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.
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.
We could all probably do well eating a little less factory-produced food and a little more farm-produced food.
You can spend some of the money you'd otherwise save on electricity in those cases.
> You wouldn't be happy either if factories can't produce enough food because they would have to wait for wind or sun.
A factory shifting hours wouldn't be noticeable at all by the time the product reaches the consumer weeks later.
If the factory isn't running enough hours at all, that's not a problem caused by renewables being unpredictable. That's just bad management.
But more realistically you'll be able to pay more per watt for that short period and get as many amps as your house can handle.
But also, buying such a variable-price contract is only going to be an option. If you want a certain amount of guaranteed-price power, as an individual household, there will always be someone willing it to you.
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.
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.
It's ok for some niche use cases but I doubt it's the future.
...can supply a maximum power of 1,728-megawatt and has a storage capacity of around 9.1 GWh.
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.
1. Small population.
2. Pretty tall mountains and sparsely populated mountains (see 1.)
3. Quite high yearly rainfall levels.
4. Very rich country.
5. Country with a very low level of corruption and from what I know, pretty efficient at building new infrastructure.
Is there an example of an "average" country having decent levels of pumped hydro storage at a level that's above 0.5% of the country's needs?
According to https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
Scotland has already entirely met its needs with renewables this year. This can and will be expanded to other nations in time.
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.
For your average country even having 100 is difficult. Think of some flat place like Poland.
More than that, Germany isn't even the biggest producer/consumer of electricity... Imagine some place like China trying to ramp this up.
Try harder, please.
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.
Although, at some point it could be easier to just build coastal lagoons and let the tide do the work.