Nuclear fusion reactor could be here as soon as 2025

image of nuclear fusion reactor SPARC
A cutaway rendering of the proposed SPARC tokamak. (Image credit: CFS/MIT-PSFC - CAD Rendering by T. Henderson)

A viable nuclear fusion reactor — one that spits out more energy than it consumes — could be here as soon as 2025.

That's the takeaway of seven new studies, published Sept. 29 in the Journal of Plasma Physics.

If a fusion reactor reaches that milestone, it could pave the way for massive generation of clean energy. 

During fusion, atomic nuclei are forced together to form heavier atoms. When the mass of the resulting atoms is less than the mass of the atoms that went into their creation, the excess mass is converted to energy, liberating an extraordinary amount of light and heat. Fusion powers the sun and stars, as the mighty gravity at their hearts fuse hydrogen to create helium.

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But an enormous amount of energy is needed to force atoms to fuse together, which occurs at temperatures of at least 180 million degrees Fahrenheit (100 million degrees Celsius). However, such reactions can generate far more energy than they require. At the same time, fusion doesn't produce greenhouse gases such as carbon dioxide, which drive global warming, nor does it generate other pollutants. And the fuel for fusion — such as the element hydrogen — is plentiful enough on Earth to meet all of humanity's energy needs for millions of years.

"Virtually all of us got into this research because we're trying to solve a really serious global problem," said study author Martin Greenwald, a plasma physicist at MIT and one of the lead scientists developing  the new reactor. "We want to have an impact on society. We need a solution for global warming — otherwise, civilization is in trouble. This looks like it might help fix that."

Most experimental fusion reactors employ a donut-shaped Russian design called a tokamak. These designs use powerful magnetic fields to confine a cloud of plasma, or ionized gas, at extreme temperatures, high enough for atoms to fuse together. The new experimental device, called the SPARC (Soonest/Smallest Private-Funded Affordable Robust Compact) reactor, is being developed by scientists at MIT and a spinoff company, Commonwealth Fusion Systems.

If it succeeds, SPARC would be the first device to ever achieve a "burning plasma," in which the heat from all the fusion reactions keeps fusion going without the need to pump in extra energy. But no one has ever been able to harness the power of burning plasma in a controlled reaction here  on Earth, and more research is needed before SPARC can do so. The SPARC project, which launched in 2018, is scheduled to begin construction next June, with the reactor starting operations in 2025. This is far faster than the world's largest fusion power project, known as the International Thermonuclear Experimental Reactor (ITER), which was conceived in 1985 but not launched until 2007; and although construction began in 2013, the project is not expected to generate a fusion reaction until 2035.

One advantage that SPARC may have over ITER is that SPARC's magnets are designed to confine its plasma. SPARC will use so-called high-temperature superconducting magnets that only became commercially available in the past three to five years, long after ITER was first designed. These new magnets can produce far more powerful magnetic fields than ITER's — a maximum of 21 teslas, compared with ITER's maximum of 12 teslas. (In comparison, Earth's magnetic field ranges in strength from 30 millionths to 60 millionths of a tesla.)

These powerful magnets suggest the core of SPARC can be about three times smaller in diameter, and 60 to 70 times smaller in volume than the heart of ITER, which is slated to be 6 meters wide. "That dramatic reduction in size is accompanied by a reduction in weight and cost," Greenwald , told LiveScience. "That's really the game-changer."

In seven new studies, researchers outlined the calculations and supercomputer simulations underlying SPARC's design. SPARC is expected to generate at least twice as much as 10 times more energy as is pumped in, the studies found.

The heat from a fusion reactor would generate steam. This steam would then drive a turbine and electrical generator, the same way most electricity is produced nowadays. 

"Fusion power plants could be one-to-one replacements for fossil fuel plants, and you wouldn't have to restructure electrical grids for them," Greenwald said. In contrast, renewable energy sources such as solar and wind "are not accommodated well by the current design of electric grids."

The researchers ultimately hope SPARC-inspired fusion power plants would generate between 250 to 1,000 megawatts of electricity. "In the current power market of the United States, power plants typically generate between 100 to 500 megawatts," Greenwald said.

SPARC would only produce heat, not electricity. Once researchers have built and tested SPARC, they plan to construct the ARC (Affordable Robust Compact) reactor, which would generate electricity from that heat by 2035.

"That's very ambitious, but that's the target we're working toward," Greenwald said. "I think it's really plausible." 

Originally published on Live Science.

