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Climate change and energy

Why the dream of fusion power isn’t going away

Fusion could supply round-the-clock power with no carbon emissions, if it can overcome massive technical challenges. We shouldn’t give up on it.

September 28, 2023
an atomic model in a slingshot aimed past the moon to hit another atomic model on the far side
Stephanie Arnett/MITTR | Envato

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There’s a joke about fusion power that always comes up when people start talking about the technology. It goes like this: Fusion is the energy of the future … and it always will be.

Fusion reactors could someday deliver cheap, abundant power with no carbon emissions using abundant fuel. But the promise of “someday” has been around for a long time without payoff. I’m fascinated by the way fusion has generated so much excitement and also so much skepticism. It’s the ultimate long shot in energy technology. 

At our ClimateTech event next week, I’ll be chatting with Daniel Brunner, co-founder and chief technology officer of Commonwealth Fusion Systems. So for the newsletter this week, let’s consider the role of long-shot technologies like fusion that could change everything for climate change. 

Promise and perils

Fusion is sometimes referred to as a “moonshot” technology: a lofty goal that would be transformative, but is technically really tough to pull off. 

The original moonshot that popularized the term was literally about the moon—US President John F. Kennedy announced in 1962 a goal of getting to the moon by the end of the decade. (It says something about how long we’ve been waiting for fusion that research on the technology actually predates this first moonshot.)

A fusion reactor slams atoms into each other, causing them to fuse and release vast amounts of energy. The process uses cheap, abundant fuel. That could mean around-the-clock power that doesn’t generate any carbon emissions: a dream combination for addressing climate change. 

But getting this fusion to happen in a controlled way requires multiple feats of science and engineering. Temperatures inside the reactor need to top 100 million °C (180 million °F), and companies have to rely on lasers, super-powerful magnets, or equally high-tech contraptions to hold the fuel in place.

Because of all that complicated engineering, some modelers predict that fusion might not actually turn out to be all that cheap, falling somewhere around or just above the cost of renewables. (Read more in this story from Wired earlier this year.) I see the argument here, but also, forecasters have underestimated the potential of solar panels for over a decade, so I’m not sure I’m ready yet to make a solid argument one way or another about fusion’s eventual cost. 

Regardless, this is a potentially transformative technology. The question is when fusion will be ready for prime time, and if that will be soon enough to do anything about climate change. 

Path and progress

When it comes to future prospects for fusion, I’m watching with interest, excitement, and a healthy serving of skepticism. It’s important to go after long-shot technologies, even if the odds are stacked against any single company or approach working out. 

This feels like an especially positive moment for fusion, because as you might remember, the technology had a huge scientific moment a little less than a year ago. For the first time, scientists at Lawrence Livermore National Laboratory were able to generate more energy from a fusion reaction than what was delivered into the fuel.

With those reactions, fusion reached what’s sometimes called scientific breakeven—a huge milestone by any definition. But, of course, there were caveats. 

The lasers in this reactor are some of the most powerful in the world, but they’re also pretty inefficient. In the end, more power was pulled from the grid than what the fusion reactions produced. And most experts agree that this version of fusion isn’t super practical for power plants, at least in the near term. 

While this was a milestone, it was more symbolic than practical. And it’s notable that in the meantime, the world’s largest and most famous fusion project is languishing—the massive international collaboration ITER (International Thermonuclear Experimental Reactor) has been plagued with delays and exploding costs. 

But amid slow progress from national and international research efforts, the private sector has shown a lot of interest in fusion power. Cumulative investment reached $6.2 billion earlier this year. Investors are still putting money into the technology, with many citing the need for innovative climate technologies and recent progress in the private sector.

While no private fusion company has achieved net energy (or at least, hasn’t announced it), there have been some milestones to mark. Commonwealth Fusion Systems has broken records for magnetic field strength with its new superconductor materials, a technology that could be the key to making fusion work economically at scale. Other startups, like TAE Technologies, have celebrated temperatures of 75 million °C, or even hotter, another key stepping stone to reaching viable fusion reactors. 

I think it’s exciting to see more startups jumping in on fusion energy. There’s a sense of urgency from these companies, because they need to make progress and continue raising money or risk going out of business. 

Commonwealth Fusion Systems plans to flip on its reactor and generate net energy around 2025, and have a plant running in the early 2030s. Helion Energy (which at one point planned to be operational by 2020) is now planning for its plant to come online as early as 2028. The company already has a power purchase agreement in place with Microsoft. 

But experts are skeptical, as my colleague James Temple outlined in his story about Helion’s announced timeline earlier this year.

