Nuclear fusion for the grid is coming much sooner than you think
Britain is on the brink of striking gold in the race for limitless energy
Commercial nuclear fusion has gone from science fiction to science fact in less than a decade. Even well-informed members of the West’s political class are mostly unaware of the quantum leap in superconductors, lasers, and advanced materials suddenly changing the economics of fusion power.
Britain’s First Light Fusion announced last week that it had broken the world record for pressure at the Sandia National Laboratories in the US, pushing the boundary to 1.85 terapascal, five times the pressure at the core of the Earth.
Days earlier, a clutch of peer-reviewed papers confirmed that Commonwealth Fusion Systems near Boston had broken the world record for a large-scale magnet with a field strength of 20 tesla using the latest high-temperature superconducting technology. This exceeds the threshold necessary for producing net energy, or a “Q factor”, above 1.0.
“Overnight, it basically changed the cost per watt of a fusion reactor by a factor of almost 40,” said Professor Dennis Whyte, plasma doyen at the Massachusetts Institute of Technology (MIT). The March edition of the IEEE Transactions on Applied Superconductivity published six papers ratifying different aspects of the technology.
The magnets are used to fuse hydrogen isotopes by squeezing super hot plasma inside a tokamak device. The temperature must be ten times hotter than the surface of the sun in order to replicate solar fusion because the Earth’s magnetic field is that much weaker.
The “old” low-temperature magnets are made of niobium alloys operating near absolute zero at -270C. The new magnets lift the temperature from 4 kelvins to 20 kelvins using rare earth barium copper oxide (ReBCO) with a radical new design. They combine superconductivity with extreme magnetic power. This leverages a “multiple order-of-magnitude increase” in fusion capability.
Commonwealth’s chief executive, Bob Mumgaard, told me the game-changing technology scarcely existed 10 years ago, and was still in its infancy five years ago. “The breakthrough is in superconductors. Much stronger magnets mean that we can build a plant that is 40 times smaller,” he said.
It is time to drop the old joke that fusion is 30 years away, and always will be. A poll at the International Atomic Energy Agency’s forum in London found that 65pc of insiders think fusion will generate electricity for the grid at viable cost by 2035, and 90pc by 2040.
The Washington-based Fusion Industry Association says four of its members think they can do it by 2030. If the industry is anywhere close to being right, we need to rethink all our energy assumptions. Britain’s planned gas plants are rendered obsolescent almost before they are built.
In late December, China launched its own fusion consortium, combining its top universities and state industries in an Apollo-style national endeavour. “Controlled nuclear fusion is the only direction for future energy,” said the State Council. This is the new front in the technology arms race.
The world’s long-running $20bn ITER research project, a consortium of the US, Japan, Europe, China, and Russia, looks ever more like a beached whale in this contest. It has collected valuable science over the decades but has been dogged by geopolitics and delays, and has never produced more energy than it put in, unlike the Lawrence Livermore lab in the US using the rival technology of inertial fusion.
The baton has passed to tech tycoons in a hurry. Commonwealth Fusion, a spin-off from MIT’s Plasma Science and Fusion Centre, is backed by Bill Gates, Jeff Bezos, and Sir Richard Branson. It aims to produce its first plasma next year and reach a steady Q factor of 10 by the late 2020s, the energy target for commercial take-off.
Dr Mumgaard said Commonwealth is eyeing costs of $60-80 MWh with scale, undercutting the 24/7 cost of intermittent renewables paired gas peaker plants or with energy storage in most places. “It might be even lower. We don’t use uranium. There is no risk of melt-downs,” he said.
Regulators in the UK and the US plan to treat fusion plants like hospitals, since they use tiny amounts of deuterium-tritium. Radioactive release is nothing like a uranium fission reactor. This means they can be built almost anywhere and rolled out fast.
Britain is going gangbusters on all fronts, a legacy of ITER’s Joint European Torus project at Culham, but also a feat of leadership. “Of all the countries in the world, the UK is most aggressively pursuing fusion power,” said American scientists Matthew Moynihan and Alfred Bortz, co-authors of Fusion’s Promise.
They said the UK Atomic Energy Authority (UKAEA) under Sir Ian Chapman had done a masterful job in creating the Fusion Cluster and the £650m Fusion Futures Programme, accelerating the move from pure research to megawatts for the grid. “All this work has made the UK the technical leader in the race to fusion power,” they said.
Tokamak Energy near Oxford is a pioneer of the new ReBCO magnet technology, and may be sitting on priceless intellectual property.
The UKAEA is building its own tokamak on the site of an old coal-fired plant in Nottinghamshire, with a spherical design that has never been tried before but promises to slash costs.
England hosts three world-class fusion start-ups spanning the two key rival technologies.
First Light leads in inertial fusion. Two others are developing magnetic fusion: Tokamak Energy and Canada’s General Fusion, which is locating its demonstration plant at the Culham Campus, quite a coup for the Fusion Cluster. Any one of them has a chance of striking gold.
The allure of fusion is by now well understood. It generates four million times more energy than fossil power, without emitting CO2 or methane. It creates almost no long-term waste. Its main by-product is inert helium.
It uses almost no land, and little water, and can be made practically invisible. Unlike today’s fission, it produces industrial high-grade heat to help decarbonise glass, cement, steel, ammonia, hydrogen, etc. It runs continuously if you need it, or is dispatchable if you don’t.
The fuel is effectively limitless for thousands of years and can be obtained anywhere: deuterium from seawater, and tritium by breeding with small amounts of lithium. There is no risk of a runaway chain reaction. It does not use fissile materials and is useless for weapons.
Lev Artsimovich, the Polish-Russian father of the tokomak, was once asked when fusion would come of age. “When humanity really needs it,” he replied. So it is proving to be.
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