Pumped-storage hydroelectricity is an excellent and renewable answer to this problem in tons of areas, has high efficiency (above 70%) and is already in use in a number of areas.
I loooove pumped hydro in theory, but it's so geographically finicky, you can't deploy it just anywhere. Particularly flat land, where the wind resource tends to be both plentiful and accessible...
But it's definitely one arrow in the quiver, and together there are solutions for just about any storage problem you can imagine.
Personally I think a big obvious shift is that EV chargers should be located in the places that the cars park during the day. The whole "charge at home overnight" thing is an unnecessary demand shift. Charge at work during the day, when the PV is producing like mad.
Even if the PV is on the roof at home and the power is getting shipped several miles over the grid to the office where the car is parked, it's still easier to move power over distance than to store it over time.
Of course PV on the roof at work would be even better, since commercial roofs tend to be broad and flat and boring. But it'll take quite a bit of forward thinking to unlock that cognitive step.
I’m completely happy if my dishwasher waits until the sun comes up to start. Or my dryer determines it’s a good idea to wait an hour before starting. Or if my XYZ charges super slow today because it’s not too windy. Or if my freezer goes into deep-freeze mode because...
I wish I got to pay the “real” price of electricity instead of lame time of day buckets.
That brings up a point. Current pricing models are based on old technology where you have coal fired plants that can't turn down. And meters that can't do time of use metering. Power is cheaper at night because you can't just up and shutdown a coal fired plant. Residential rates are flat
I really think a lot of night time load is just industrial customers chasing price. Change the price structure and they'll immediately adjust their time of use to match. Certainly smarter appliances could also chase low rates like industrial users.
Yeah but you wouldn't be happy that your incubator or AC didn't work when it needed to. You wouldn't be happy either if factories can't produce enough food because they would have to wait for wind or sun.
Pumped hydro is great for these circumstances and we absolutely should build it where it's feasible even though it's often considered anti-green due to ecosystem damage by the dam/reservoir.
However, as far as I understand, this is not a sufficient solution to the storage problem because you can't build them just anywhere; (a) the feasible locations are not enough to fill the enormous storage need required for a full transfer from fossils to wind/solar; and (b) in general, the type of locations that are good for pumped hydro (e.g. rivers on mountains) are not the type of locations where we have major cities (e.g. fertile plains) and mass production of renewables, so they are far from the major consumers and producers and we have a bit of a grid transit problem and international cooperation problem for that.
So while we build pumped hydro we still need to look forward to something else (e.g. mass battery storage) that can fill the gap between what we can store today and what we'll need to store to stop burning fossil fuels.
How applicable is this to large scale electricity storage? I don't have any numbers but I doubt you could power a large economy like the German one based on pumped-storage.
It's ok for some niche use cases but I doubt it's the future.
Lazy troll is lazy. You don't need to store your entirely yearly production. You need to store the difference between your daily production peak and your daily demand peak, and you only need to store it for that fraction of the day.
“You need to store the difference between your daily production peak and your daily demand peak”
Firstly, I would think the difference between production and demand on a single day is a better indicator than the difference between your daily production peak and your daily demand peak, which could be months away from the day production peaks.
Even that isn’t correct, though. Such a reserve buffer would be depleted after that worst-case day, so if the day after that day also has demand outstrip production, you’re in trouble.
You know, we have these things called gas plants... They burn gas and you can turn them off if you don't need them...
You can even generate the gas with excess renewables if you really want to...
If your goal is to store 100% of all power produced for an entire year for use a later date, then yeah... you would need 50,000+ of those.
If your goal is something not ridiculous, for example, storing storing the difference of production-consumption when production>consumption for use later when consumption>production, you would likely need very significantly less than 50,000+ of those.
Clearly you only need a small proportion of grid power in storage to cope with peaks.
There are also multiple ways to smooth load - overcapacity, battery storage, pumped storage, load shedding, pricing. These are solved problems which just need a bit more work and investment, and many countries already use pumped storage extensively.
The UK has had pumped storage since 1963, there are more planned around the world - this is neither exotic nor particularly hard, the only constraint is land, and as I mentioned there are multiple other solutions.
Scotland has already entirely met its needs with renewables this year. This can and will be expanded to other nations in time.
Oh, just a few oddballs nobody's ever heard of: Switzerland, Austria, Portugal, Japan, Spain, Italy, South Africa, Belgium, Ukraine, South Korea, Poland, France, Australia, Thailand, Germany, UK, India, US, China, Russia.
But it's definitely one arrow in the quiver, and together there are solutions for just about any storage problem you can imagine.
Personally I think a big obvious shift is that EV chargers should be located in the places that the cars park during the day. The whole "charge at home overnight" thing is an unnecessary demand shift. Charge at work during the day, when the PV is producing like mad.
Even if the PV is on the roof at home and the power is getting shipped several miles over the grid to the office where the car is parked, it's still easier to move power over distance than to store it over time.
Of course PV on the roof at work would be even better, since commercial roofs tend to be broad and flat and boring. But it'll take quite a bit of forward thinking to unlock that cognitive step.