Lockheed Martin has quietly obtained a patent associated with its design for a potentially revolutionary compact fusion reactor, or CFR. If this project has been progressing on schedule, the company could debut a prototype system that size of shipping container, but capable of powering a Nimitz-class aircraft carrier or 80,000 homes, sometime in the next year or so.
Tokamaks, a magnetic confinement device scientists in the Soviet Union first invented in the 1950s, as an example, stating that they had a low magnetic pressure limit under which they could safely operate.
With McGuire's help, the article succinctly explained, at least in theory, how the CFR was supposed to get around these issues:
“The problem with tokamaks is that “they can only hold so much plasma, and we call that the beta limit,” McGuire says. Measured as the ratio of plasma pressure to the magnetic pressure, the beta limit of the average tokamak is low, or about “5% or so of the confining pressure,” he says. Comparing the torus to a bicycle tire, McGuire adds, ‘if they put too much in, eventually their confining tire will fail and burst—so to operate safely, they don’t go too close to that.’ …
The CFR will avoid these issues by tackling plasma confinement in a radically different way. Instead of constraining the plasma within tubular rings, a series of superconducting coils will generate a new magnetic-field geometry in which the plasma is held within the broader confines of the entire reaction chamber. Superconducting magnets within the coils will generate a magnetic field around the outer border of the chamber. ‘So for us, instead of a bike tire expanding into air, we have something more like a tube that expands into an ever-stronger wall,’ McGuire says. The system is therefore regulated by a self-tuning feedback mechanism, whereby the farther out the plasma goes, the stronger the magnetic field pushes back to contain it. The CFR is expected to have a beta limit ratio of one. ‘We should be able to go to 100% or beyond,’ he adds.”
If the system works, it’s hard to underscore just how dramatically it could change not just the future of warfare, but the basic nature of human existence. Running on approximately 25 pounds of fuel – a mixture of hydrogen isotopes deuterium and tritium – Lockheed Martin estimated the notional reactor would be able to run for an entire year without stopping. The device would be able to generate a constant 100 megawatts of power during that period.
According to the company website on the CFR, the reactor could be powerful enough to run an aircraft carrier, power a plane the size of a C-5 Galaxy airlifter, provide electricity to cities with anywhere from 50 to 100,000 people, and maybe even speed up a trip to Mars. In each case, the compact reactor would take the place of large conventional fuel systems or fission reactors, eliminating weight and bulk. This in turn could create trade space for additional system or carrying capacity in terms of personnel or materiel or potentially allow for a more energy efficient overall shape or design.
