I had the chance to speak to the University of Edinburgh's Professor of Power Plant Engineering and Carbon Capture, Jon Gibbins, last week, for a piece in next week's magazine. During the course of our interview, he focused heavily on an argument for using carbon capture and storage (CCS) technology which I hadn't heard before.

He said:

We've never really been short of fossil fuels. We thought we were, but really it's obvious, and maybe this gas business makes it painfully obvious that we're not short of fossil fuels. We are short of space in the atmosphere. And nobody knows what the climate response would be. There's a wide range of predictions, but there's enough fossil fuel to take you anywhere within that range of predictions that you want to go. And you really don't want to be sitting there having that experiment.

So as I say, we've got two choices, I think. We've got the choice of saying that renewables are so wonderful and cheap – or nuclear or anything else, or fusion – will be so cheap that we don't use the fossil fuels. They're just too easy to use. So we either sit there and keep on putting fossil carbon in the atmosphere, and see what happens, and then probably what happens is you realise it's not a good idea and you have to do things in a panic.

Now, maybe a few people would be doomed – or maybe more than a few – in that situation. Or, we say look, how much money are we spending on renewables? Even in our straitened times, quite a lot. How much would it cost to spend an equivalent amount of money on CCS? Well it wouldn't cost us a thing, actually. Because you're just shifting money from one low-carbon source to another. That's all. It's not energy costing money, it's just not spending all of it in one direction.

In other words, we ought to focus on CCS at least as much as – if not more than – renewables, not because they are better per se, but because they are better at constraining future action. Only if we burn fossil fuels with CCS can we be sure that the carbon they contain won't enter the atmosphere some other way.

If we build enough renewable energy capacity to supply our entire system, there are still fossil fuels ready to burn. The people who built the renewable capacity may not want to burn them – but what about the next government? Or the next generation?

The history of humanity is a history of ever increasing energy demand. As a result, we ought to assume that any un-used energy source won't stay that way for long. If we do assume that, then maybe the best thing to do isn't try to completely end our usage of fossil fuels, but to ensure that if we use fossil fuels, we only ever use them in a safe way (that is, with CCS technology).

There are two potential advantages to this: firstly, it gives us more time to prepare an energy system totally unreliant on fossil fuels, and secondly, it means that when we do switch to a renewable economy, there's no chance of freaking out and switching back.

The full interview with Professor Gibbins will be in the 4 November edition of the New Statesman.