How a giant battery may save the world (osmium & irw)

[popcorn_karate]

Originally Posted by cragger

You miss the point of the "x 30 days" in the calculation.

or perhaps you missed that you would need a 180,000 gallon tank to run it for 1.5 hours each day of the month as you suggested?

Originally Posted by cragger

Using the example of solar generation, you would re-fill the upper water store every day using solar power. You need to store enough energy to get you through to the next generation period, not build up a month's-long store at once. Looking at things on a month long scale just seemed to be useful since we typically get electric bills on a monthly basis, so there is a little "feel" to that sort of timescale.

This neglects extended periods of bad weather/no wind or whatever of course, just back-of-the-envelope stuff that shows theoretical potential, though not necessarily at a $/kWh cost that is attractive. On the other hand, a large energy store using current deep discharge batteries isn't what you would call cheap either.

This leads to the point Osmium was alluding to in looking at this as a grid-level question. Like many things, a cooperative approach is likely the most efficient. I favor a hybrid system, with millions of small points of power generation going down to the home level, combined with large generation sources on the grid as well - dams, wind farms, wave power, etc. once the inevitable transition to renawables happens. I would envision the majority of storage for load leveling would be at scales above the home.

Afterthought: one readily sees that combining the functions of conventional dams with the addition of recycling of water as energy stores provides obvious synergy as a very efficient partial solution.

agree with this stuff. distributed energy generation and storage is where we need to be going.