Accumulators: A concept for GURPS Spaceships

[Kale]

Getting back to Accumulators, it seems the only pseudo-realistic tech that makes sense is superconducting loops. Anything else requires a fair bit of handwaving to explain the energy density and discharge rates. I also wonder if star-trek style plasma could do the job? Maybe store the plasma in rings and draw the power down as you need it. Could use superconductors to help with efficient confinement of the plasma to generate containment fields...?