In the weekend’s Financial Times, Bill Gates outlines his green manifesto for corporate action. He lists four categories for the urgent attention of CEOs: investment, procurement, R&D and political dialogue. Companies can invest in green capital; buy their supplies from green providers; support green research; and express green opinions to their political representatives. He also suggests actions for policy makers, including proper carbon pricing.

Hard to disagree with any of that. But the elephant in the room, or perhaps I mean in his room, is our level of consumption.

Although he avoids mentioning it in the article, Gates is on record as saying that reducing consumption is not going to solve global warming. Which is not a surprise. We all justify our own choices; and someone who owns private jets is not going to take kindly to the suggestion that it would be helpful to get rid of them.

Instead, he offers up the idea that aviation emissions can be sorted out by switching to biofuels. Apparently he spends about $400 per tonne of emissions in purchasing biofuels to offset his plane trips; and he maintains that if enough wealthy individuals were to copy his example, prices would fall to a level that is more practical for normal impecunious travellers.

Up until this point, his article is refreshingly realistic. He points out, for instance, that trees have limited impact – that to offset American greenhouse gas emissions from tree planting, it would be necessary to cover over half of the Earth’s landmass with forests dedicated to the purpose. And that Americans make up just 4% of the global population, so even if such geo-engineering were internationally agreed upon, how could trees offset the other 96% of humanity?

It is understandable, if a little ironic, that this global realism fails him when he switches to the related topic of biofuels for aviation. But just as the Earth simply isn’t big enough for tree planting to offset the Western lifestyle, so biofuels are unlikely to meet the sector’s current energy demand, let alone a demand level that is inflated by widespread use of private jets.

A practical manifesto

A more realistic manifesto would tackle our levels of consumption. Reducing our usage of energy and materials is something most of us can do straightaway, without waiting for new technologies, economic frameworks or government policies. (The natural world is not waiting for them either.) If a large proportion of us consumers were, for the sake of argument, to knock a third off our current demand for fossil fuels, the impact would be greater than from any single technology or any government action, national or international.

People ask: what about jobs? what about tax-funded services like the British NHS? If we don’t ‘consume’, i.e. spend money, then the economy and social services will collapse. Or so goes the argument. The simple truth is that we could live in a world where we are materially poorer, in which jobs are greener and less well paid but not necessarily fewer in number, and in which welfare expenditure is protected, even if that means it uses up a higher proportion of our income than it does today.

We might even be happier. But because we are reluctant to give up what we have – even if it provides little enjoyment – we tell ourselves it is unreasonable, even economically naive, to ask people to consume less; that Gates is right, and salvation lies in technology.

Perhaps a reduction in the usage of energy and resources will result from meaningful (i.e. many times higher) carbon prices, which indeed he advocates. Timing is against us though; we cannot really afford to wait for politicians to agree on the economic mechanisms required to deliver these eye-watering prices or taxes.

Mathematicians and logicians like to distinguish between conditions that are necessary and conditions that are sufficient. In this language, Bill Gates might be correct that reducing our consumption levels will not be sufficient to halt global warming – and hence his manifesto; but, short of technological miracles, it is a condition for the survival of future generations that is almost certain to be necessary.