Scientists experimenting with fusion energy at a lab in California last week reached a huge milestone on a journey that began more than 70 years ago at a lab in New Jersey: They created a fusion reaction that produced more energy than it took to create.
The significance of the breakthrough, which was announced Tuesday, cannot be overstated.
Simply put, the scientists reproduced the power of the sun in a laboratory using lasers — offering a glimpse of a potential future source of safe and plentiful clean energy that could have a dramatic impact on energy use and, therefore, climate change.
Don’t expect that to happen overnight.
While it took 71 years to reach this milestone — which was the goal when the federal government authorized the creation of what is now known as the Princeton Plasma Physics Laboratory in 1951 — it is just the first step in a journey to the ultimate goal.
ROI-NJ turned to Andrew Zwicker, the head of strategic partnerships and public engagement at the PPPL, and a state senator from the area, to help us break this down.
ROI-NJ: Let’s start with some teaching: What is fusion energy?
Andrew Zwicker: It’s energy that is created when you combine or ‘fuse’ hydrogen into helium. It’s what happens naturally in the core of the sun. Fusion is the ultimate source of energy — clean, safe, practically unlimited and carbon-free. It is the opposite of fission, which comes from splitting of an atom and it doesn’t have any of the safety issues — it can’t explode, it can’t melt down and it doesn’t have the long-life radiation that is harmful to humans and the environment.
Fusion has long been considered one of the great technological challenges, because it’s really hard to do. The sun and the stars do it in outer space; we’re trying to build a machine that can do it on Earth.
ROI: Talk about these machines: How do we re-create something that happens on the sun (fusion) on Earth?
AZ: There are two ways to re-create the process. One is to use lasers, which is what they did in California. They used short bursts of laser light (from 192 lasers) to compress a tiny capsule of fuel (a small cylinder about the size of a pencil eraser that contains hydrogen) and reaches a very high temperature. This created small explosions of energy.
The other version is what we do here at Princeton. We build machines that re-create the conditions of outer space inside them. They’re like giant metal donuts surrounded by very powerful magnetic fields. Inside the metal doughnut, we are heating up hydrogen gas to hotter than the core of the sun and using the magnetic fields to hold onto the plasma that we’re creating.
The result that happened last week in California marked the first time that a fusion experiment made more energy from fusion than the laser energy that went into it. There are a bunch of caveats to that statement, but all of the experiments that led up to this point consumed more energy than they produced.
ROI: What are the caveats?
AZ: The energy needed to power the laser beams was much more than the energy from the lasers that went into the fuel. So, in other words, it took much more energy to turn these lasers on.
But, regardless, the energy that came out of the plasma was greater than energy that went into it. No one had ever done that before. That’s the big achievement. And it’s a big one. And it’s a huge step. But, this is not the last step in any way, shape or form.
ROI: How long will that take before this process can be scaled to a level of significant impact: Another 71 years? Or is it seven years? Or seven months?
AZ: We know it’s not months, because, even if it was all solved, it still takes years to build power plants. The question is: What do we need to do to get the next breakthroughs in time to make a significant difference to combat climate change?
ROI: And the answer would be?
AZ: It’s all hands on deck — universities, national laboratories and the private sector. And the good news is that you’re already seeing billions of dollars being spent now by the private sector. This achievement will lead to more.
Fusion vs. fission
What is the difference between fusion and fission, which fuels our modern-day nuclear plants? Both fusion and fission use atomic energy, but there are a number of key differences between the two processes:
- Fission releases energy when atoms are split, while fusion releases energy when atoms are joined;
- The fusion reaction releases more energy than fission;
- Fusion doesn’t produce harmful long-term radioactive waste as a byproduct like fission does;
- Fusion needs more energy to accomplish its goal than fission does;
- The energy required for fusion has been a barrier to its widespread use for energy generation.
In the beginning, fusion research was all government funding. But, recently, we’ve seen a influx of private investment. That will shorten the timeframe as we move towards commercialization of fusion energy.
ROI: Is it a matter of the government stepping up — as it did during the race to the moon or the race to find a COVID vaccine? Or will it take money from a billionaire, say, Elon Musk, Bill Gates or perhaps Princeton grads Jeff Bezos or Eric Schmidt?
AZ: I’ll answer that this way: I think there’s a strong argument to be made that now is the time to accelerate this, and we see that happening already. There was a White House summit on fusion earlier this year, where it announced three new initiatives, including the development of a strategy to accelerate the realization of commercial fusion energy; a Department of Energy initiative to accelerate the viability of commercial fusion energy in coordination with the private sector; and $50 million in funding to advance the science for a fusion pilot plant.
The goal is not just to have fusion to make electricity, but doing it in a timeframe that will have an impact on climate change — have an impact on slowing down the amount of carbon we’re emitting into the atmosphere before it’s too late.
ROI: Let’s talk about a world where fusion energy is prevalent: What does it look like?
AZ: Fusion is not going to replace solar or wind or any of the other renewable energy sources. It’s going to be a baseload complement to them. The good news is that, once we figure it out, we’ll never run out of it. But it’s not easy to produce.
While it happens naturally in stars, it doesn’t happen naturally on Earth. We have to force it to happen. But it’s safe. It doesn’t produce greenhouse gases. And if something goes wrong, then Mother Nature takes over and it cools down and the reaction stops. It can never run out of control. The chain reaction we worry about with fission — anything that knocks out some of the safety systems, such an earthquake or a tsunami — we don’t have to worry about.
Fusion is something that can change the planet forever.
ROI: And perhaps that all can happen in New Jersey — wouldn’t that be fitting?
AZ: Absolutely. This all started here. Some 70 years ago, Princeton University professor Lyman Spitzer was asked by the United States government to set up research that was studying whether or not nuclear fusion could become a source of clean electricity.
The lab that he created in a farm field in Plainsboro is now the Princeton Plasma Physics Laboratory.
I would love to see us eventually talking about building the first United States fusion power plant right here in New Jersey. This started in New Jersey, we should complete the circle here.