Comment by vidarh
10 hours ago
The problem is where to store it.
10 billion liters of water is 1,000 m^2 * 10m deep. There is no suitable location for that that is both elevated enough and near enough to Mjøsa to be financially viable.
Norway also existing hydro reservoirs with a capacity equivalent to around 6-8 months electricity supply, so it's not really a major need for Norway, anyway, but this is a fairly general problem: Finding suitable locations that are close enough to a water source, and provides a large enough potential reservoir is hard.
> Finding suitable locations ... is hard.
No it's not. Here's almost a million of them: https://re100.eng.anu.edu.au/global/
If big ones are hard, you can make a bunch of smaller ones.
Looking at a few of them, a few obvious problems are apparent.
Firstly, it takes a rather liberal idea of how close the basins need to be to each other to be viable.
Secondly, most of the ones I looked at would require extensive relocation of existing populations and/or large-scale infrastructure changes, such as re-routing important roads.
The first few I looked at also do not have a sufficient water supply nearby - you'd face either covering them or you'd quickly run into problems of evaporation that you have little ability to replenish/replace.
A lot of the ones I quickly looked at would also face "fun" issues such as no nearby infrastructure such as roads to bring in construction materials.
I have no idea how many suitable locations there are on that map, but it seems pretty apparent it is a small fraction of the ones marked before you even consider how many would be politically unviable because of public resistance to the environmental destruction.
To be clear, I'm not at all opposed to investigating pumped storage, but it's also not nearly that simple.