I was just part of a tour group in the Hall of Justice (the new one in Washington, DC, financed by Batman) when I happened to overhear an intercepted message: Sinestro was deploying a device that would render all magnetic field on Earth useless.
Since we generate electricity by spinning turbines by various means that turn magnets around a wire, I am wondering what options we’ll have. Solar power? Steam engines? Any other way to make electricity that don’t rely on magnets?
You talking magnet magnets (how do they fucking work anyway?) or magnet magnets AND electromagnets?
Chemical batteries, thermocouples, photoelectric cells, piezoelectric devices.
You could harvest some electric eels and catfish, maybe.
Perhaps we could all just rub balloons on woolly clothes or our hair?
There are direct heat to electricity (thermoelectric generators) but they are pretty in-efficient.
photovoltaic is better, but I have no idea do these processes rely on magnetism at some level? I’m guessing that any change to physics that meant no magnets would break so much else that we can’t really talk meaningfully about what would work.
And don’t forget the lightning farms.
I think the idea is that magnetic fields are all hosed.
That means no motors or transformers either.
Old-timey generators used to work using friction. So this is actually feasible (though I doubt it would be anywhere close to as efficent as turbines).
Not necessarily. Steam engines, Stirling engines – those should work fine. In fact, an internal combustion engine that relied on electricity produced by thermocouples should be possible.
Since the electromagnetic force is only one unique entity, the hypothetical scenario that magnets down work anymore means that there is no electric field either. In fact since one out of the four fundamental forces of the universe no longer exists probably all matter in the universe would collapse into black holes (though dont quote me on that).
Photovoltaic cells come to mind as the most practical (hint: not practical at all). Nuclear power plants can directly create electricity too, I think. Or are they just used to make steam and spin a turbine?
Friction is right out.
Forget piezoelectric effect too, at least for now. Maybe some futuristic water wheel or tidal energy could get electricity efficiently this way, but nothing we know of would gather any useful amount.
Plus birds will get lost.
While there have been (small) generators that convert the heat from a nuclear reaction directly into electricity, your typical nuke plant used for large scale power generation uses the heat from the nuclear reaction to make steam, which is then fed through steam turbines to spin the generators. The only major difference between a nuke plant and a coal plant is what heats the steam.
Okay. Off the top of my head the best bet is thermoelectric (different metals in contact producing electricity in the presence of heat). Thats going to be something like 10 to 100 times less effiecient than a modern power plant.
Ditto. Electricity and magnetism are ONE force, inseparable. eliminate one, you have eliminated both.
Or, if you prefer, they are two ends of the same singular whole. You still can’t eliminate part without eliminating all.
Just for clarification if something is a ‘motor’ it is electric. ‘Motor’ is often used incorrectly to describe various ‘engines’
A motor would not work without a magnetic field
You would think General Motors would make more electric cars.
Given the scenario, life as we know it will come to a grinding halt. We have no means to distribute electricity on the scale necessary even if we could find alternate means to create it.
I think we’d better let Magneto handle this one.
Given the hypothesis is pure fantasy, you’d have to imagine separating them is possible through pure magic.
I get the fantasy part, but the premise is along the lines of “what if gravity only applied to living objects?” Either eliminate gravity or not. Don’t try to make it split along lines that have no relation to mass. 
This is why I don’t get hypothetical questions. Given the hypothesis is pure fantasy, the only honest answer is that anything is possible.