Infinite, virtually free, clean, energy could become a reality within the next 15 years.

Image credits Slaven Olcar.

The long-held dream of nuclear fusion power generation is right on our doorstep, according to a joint project between a private and MIT researchers. If successful, this project could fundamentally change the way and produce energy.

The program took a radically different approach to the task compared to most similar efforts. The team intends to use a novel class of high-temperature superconductors. They believe this change will make the first net-energy-positive fusion reactor in the world a reality.

Too much buck, not enough bang

Fusion is the merging of two atoms into a heavier one; the opposite process, called fission, is what happens in a nuclear bomb. Like in a nuclear bomb, fusion reactions also release a huge amount of energy. Usually, this is done using the lightest atom out there, hydrogen, to produce helium. The problem we currently have with fusion reactors isn’t that the reaction can’t be tamed. We have been capable of maintaining a fusion reaction since about the 1990s but what we can’t do, however, is maintain a fusion reaction and get energy out of it; you know, the thing stars have been doing since almost forever.

Unlike a star, engineers can’t rely on sheer mass and gravitational pull to keep everything tidy. Also unlike a star, we need to get the reactionary matter, plasma, at higher temperatures than that in the core of stars — so we use massive magnetic fields to keep the plasma contained, lest it burns through the reactor like lava through butter. Generating those magnetic fields and all other energy drains required to run the reactors currently makes fusion a net-energy-negative affair: we have to put in more energy than we extract to keep it going.

That hasn’t distracted researchers’ eyes from the prize, however. If we can indeed maintain a fusion reaction like those going on inside a star, it would essentially mean more clean, virtually free energy than we’d know what do do with.

“The aspiration is to have a working power plant in time to combat climate change. We think we have the science, speed and scale to put carbon-free fusion power on the grid in 15 years,” says Bob Mumgaard, CEO of the private company Commonwealth Fusion Systems.

Mr. Mumgaard has attracted $50 million in support of this research effort from the Italian energy company Eni in the hopes of getting such technology going. The usual timeframe given for feasible fusion today is 30 years in the future, but the MIT team say they can cut that time down by half if they use the superconducting materials to produce the ultra-powerful magnets needed for the reactor.

The new material — a compound dubbed YBCO, from yttrium-barium-copper oxide — will be used to coat steel tape, creating much smaller but more powerful magnets than currently available. This would potentially reduce the amount of energy required to jump-start and maintain the fusion reaction. As a rule of thumb, the stronger the magnetic field, the more compactly the plasma can be squeezed, which makes it more likely to generate stable fusion.

The experiment, known as Sparc, aims to use these magnets to create a much more compact reactor, about 1/65th the volume of the International Thermonuclear Experimental Reactor (ITER) project, currently being built in France. The net output should is estimated to be twice the amount of energy fed into the system. To give you an idea of what that means, this comparatively small reactor should provide about 100MWh of heat — which, converted to energy, should be enough to power a small-to-medium sized city.

Another advantage of fusion energy is that, unlike fossil fuels or nuclear, it uses a virtually impossible to run out of the fuel it uses — hydrogen. There aren’t any greenhouse gases released in the process, and fusion doesn’t generate any radioactive waste products.