Researchers from MIT are working on a design for a compact version of a tokamak fusion reactor. Their objective is to produce a practical fusion power, which could offer a nearly inexhaustible energy resource in as little as a decade. The new fusion reactor, ARC, would take advantage of commercially available superconductors; specifically rare-earth barium copper oxide (REBCO) superconducting tapes. These superconductors produce stronger magnetic field coils, which make it possible to produce the working material of a fusion reaction in smaller device than those previously envisioned. The reduction in size makes the whole system less expensive and faster to build. The new reactor is designed for basic research on fusion and also as a potential prototype power plant that could produce 270MW of electrical power. The researchers estimate that the new design would allow for removing the fusion power core from the donut-shaped reactor without having to dismantle the entire device. In addition, the superconducting magnets would enable the reactor to operate in a sustained way, producing a steady power output. Another key advantage is that most of the solid blanket materials used to surround the fusion chamber in the reactor is replaced by a liquid material that can easily be circulated and replaced. The current design should allow the reactor to produce about three times as much electricity as is needed to keep it running, but the design could probably be improved to increase that proportion to about five or six times. Thus far no fusion reactor has produced as much energy as it consumes.