Clean energy from nuclear fusion is our planet’s best hope
Jaspreet BindraMy last article in this publication (https://bit.ly/331TnYj )presented a dystopian view of how most exciting digital technologies, like Artificial Intelligence, Blockchain, the Cloud and even the humble computer are rapidly depleting our natural resources, contributing heavily to global warming and climate change. The article disappointed my largely technophile readers, given the prevailing narrative that these technologies are ‘clean’ and supposed to save the planet, not destroy it. The question that got thrown back at me: Is there a technology or a set of technologies that can actually save the world? I will stick my neck out and say that there is one: nuclear fusion.
Stephen Hawkings perhaps felt the same when he said, “I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy, without pollution or global warming.” Nuclear fusion or nuclear fusion is not a new concept, scientists have known about it since Einstein’s times, and it is the phenomena that powers our Sun. As Anjana Ahuja writes in the Financial Times (on.ft.com/3Ef6Auo): “The fireball at the heart of our solar system is powered by nuclear fusion. The crushing pressures in the sun’s core squeeze hydrogen nuclei together so powerfully that they overcome their natural repulsion and fuse. These nuclear clinches generate larger particles with masses that are not quite the sum of their parts. The missing mass becomes energy, a fiery embodiment of Einstein’s equation E=mc2. The equation shows that in terms of energy production, a tiny bit of mass goes a long way thanks to the colossal multiplier of c, the speed of light (300,000km per second), squared.” Fusion is not the same as fission, where the nucleus of an atom splits into two or more smaller nuclei, releasing the vast amounts of energy holding them together, thus powering nuclear reactors and thermonuclear bombs. Fusion, which uses widely available chemicals like deuterium and tritium, can theoretically extract an energy equivalent of a million gallons of oil, from one glass of these! This can produce 9 million KWH of electricity, enough to power your house for some 800 years.
No wonder physicists have been attempting to play God and trying a fusion reaction for many decades. The first successful experiment was in the 1950s, when Soviet physicists built the first fusion prototype using a method called magnetic confinement fusion. This apparatus, called the Tokamak (a Russian short form for Toroidal Chamber with Magnetic Coils), has become the model for most further experiments. This trapped deuterium and tritium plasma in place using super-powerful magnets and fused their nuclei by heating them to temperatures hotter than the sun. The experiment created helium and vast amounts of energy, the first successful fusion in a lab. The problem is that the energy used to make this happen exceeded the energy released, defeating the purpose and making the process ‘hot’ and not ‘cold’ fusion. This disappointing result has repeated itself since; no one has been able to generate more energy than the system consumes, and this planet-saving technology remains a gleam in every nuclear physicist’s eye.
However, a few recent experiments by governments and private entities have given us cause for hope. A recent FT article (https://on.ft.com/3rtRrlh ) by Wilson and Bott describes excitement over nuclear-fusion experiments among startups. A Chinese Tokamak sustained a fusion reaction at 120 million degree Celsius for a record 101 seconds. The National Ignition Facility in the US created huge excitement by using 192 lasers to generate a fusion reaction that came the closest ever so far to achieve net energy, where the energy produced was about 70% of what was used, and much greater than earlier attempts. The next aim is to reach “break even”, with as much energy produced as used up.
Nuclear fusion startups are burgeoning, the Fusion Industry Association estimates 35 of them, and growing. Bill Gates, Peter Theil and Jeff Bezos are investing in them; about $5 billion of venture capital has been deployed. A recent startup, Commonwealth Fusion raised $1.8 billion, while Sam Altman put $375 million into another called Helion. Not all of them will succeed, but even if one does, it will gives us unlimited clean fuel to power our planet forever, much like the sun has been doing.
“Nobody has a better plan to deal with the climate crisis,” said David Kingham, a fusion entrepreneur. I agree. This is the one technology that could save our planet from the apoplectic future that we ourselves have wrought.