Charles Q. Choi
Live Science Contributor
Charles Q. Choi is a contributing writer for Live Science and Space.com. He covers all things human origins and astronomy as well as physics, animals and general science topics. Charles has a Master of Arts degree from the University of Missouri-Columbia, School of Journalism and a Bachelor of Arts degree from the University of South Florida. Charles has visited every continent on Earth, drinking rancid yak butter tea in Lhasa, snorkeling with sea lions in the Galapagos and even climbing an iceberg in Antarctica.
  • Wanda
    So, is this a good thing or a bad thing? Is there some reason we want humanity to stick around for millions of years?
    Reply
  • Crosseye
    Why not?
    Reply
  • jeffrey
    admin said:
    Nuclear fusion reactor could be here as soon as 2025 : Read more
    So by 2035? A 20 year prediction has been the norm. Maybe we have made progress as its15 years until.
    Reply
  • maxwellanderson842@gmail.
    Wanda said:
    So, is this a good thing or a bad thing? Is there some reason we want humanity to stick around for millions of years?
    I Have Fears Regarding This New Science Venture- I Know Only 4grms Of
    Fuel Will Only Be Used At Any One Time- I Can Only Hope The Mathematicians & Physicists - Have Exhausted All There Theories... Is It Possible We May Be Trying To Replicate The Sun & It's Awesome Powers- BE Careful We Do NOT Become The Next Sun In The Cosmos- I Believe More Intensive Research Is Needed Before The World Commits To This- { Let Us Not Forget } This Is A Science Project With One Thing We All Have In Common- The Need For Scientific Stardom & MONEY...
    Not Saying No. Just Allow The Greatest Minds Throughout The World To Give A Second Opinion- MONEY IS THE ROOT OF ALL EVIL. Am I The Only One Who Cares- The Devil Will Or Maybe Be Rubbing His Hands In Wait- let us Be Sensible Humans & Give This Project Just A Little More Scrutiny- Our Existence May Rely/Depend Upon It. I'm Not Being Alarmist- Chernobyl Was Described As SAFE-
    Reply
  • maxwellanderson842@gmail.
    Let Us All Look Before We Leap...
    maxwellanderson842@gmail. said:
    I Have Fears Regarding This New Science Venture- I Know Only 4grms Of
    Fuel Will Only Be Used At Any One Time- I Can Only Hope The Mathematicians & Physicists - Have Exhausted All There Theories... Is It Possible We May Be Trying To Replicate The Sun & It's Awesome Powers- BE Careful We Do NOT Become The Next Sun In The Cosmos- I Believe More Intensive Research Is Needed Before The World Commits To This- { Let Us Not Forget } This Is A Science Project With One Thing We All Have In Common- The Need For Scientific Stardom & MONEY...
    Not Saying No. Just Allow The Greatest Minds Throughout The World To Give A Second Opinion- MONEY IS THE ROOT OF ALL EVIL. Am I The Only One Who Cares- The Devil Will Or Maybe Be Rubbing His Hands In Wait- let us Be Sensible Humans & Give This Project Just A Little More Scrutiny- Our Existence May Rely/Depend Upon It. I'm Not Being Alarmist- Chernobyl Was Described As SAFE-
    Reply
  • Gringoz
    admin said:
    Nuclear fusion reactor could be here as soon as 2025 : Read more
    The first efficient nuclear fusion reactor might also be here as soon as 3025, are you buying stock in 4 years from now
    Reply
  • OPTom
    Science indicates that greenhouse gases will raise the temperature of the earth, melt the ice caps, kill off many animals, and generally make conditions on earth unliveable for humans. Fusion, apparently clean, could stop the burning of carbon fuel completely. Whether we incinerate the planet, or, find a safe energy source is worth rolling the dice. The next asteroid may get us before this all happens anyway.
    You miss all the shots you do not take,
    Reply
  • Frankster
    True story. As a senior US Customs officer, I visited an internationally known company in San Diego as part of an importation of a vast, multi-million dollar electric power generating unit. It was explained that this power generator will generate electricity for experimental purposes - the local power supply had not this ability, *You know what nuclear fission is - A-bombs and all. Well, this is fusion, capturing the energy released by combining two atoms into one. The energy from a cup of coffee, captured by this process, could power all of California - even the entire West Coast." Astounded by this, I asked when this might be active. "A decade, maybe two" was the reply. This was in the late 70s.
    Reply
  • Chem721
    Wanda said:
    Is there some reason we want humanity to stick around for millions of years?

    Most of the plants and animals still alive would give that a thumbs down, Wanda.

    Quoting from the article:

    "Martin Greenwald, a plasma physicist at MIT and one of the lead scientists developing the new reactor. "We want to have an impact on society. We need a solution for global warming — otherwise, civilization is in trouble."

    In reality, civilization is already in trouble :

    - on-going mass extinction (we know this one is NOT caused by an impact or volcanism)
    - deforestation (they are burning down the Amazon rain forest to grow soybeans)
    - over-fishing has been going on for decades, with no end or moderation in sight
    - massive die-offs of coral reefs due to warming and acidification of the oceans by carbon dioxide is disastrous
    - rising sea levels are already causing severe damage to coastal forests via salt water intrusion (Ghost Forests)
    - rising sea levels are already causing flooding during King Tides in many places
    - rising sea levels intruding into many toxic waste dumps built at or near sea level will be catastrophic
    - warming seas already causing more frequent and more damaging storms
    - drought or flooding in many areas previously not prone to these extremes (results: large fires and storm-driven floods)
    - out-gassing of methane hydrates is accelerating in the arctic, as is the decomposition of the tundra for more CO2
    - sadly, this is the short list......

    People are always talking about net-neutral carbon emissions. We need a net negative on that carbon, and we are not even close to getting it.

    Even if the SPARC* tokamaks are ready for use in 2025, most of the developing world, the source of a great deal of green house gases, will likely not be able to afford them, or want to. And even if they can, building out the infrastructure will take many years. Even if they can get them operational and lower cost by 2025, the damage to the planet is on-going and extreme.

    The build-out time for these reactors to provide power everywhere will surely be long term. We do not have long term for a solution. Some would say it may already be too late. Time will tell, if it has not already.


    * https://en.wikipedia.org/wiki/SPARC_(tokamak)
    Reply
  • Skeptic185
    I don't think so.....nuclear fusion occurs in conditions that are so extreme, ie in the heart of stars of thremonuclear bombs i don't see how we have the technology to duplicate these conditions. Temperature: tens of millions of degrees, radiation cooling by gamma radiation quickly lowers the temperature. Pressure: Trillions of times greater than atmospheric pressure. Density of the plasma in the sun is 200 times that of water. The plasma is completely degenerate. We have never been able to create this kind of matter for more than a few microseconds. If not contained it would expand with the force of an H bomb. Don't see how these conditions can be maintained.......And the energy production per volume in the heart of the sun where this occurs is actually less than the energy generated by a compost heap!!!! Which implies a huge reactor......The fusion generating heart of the sun is 40,000 miles in diameter.
    Reply