In a key milestone on the road to harnessing fusion power, Lawrence Livermore laboratory announced this week that it had extracted energy from an object the size of a lemon pip at the rate of 10 quadrillion watts (joules per second), albeit for only 100 trillionths of a second. That’s roughly 500 times faster than the entire human population consumes energy.
The experiment is a reminder that the energy density achieved when atoms merge is vastly greater than anything in a lump of coal, let alone a puff of wind. It is also far bigger than can be achieved by nuclear fission and much safer too: no risk of meltdown and with much less high-level radioactive waste.
The problem, of course, is that reliable fusion power stations were 50 years away in 1950, and were still 50 years away in 2000, so milestones on the road to fusion are greeted with sceptical yawns. But almost everybody in the industry now thinks that jibe is out of date: the stopwatch has started, as one insider put it to me. We are probably less than 15 years away from seeing a fusion power station begin to contribute to the grid.
Two bits of evidence support that conclusion. First, the British Government will soon announce that it has chosen a site for a prototype government-developed power station, known as Step, the spherical tokamak for energy production, which will be operating around 2040. Secondly, there has been a gold rush of nearly $2 billion of private money into commercial fusion companies: several in the United States, one in Canada and two in Britain.
In terms of expertise and infrastructure, the UK is near the front of the peloton in this technology. The recent progress is mainly because of technical breakthroughs. In one design, called magnetic confinement, better superconductors have led to stronger magnets needing less cooling which allows more compact, spherical designs that can stabilise the “plasma” for longer spells of time. In another, inertial confinement, lasers developed for the star-wars missile defence programme have brought ignition temperatures within reach.
Before you get cynical, indulge in a bit of hope. If this were to work, then a device the size of a shipping container could power a small city, running on tiny quantities of fuel: some deuterium extracted from seawater and some tritium continuously “bred” inside the thing itself from a little lithium. The output is helium-4, an inert, non-radioactive gas. The environmental footprint would be negligible: no carbon dioxide emissions, no waste, no pollution, very few materials and a pocket-handkerchief of land. We could retire the rest of the energy industry altogether – oil rigs, coal mines, wind turbines, solar farms, hydro dams and all – and set about raising everybody’s standard of living indefinitely, while telling Greta Thunberg to cheer up.
Yet even if all goes to plan it will not be till after 2050 that fusion starts to make a big difference. So those countries that rushed to net zero by 2050, like us, using immensely expensive, resource-hungry, land-hungry renewable energy, will look foolish if fusion comes along just after. A bit like – only on a far grander scale – the way we made a huge mistake by mandating the switch to ineffective, unreliable, unsafe compact fluorescent light bulbs instead of waiting for more efficient and better LEDs.
The point is not that fusion will certainly come to our rescue, but that there’s probably a 50-50 chance that it will, and governments need to clear the runway to make sure it at least gets a chance to take off. That means learning the lessons from how we killed nuclear fission by driving up its cost. Far from getting cheaper like computers did, fission reactors grew steadily more expensive. This was because we never gave them the chance to profit from experience, to learn by doing. Designs were approved ever more slowly and expensively, gold-plated in a doomed attempt to reassure the public, never improved by tinkering during construction, rarely mass produced to bring down the unit cost, and then built by cost-plus contractors ripping off naive governments.
We have made a start in this country. The Regulatory Horizons Council, on which I sit, has recently produced a report arguing that it makes much more sense to regulate a fusion plant as if it were a chemical plant – through the Health and Safety Executive and the Environment Agency – than through the Office for Nuclear Regulation. That is because the risks do not include meltdowns, or high-level (or long-lasting) radioactivity, but are much more like those of a conventional industrial facility.
Investing in a technical fix like fusion looks more likely to deliver net zero – albeit not before 2050 – than frantically trying to soup up a 13th-century technology to extract energy from an ultra-low-density source: the wind.
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