Storing Energy Bleg
Robert Waldmann
I am eager to learn from this blog again. A problem with solar and wind generation of electricity is the sun isn’t always shining and the wind isn’t always blowing and it is costly to store energy. I don’t see why energy can’t be stored using hydroelectric dams. They store huge amounts of energy in lakes. So what’s the problem. More thoughts after the jump.
OK problem number one is that the hydroelectric plants are where they are not where we want electricity. This means that a national power grid which doesn’t waste energy would be needed. I think that means very high tension direct current.
Such capacity would also be needed to use wind power much at all as the windy states are sparsely populated. I assume the problem is solvable and that the cost is not prohibitive.
A second problem is that the peak capacity of hydroelectric power plants would have to be increased. If they build up water during the day and release it at night, then they have to be able to convert the large flow to electricity. Dynamos would have to be added in some way. Now I Imagine that this can’t be all that costly. I think of a huge siphon or a tunnel or a channel. Am I demonstrating my ignorance of engineering.
The H2 O2 concept has a serious efficiency problem along with storage problems. Electrolysis itself has an efficiency of 70%, then fuel cells are around 60% if you’re lucky so right there we’re down to 42% of the energy we started with. But then on top of that is the storage of hydrogen which as a gas is the least dense fuel source on the planet, so cooling and condensing it to liquid hydrogen causes a further lose of energy, then for saftey reasons cars have to leak a small amount of hydrogen over time losing even more of the fuel.
I say this to keep people thinking, but just not wasting their time thinking about hydrogen. There are other solutions and I hope we’ll find them.