Nuclear fusion has taken a big step forward

Good news in the energy community. So good, I am breaking my blogging break.

If you were paying attention to the news the last couple of weeks, you may already know this. The United States Department of Energy (DOE) and DOE’s National Nuclear Security Administration announced a major scientific breakthrough in nuclear fusion achieved by scientists at Lawrence Livermore National Laboratory (LLNL). For the first time ever, the team at LLNL’s National Ignition Facility (NIF) in California achieved a net energy gain, meaning the reaction produced more energy from fusion than the laser energy input to drive it. The experiment successfully produced 50 percent more energy than what was consumed by the lasers. According to the DOE’s announcement “LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output…”

Nuclear fusion has been in the works for over half a century, but experiments in reactors always took more energy to achieve fusion than the energy resulting from the reaction; so, the news from the LLNL is a big deal. A big step forward.

Nuclear fusion (in contrast to fission) is the merging of small atoms into larger ones. The collision and fusion of those atoms releases enormous amounts of energy in the process. It has often been seen as a “holy grail” for clean energy. Among its advantages nuclear fusion produces more energy than fission; there is no risk of nuclear meltdown, nor does it produce any long-lived radioactive waste; and it has zero emissions. It sounds like the perfect clean energy. But is it? Some members of the scientific community would like to remind us that it could take at least 25 years (being optimistic) to see a commercial nuclear fusion reactor come online. Additionally, there is also another type of safety issue regarding laser fusion, especially as a component of a fission-fusion hybrid reactor, and that is the production of neutrons that can be used to produce nuclear explosives, which makes sense as the DOE’s announcement emphasized the “advances in national security” first, and the “future of clean energy” second.

What is next? Even though NIF’s achievement is significant in showing that a controlled nuclear fusion reaction can be potentially self-sustaining, there is still so much work to do. The experiment was done on a small scale producing only the equivalent to 0.9 kWh. The input energy from the lasers mentioned above (2.05 MJ) does not even consider the 300 MJ that the facility needed to create the laser beams in the first place. With that knowledge, we know we still face many challenges to make fusion into a practical, safe, and abundant source of energy.

In the future, decades from now, nuclear fusion will potentially deliver the carbon-free energy source that we dream of; but it might be too late to the party once it is ready for commercial production. For the moment, nuclear scientists need to continue researching fusion to increase the output to input ratio. This task will fall into the hands of the International Thermonuclear Experimental Reactor (ITER) which is scheduled to begin operations in 2025.

At the moment, the climate emergency continues to be a major issue for our planet and livelihoods. But because of the urgency in trying to limit temperatures rising at 1.5°C above pre-industrial times, which involves reducing CO₂ and other greenhouse gas emissions, people in government and environmental science are starting to consider nuclear fission again. Climate goals, an increased number of severe weather events and prolonged droughts, and the Russian invasion to Ukraine have brought an increased acceptance of nuclear (fission) power around the globe including places like California, Germany, and other parts of Europe.

While we wait for nuclear fusion, we already have fission; and even though it has many drawbacks, it still is a source of abundant electricity with no carbon emissions that operates safely under most conditions.

Sources:

U.S. Department of Energy, Washington Post, The Guardian, The Hill, The Energy Gang Podcast

Featured image: Thehill.com / Lawrence Livermore National Laboratory via AP