[berntb]

Solar can certainly solve the energy problems for many countries, given that cheaper energy storage really is created. But not for e.g. northern Europe. There just is too little sun, especially in the winter.

Also, it seems transports will be radically electrified the coming two decades, which will strongly increase the demand for electricity.

I have no problems with environmentalists, my problem is that so many of them rather burn oil than build nuclear plants.

[paulmd]

Solving energy storage on that level is a non-trivial task. People don't understand just how energy-dense liquid and solid fuels are, but you essentially need geological-scale solutions in order to replace them (pumped-storage hydro or compressed-air in deep caverns). Those require specific geological formations and in the case of pumped-storage hydro has a pretty negative environmental footprint. You take a mountain range and you flood it and drain it on a daily basis, anything that used to be there is now underwater half the time.

https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

There is about 740 TWh of pumped-storage capacity available worldwide. If we gave every single US household a Tesla Powerwall (6.4 KWh) it would add up to 0.7936 TWh of capacity. If we keep the US average of 2.55 people per household and scale that up to the 7.4 billion people worldwide (2.89 billion households) that's still only 18.49 TWh. One per person worldwide, 44.8 TWh. Maybe double that if we give every person on the planet an electric car that's tied into the grid too.

So if we gave every person a Powerwall, that's 6% of the presently extant pumped-storage capacity. And it's certainly not like we've made any sort of systematic attempt to fully exploit pumped storage, if we are doing worldwide solutions then we can go a lot farther on the other side of the equation too.

Again, people vastly underestimate just how great liquid fuels are at storing energy in comparison to how shitty batteries are. We're talking about liquid fuels having more than 100x the energy density of a lithium-ion battery here. Batteries are convenient from a design perspective but they are wildly inefficient from a density perspective.

https://en.wikipedia.org/wiki/Energy_density

If anything, the advent of cheap clean electricity from nuclear should shift us toward synthetic liquid fuels for the energy density involved. There's nothing stopping you from pulling carbon out of the air and synthesizing it back into a long-chain hydrocarbon. It's also significantly cleaner than fossil-derived fuel.

The Fischer-Tropsch process has been around for a century and there's lots of neat modern tweaks to it. It just takes a lot of energy (more than you get out of it obviously) but if we have lots of nuclear power then why not use it as a dense energy-store over batteries? It saves us a heck of a lot of rebuilding infrastructure too.

[skrause]

> But not for e.g. northern Europe. There just is too little sun, especially in the winter.

Norway is already 99% on renewable energy because of hydropower: https://en.wikipedia.org/wiki/Renewable_energy_in_Norway

There's also plenty of wind. Solar is not your only option.