Bill Gates appears via video conference – Microsoft Teams, not Zoom, obviously – from his office in Seattle, a large space with floor-to-ceiling windows overlooking Lake Washington. It’s a gloomy day outside and Gates is, somewhat eccentrically, positioned a long way from the camera, behind a large, kidney-shaped desk; his communications manager sits off to one side. “As a way to start,” says Gates’ aide, “would it be helpful for Bill to make a couple of comments about why he wrote his new book?”  

Unlike the Elon Musks or Larry Ellisons of this world, however, Gates is perceived to be sensible, uxorious, modest, vowing not to ruin his children with boundless inheritance or to waste energy trying to send things to Mars. Gates’ new book, How To Avoid A Climate Disaster, grew out of two things: his interest in the sciences and what struck him as an irresistible challenge – the fiendishly difficult problem of how to further global development while reducing emissions.  

There’s another, greater obstacle to reaching zero emissions, which is the political challenge – part of which involves climate activists limiting their exposure to accusations of hypocrisy. Gates loves private jets; he calls them his “guilty pleasure”.  

The depressing part of the book is its account of the challenge ahead, which Gates presents as extremely urgent – He points to a headline figure: 51bn. This is the amount of greenhouses gas, in tons, emitted globally each year, which we have to get down to net zero by 2050. The first step towards this is understanding what we’re dealing with.