In my world, alien 'reactors' are discovered that are very efficient at creating power (around 1000x better than fission), as well as requiring little fuel, making them the perfect power source.
However, these reactors are not simple, no, they are advanced. Take nuclear fission for example. Nuclear fission can be defined by a set of equations, primarily $\ E = mc^2$ , such that with sufficient information (temperature, fuel quality, void coefficient, temperature coefficient, etc.), you can model how the reactor will behave for the next 100 years, to a high degree of accuracy. You can, for example, hook a simple computer up to a nuclear reactor, and have it set the control rods based on how hot the reactor is, and with enough conditions, luck and failsafes, it will never explode or stall*. The same is true for burning a fuel, nuclear fission, and most other types of power generation.
*Something might break within the reactor, or a meteor might hit the plant, but that doesn't count. I am not liable for any damages caused by trying to fully automate a nuclear reactor.
However, these alien reactors are different, they use some underlying mechanism that cannot be predicted at all, past a few milliseconds. The reactors, if simply started, will explode in less than a second, as they quickly destabilise. In normal operation, seen in the one functioning reactor, the power output oscillates seemingly randomly, never becoming dangerously high. Even in destabilisation, the power doesn't simply shoot up, it oscillates within the safe range, until it simply shoots up, destroying everything in a large radius.
To make sure that the output doesn't destabilise there are a few variables that are controlled, similar to the control rods in a nuclear reactor. For the purpose of the question, these variables can be anything controllable about the reaction, but they have to be given the correct values based on the current output in order to keep the reactor stable. The aliens used highly advanced computers to predict the correct values, but they won't turn on.
Its like if each of the control rods in a nuclear reactor were constantly, randomly, changing from high neutron absorption (good) to high reflectivity (bad), and you need to tell, based on whether the power is rising, if you want them in or out, and react to that before the thing explodes. Also, any two reactors will have behave completely differently, even when close to each other and physically identical.
My question is, what mechanism could they be using to generate power? What is making it so unstable?
- Power fluctuates based on control variables
- Control variables affect the power level randomly, but this changes with a gradient so that they can be predicted a few milliseconds in advance
- If the power level is not regulated, it will explode
- Control variables can be anything, temperature, shielding, how much fuel you give it, etc.