Potential and prospects

I wouldn’t necessarily bet the planet on fusion, but I don’t think that’s what’s happening.

We have technologies on the table to address climate change right now. For the next decade or so, deploying wind and solar power, electric vehicles, and other available tech will be what helps us reach our emissions goals. 

There’s often a concern that funding fusion will pull money away from the technologies that have a higher chance of having an impact in the near term. But investments aren’t necessarily a zero-sum game. The pot also feels bigger now, with the Inflation Reduction Act in the US putting a half-trillion dollars toward climate technology over the next decade.

It’s possible to acknowledge that existing tech is going to have the biggest impact in the near term while also believing that new technologies, like next-generation batteries, hydrogen-powered heavy industry, and even fusion, could potentially play a massive role in a future version of our world. Having more options on the table come 2030 or even 2040 definitely couldn’t hurt—and while I’m not sure yet which ones those might be, I’m keeping my eyes out. 

If you’re interested to hear more about high-risk, high-reward technologies, be sure to join us at ClimateTech next week—there’s still time to register! In our final session, I’ll be speaking with experts on fusion, large-scale carbon removal, and electric aviation, technologies that could really change everything. Hope to see you there!

Related Reading

Here’s what the first fusion reactor reaching breakeven really means for clean energy.

Commonwealth Fusion Systems thinks its reactor could be the first commercial success for fusion power. My colleague James Temple wrote about the company’s progress when it mostly still looked like a hole in the ground.

Helion claims its first commercial reactor is just five years from startup, but experts have doubts this moonshot will land so soon.

MIT Technology Review has been bringing you the news on fusion for over half a century. Check out a few excerpts on fusion from the archives.

Another thing

The European Commission could be putting the brakes on China’s electric vehicle exports. China’s newfound status as a major auto exporter has raised red flags in Europe, where about 6% of the continent is employed in the domestic auto industry. 

Read more about the fascinating geopolitics of EVs in the latest story from my colleague Zeyi Yang. And if you want to hear more about how China came to dominate the world of EVs, check out his story from February.

Keeping up with climate  

Lego has axed plans to make its iconic bricks from recycled bottles. Using the material required extra steps and more energy, so it didn’t help cut carbon emissions, according to the company. (BBC)

Firefighters have a new tool in the fight against wildfires: AI. The technology can help spot blazes sooner, which could be crucial as climate change makes fires more frequent in some parts of the world. (Bloomberg)

I loved this deep dive about sweat and how climate change is pushing the limits of the human body. (Grist

Long duration energy-storage projects just got a big boost, to the tune of $325 million from the US Department of Energy. This type of technology could be crucial to support renewables on the grid. (Canary Media)

→ Among the winners: Eos and its zinc-based batteries. The company recently received a loan from the DOE for its Pennsylvania factory. (MIT Technology Review)

→ Italian startup Energy Dome also received funding. Learn more about how the company is using compressed carbon dioxide for energy storage in this 2022 story. (MIT Technology Review)

Remember that multibillion-dollar factory Ford was building to produce low-cost EV batteries? It’s on pause. The company cited concerns about being able to competitively operate the plant. Auto workers currently on strike say the move is a veiled threat to cut jobs. (Yahoo)

→ I’ve been following the factory since the company announced plans in February. It could be a big deal for lithium iron phosphate batteries, a low-cost technology. (MIT Technology Review)

There are a lot of potential problems with carbon offsets—businesses and individuals paying for others to reduce emissions on their behalf. This new wide-ranging project from Carbon Brief attempted to round up lots of evidence to this effect. (Carbon Brief

Efforts to cut down on emissions from shipping have had an unintended consequence: heating up the planet. The effect is especially clear in the high-traffic Atlantic Ocean. (Science)

Usually we think of hydrogen as a fuel we need to make, using either fossil fuels or renewable electricity. But there could be more hydrogen resources underground than previously thought. (New Scientist)

Deep Dive

Climate change and energy

The problem with plug-in hybrids? Their drivers.

Plug-in hybrids are often sold as a transition to EVs, but new data from Europe shows we’re still underestimating the emissions they produce.

These artificial snowdrifts protect seal pups from climate change

The human-built habitats shield the pups from predators and the freezing cold, but they’re threatened by global temperature rise.

How thermal batteries are heating up energy storage

The systems, which can store clean energy as heat, were chosen by readers as the 11th Breakthrough Technology of 2024.

The hard lessons of Harvard’s failed geoengineering experiment

Some observers argue the end of SCoPEx should mark the end of such proposals. Others say any future experiments should proceed in markedly different ways.

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