go away. And the grim analysis of what this means for humankind (unless we change our ways dramatically and urgently) flows with an unavoidably ruthless logic from that science.

So the Report from Working Group III came as a massive relief! If governments get moving now, and stick with the challenge of radical decarbonisation over the next twenty years, then we can still crack it. By which, I mean have a reasonable prospect of avoiding runaway climate change. Or even irreversible climate change.

Its analysis of the global energy system is particularly refreshing. It basically confirms that a combination of measures to promote massive improvements in energy efficiency, a tripling of levels of investment into renewable energy, together with the accelerated deployment of storage technologies and “smart grids”, will do it. It’s not too late.

(This is, of course, the “big picture story” that I set out to tell in The World We Made. So I obviously found myself letting out a great big (metaphorical) sigh of relief to have the “doability” of that story so authoritatively confirmed!)

Renewable energy already provides 21% of world electricity demand, and the IPCC calculates that the combined potential of all renewables over the next few decades could meet total primary energy demand (i.e. electricity plus heat plus transportation) nearly three times over. Just let that one sink in a moment. Nearly three times over!

Of all those renewable energy technologies, solar energy has the biggest potential – as many have been arguing for a long time. As the Solar Trade Association commented last week:

“The IPCC calculates that solar energy has the largest technical potential – the “largest by a large magnitude” – exceeding world energy demand on its own. Solar power is also highlighted as being exceptionally rich in the employment opportunities, with eighteen and seven times more jobs per unit of power generated than nuclear and wind energy respectively.”

So this confirms the benefits of having a clear solar strategy for the UK, with a target of 1 million solar roofs by 2015. Important to praise the Government for that, but if you ask me, it’s still doing solar half-cock. It’s still ignoring the huge potential for large solar installations on roofs, refusing to amend the current Feed-in Tariffs to liberate that potential market. As usual, it’s running scared of the Big 6 on this one. They are all petrified they might see a similar reduction in their total available market as has already happened in Germany.

In The World We Made, the front cover of The Economist in 2016 tells a simple story: “Solar Sweeps the Field”. Just two more years! Just wait and see!