I have floating islands with varying levels of technology that can be allowed on them, usually based on height. One of these islands has tiny microbe/bacterium that allows for food crops to be grown at a reliable rate on these islands but at a cost. It's a green goo (alternative to grey goo in which tiny nanites attack electrical applications). It relentlessly targets electrical applications (completely ignores bio electricity). Creating a vacuum or sealing away a computer offers no resistance due to handwavium reasons. Basically, if it detects an electricity in a certain way, it's going to attack it. When attacking an electrical application, it reproduces rapidly spreading like a cancer and dissolving the wiring and metal frame of whatever its spreading on. The effects are almost immediate as well.
Yet at the same time it allows things like vehicles, tanks, aircraft, basic electromechanical computers/machines and small-scale electronics to work. Most of these are things that will utilize electricity in some way, but often through a battery. As such their use time is limited and dependent of batteries. In a sense electrical technology is grounded to that of the 1940s or even worse in some areas in terms of portability (vehicles count as portable in this sense).
What should my green goo target to disable electrical infrastructure but allow smaller scale electronics?
The goal is to have an island where power generation isn't feasible, especially for large scale devices. Things like large factories, long distance power cables, radio towers etc do not work. But something simple that can be run off a battery works. The absolute max for a battery is the size of a car or airplane battery.
There exists more modern technology on other islands, but if they bring that technology down to the island that requires electricity in any capacity more than a battery, then the system bricks and the green goo attacks the machine.
- Integrated circuits do not work on the island except for aircraft flying at reasonable height and speed. Airships mounting a modern computer will short out/be infected by default. This isn't part of the scope of the question. It's already been taken care of. So IC's and semiconductors can be ignored.
- The green goo dies the moment it leaves the confines of the islands. Think of the area of effect as a dome.
- All wireless communications on the island are jammed past a short distance due to the microbe/green goo
- Bio electricity is completely unharmed.
- Chaining multiple batteries together should cause issues/isn't allowed.