Engineering360: "Energy Storage Wars: Which Technology Will Prevail?"

Good article with coverage of several different energy storage schemes. Pumped hydro seems to be the most cost effective method that provides ample power delivery and energy storage capability, but is also highly location dependent.

Just think about how many terawatt-hrs could be stored in the Yosemite Valley?

I agree. But, I still prefer liquid systems over solid systems, because it's easier to get low friction and low maintenance out it.

At least it seems that way. I didn't really research it that much.

Solid systems can use denser materials and be more compact.

Which is better? I don't really know. But, I would like to know that someone considered these factors.

The biggest problem I see with the gravity systems is surges. With battery systems, a surge is more tolerable. With a gravity system, there's no way to speed it up to take care of surges. It would just have to be in a big grid. The grid is a means of storage.

You have me say this before: You are forgetting about fast nuclear reactors to generate electricity. Note: FAST nuclear, not thermal that we are mostly using today. You wouldn't have to think about storage techniques, because it is not intermittant. Too many people discard nuclear because of the fear factor, but it has a better safety record than other methods, especially coal which has killed plenty of miners and generation facility workers. You say that uranium or thorium for fast nuclear needs to be mined? Eliminate that, because enough has already been mined to last centuries. We would already have (probably) several generations of demonstration plants if not for politics starting in 1994.

That sounds good. Would the waste be as dangerous as the current spent rods?

It could be used to convert seawater to fresh water. The Israelis and others are already doing it. If their costs figures reflect the actual costs, it's cheaper than what I'm paying for city water.

If we don't get safe, economical nuclear power, then my idea of a world wide grid of solar panels will come to past. As Jimmie Buffet would sing, "There's gotta be sunshine somewhere.

That sounds good. Would the waste be as dangerous as the current spent rods? No. Mostly because the highly radioactive portions of the used fuel (thermal reactor waste) are consumed generating power; this is one of the reasons fast nuclear makes more efficient use of the energy in uranium, thorium, plutonium, etc. Said another way: Fast nuclear consumes the highly radioactive and long half life transuranic actinides; that is, they are no longer present in the waste, and the process is about 100 times more efficient than thermal nuclear. Also, the waste is highly radioactive for much less time, because the highly radioactive portion has been consumed.

If we don't get safe, economical nuclear power, then my idea of a world wide grid of solar panels will come to past (sic.) Besides intermittancy, one of the problems with solar (and wind) is that they consume lots of real estate; I dont think we have enough land for those to be viable. Both will have problems with NIMBY--and so will nuclear due to the fear factor in so many people. Which fear is not warranted; see 2 books by Wade Allison.

Yes, it would take up a lot of land. However, they could be built over agriculture land without loss of production per German research.

https://cleantechnica.com/2017/11/24/combining-solar-panels-agriculture-makes-land-productive/

I saw that announcement about building over agricultural land. I'm waiting for peer reviews, and for farmers to comment before deciding. It seems improbable to me for plants that need sunlight and rain. Rain couldn't be evenly distributed as far as I know. Also what about the support structure for the solar panels? (I haven't read your referenced report yet.)

Just read the report. The research is in the very early stages of experimentation and continuing verification is needed. The report provided was from 2017; I have heard nothing else about it--has anyone?

One of their problems is arithmatic. The yield of any one plot was 80% of what it was with only one use.

The proposed support system didn't seem to take up much growing space, but could drastically affect the efficiency of planting and harvesting machinery.

We are setting up "Integrated Projects" by combining "Solar Power Projects" and "Agriculture Projects", to use land for both Food Production and Energy Production

Please have a look at

https://www.indiegogo.com/projects/replacing-fossil-fuels-by-solar-energy#/

We should definitely be investing in new nuclear. It is important to be realistic however. Nuclear is not good for using in peaking power plants, which is the niche that storage fills.

Peaking plants were around before the expansion of renewable energy and are needed even more now with the expansion of intermittent renewables. Solar and wind aren't going away anytime soon and neither are variations in demand.

Load shedding has much to recommend it. Load shed in consumers' premises has a lot to recommend it, signaled over the network it can allow some (heating, cooling and refrigeration) loads can be shed for some minutes. Some rotating loads can be short term shed too in industry or in the home. Appropriate payment would be needed.

In a few years almost all lighting will be LED which can be fed ,say, 24 V giving multiple benefits, battery backup, solar charging, and computing gear no-break supply.

Critical rotating loads will largely be inverter driven . With their DC link battery backup can be cheaply provided.

The consumer premises battery/ies will of course provide protection against failure of the distribution system so giving a further benefits. Electric vehicle battery discards will provide a source of usable cheap batteries with a little effort.

With these newer technologies cost-benefit may well shift as I suggest.

A further improvement will come with larger supply grids, there is a hope of ambient temperature superconductivity so continent-wide ( or even intercontinental) grids can be anticipated.

Good article.

Would like to see more articles on energy storage being as it's key to a clean energy future, so please continue to output this good stuff.