Can you make devices that produce and use electricity like power supplies, motors, light bulbs, etc. in a society without metal? Not just metal isn't in the device, you can't even use metal in the production process.
Edit: There is enough trace metals for human biology to work, but not enough for metallurgy. Could static electricity generators(made from just rubbing, so metal not needed) or electric fish become feasible power supply replacements for batteries?
Practically no, theoretically maybe. That theoretical maybe is, when you already have non-metallic electricity conductors and batteries available. But it is impossible to have non-metallic electricity conductors and batteries without first having metallic conductors and batteries.
Apart from the practical issues about devising precise and accurate things such as an electric motor (all electric generators are just motors, used in reverse direction), you also have a serious epistemological issue.
How the heck do those people (living in metal-less world) get an idea of electricity and magnetism in the first place? Here on Earth, folks have been able to build primitive electric motors because magnets exist naturally and so do metals. It was also a natural observation that turning an electricity conductive coil (always made of metal, in the experimental days) in a magnetic field induces electric current in that coil. Devoid of metals and natural magnets, your people would never get any idea about electricity or magnetism at all.
Science is primarily based on the study of natural phenomena. In a metal-less world, there would be no natural phenomenon hinting at flow of current and magnetism, so there would be no idea about things such as conductance or motors or coils at all.
It is impossible to generate and use electricity when you do not know what electricity is, in the first place.
To make electricity you need to run an an electric conductor through a magnetic field. There are plenty of non-metallic conductive materials. The trick is the magnetism. To get the "bootstrapping" current to get a generator going you may need to use batteries for the magnetic coils. Non-metallic batteries are possible, just not as easy as metallic ones.
You can make machines out of things other than metal, but you will be limited as to how hard you can run them compared to metal.
I'll briefly address three common concerns when it comes to electricity:
If they have access to salty water, which conducts electricity decently, they could perhaps use water "pipes" to conduct electricity. Through years and years of experimentation and improvements, I imagine they could get at least somewhat effective pipes.
Electricity can also be generated from friction. It is easy enough to create a purely mechanical device that would cause something to rub against something else.
There's also other, more biological, examples of electricity harnessed from potatoes, lemons, etc.
I would rely on some biological element, again, to store the potential.
As for your light bulb example, nature already has bioluminescence (not through electricity, though). Just keep thinking out of the box, verrrryyyy out of the box ;)
Graphite conducts and is a natural mineral. So does charcoal to some degree, and eventually graphene and nanotubes.
I think they would work with biological materials and discover ways to treat and preserve tissues that act as electric components, and then mimic them with more synthetic forms.
Look at the experiment with the dead frog twitching. If the metal in the experiment was rare and expensive so wires and probes were not commercially practical to develop, he would have focused his attention on the dead frog.
Electricity and magnetism are both present in biology (eg, see Biomagnetism and Bioelectromagnetics) .
Organic computers (brains) and machinery (muscles) and energy storage (food/electrolytes) are all around us.
Non-metal conductive and non-conductive materials exist in gas, liquid and solid states (eg, water, ice, silica). Capacitors can be made with oil.
The main issue is predicting the difficulty of bootstrapping scientific discoveries in biology without scientific knowledge and equipment based on relatively simpler metal-based technologies. You might be able to replace simple tools like scalpels with sharp mineral-based objects (ie flint, ceramics, plastics) but how do you invent the stethoscope, or heart-monitor, or electrical probe, or wires or any number of tools used in biology that currently require metal?
My feeling is that given enough time a scientifically curious race would develop sophisticated bio-machinery as an offshoot of primitive breeding and genetic technology but would probably require at least 50K years to get there. If you want a real twist you could even argue that humanity or Earth itself is the product of such technology seeded by an advanced biotechnological race with space flight and extreme longevity.
God this sounds like a horrible way to develop electricity. First of all, it's nearly impossible to harness and use electricity without any metal. You can conduct electricity with carbon or silicon, but generating it would be honestly near impossible on any meaningful scale.
If you use a loophole like salts to abuse sodium and lithium, you may be able to at least produce something, though it's definitely going to be very difficult. Maybe you can use bone powder as calcium and lithium salt along with silicon to make a makeshift battery, though I'm basically guessing at this point. Turns out metals are so good at doing what they do that we don't typically mess around with trying nonmetals.
If you can somehow get your battery working you can make an electromagnet, and now you're capable of making a generator. Only instead of having the electrons provided by metal, you have something idiotic like salt water filled pipes that you have to try and generate an electrical current with. Maybe silicon or carbon would work better than salt water, but again, so little research that I can find that I straight up can't tell you for sure.
Anyways the point being is it isn't disproven yet, but the components are all so vastly inferior and hard to identify that a society with no free metal at all would most certainly never develop it. They would be hard pressed to even develop something like a steam engine, given how metal is our go too material for making it. maybe someone could do it with shale plates and wood tubes and rubber stoppers, but it's not going to be very efficient and will take a long time to harness efficiently, if it ever happens.
