The capacity to store power (not merely make it with more common elements) is a fixed limit. We already have an idea what that limit is.
To quote Dr McCoy, "It's worse than that, Jim".
The amount of matter required to store
or generate electricity is limited by the energy density of the materials used, which is in turn limited by the fundamental forces that we are manipulating.
Wind* and hydroelectric power use gravity as their source of energy (or as a storage medium in the case of pumped hydro). Gravity is pathetic**, so huge volumes of material are needed; But gravity leaves that material effectively unchanged, so on the plus side, pollution is minimal. Nevertheless, it requires a LOT of air or water to make electricity from these technologies, and while both are pushed around by sunshine and are pretty abundant, this still implies a lot of concrete and steel, and often expensive high tech materials to capture and convert that energy.
Combustion, battery storage, and photovoltaic generation, use electromagnetism as their energy source; They move electrons between atoms to extract energy from those atoms. In PV systems, the electrons are stripped away from their host atoms by sunshine, and allowed to drop back into place; Sadly, sunlight isn't very energy dense, and doesn't happen at night, so you need a lot of fairly exotic materials to get not very much electricity. Chemical energy can be quite dense, but ultimately it's limited by the energy available in the electron shells of atoms, which sets a lower bound for the amount of matter required per unit of energy. This is why battery storage is incapable of ever working at grid scales - it requires a vast amount of whatever you make your batteries from, even if you can use the entire energy of all the electrons in the material (you can't even get close, though we are vastly better at it now than we were a few years ago; That improvement has a hard physical limit to it). Chemistry also changes the arrangement of the atoms, leading to the creation of new molecules that you then need to dispose of. And because the energy density is quite low, you get a LOT of these compounds, and managing them is a major challenge (which we historically "solve" by pretending it's not there and walking away with our hands in our pockets, whistling).
The Weak nuclear force is difficult to exploit. Some small power sources for little devices with specific needs (such as cardiac pacemakers) use it; And Radiothermal Generators have been used in remote locations (including space exploration) to good effect, but it's never been scaled up to national grid levels, and likely never will, as the materials used are scarce, expensive, and while they store a very large amount of energy, they release it rather too slowly to be really useful for bulk electricity generation.
This leaves the Strong nuclear force. Fusion power is about sixty years away, and always will be. It's sole major advantage over fission power is that it doesn't upset the neo-luddites, on the single and simple grounds that it doesn't exist. If someone developed a working and practical grid scale electricity generating fusion reactor tomorrow, doubtless the antis would suddenly discover that its components become radioactive in use, due to neutron bombardment, and would immediately declare that they must not be built "until there's a solution to the waste problem", a movable goalpost that is synonymous with "ever". So we're left with fission. It's the only way to make a lot of electricity, without using a lot of resources. And ultimately, that should be our objective, both for environmental and cost reasons.
If you want to make as much electricity as possible with as little environmental impact, and as little resource use, as possible (and I think we do), then fundamental physics says that you should look to nuclear energy; and the current state of our engineering abilities says that fusion is not coming yet in planet Earth, which leaves fission as the front runner.
*Wind power ultimately results from solar heating of the atmosphere which sets up convection currents in the air - it's gravity that makes the denser cold air fall, and thus makes the less dense warmer air rise. This rising and falling air then moves laterally due to the Coriolis effect as the planet rotates, and to a lesser extent due to the movement of the points of maximum and minimum solar heating (midday and midnight), also caused by the rotation of the planet.
**Gravity is so pathetic that the gravity of a 6x1024kg planet can be overcome by the magnetic field produced by a 1g fridge magnet.
