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by DrBazza 700 days ago
Why can't anywhere that has significant elevation should just pumped storage of water during the day and use hydro on the way back down?
6 comments

I’m not an expert on this topic, but I think it comes down to cost and scalability. You have to construct a new project with custom specs for the exact site you’re on, and the permitting for a large environmental change is another drag. For large scale batteries, they all are a somewhat complex power electronic wrapper around mass produced battery cell cans or pouches that can be dropped anywhere. The cost declines of batteries are undeniable and are not stopping anytime soon.
Not to mentioned all the dirty cheap second hand batteries becoming available as electric cars are scrapped.

For grid storage second hand batteries might be fine. If taking them out of a scrapped car is feasible.

No grid operator going to mess with scrap batteries. Even for home player new cells are so cheap that it's not worth messing around with used ones (esp when considering liability and insurance). Might work in third world countries tho who have even more appetite for reliable power.
Grid battery deployment is faster than EV market penetration in the USA. This is not something that can siphon off a fraction of EV batteries. It is a huge market in its own right.
What would be considered ruined Leaf EV batteries that have significant range loss (20% to 50% degradation, for a car that went around 60 miles with a full battery) are being used to cover peak load right now in California and have been used to do so for years.

https://www.youtube.com/watch?v=JqlOlqK_ot8

2nd life use cases for cheap, mass produced batteries like this are more common than you think.

But that isn't a mainstream case. It's notable for being weird. The 1000x larger Moss Landing battery facility just uses new, off-the shelf BESS units from LG.
Because there are fewer places than expected where it really makes sense. Was discussed in an old video of Practical Engineering: https://youtu.be/66YRCjkxIcg?si=PXArfkXkbCODeSAF&t=290
Australian National University has identified 616,000 potential locations: https://re100.eng.anu.edu.au/global/
Interesting but it appears to only take account the topographic feasibility of the project.

The first location I looked at (link is not working :(), it relies on building two dams on rivers (which is something we tend to do less not more) and would flood some houses ...

And there is supposedly a price estimate, but it's just an A, B, C, D or E ranking could not find some costs to make comparison with battery storage for example.

Batteries installed on concrete slabs are easier and cheaper, there are only so many places pumped hydro is feasible.

https://news.ycombinator.com/item?id=40919052

Batteries can also be installed basically instantly, with storage being added incrementally. Unlike a years long project of constructing a hydro battery before it enters operation.
NZ recently scraped Lake Onslow seasonal hydro storage. My estimate it was about 100x cheaper per kWh when compared with Powerwall.
Can you provide background and/or context as to how and why this decision was made?
New government (that Elon Musk himself congratulated) has terminated tons of projects and rolled back some laws:

- Removed EV subsidy

- Scrapped Lake Onslow seasonal pumped hydro storage

- Removed generational smoking ban (made it to 18yo like most countries)

- Gave 50% discount to heated tobacco products (aka IQOS)

- Gave a tip whose projects will be fast tracked

- Reduced housing insulation minimums

- Terminated new inter-island ferry project to replace aging ferries (tbh this one was getting out of proportion)

- Reintroduced tax interest write-off for landlords who rent their houses

- Removed free school launches for poorest country schools

Their goal was to end government spending, but giving $2b+ to countries richest people seems opposite.

And to give them credit here's couple of good things that will definitely help property market:

- Ability to import abroad-certified building supplies (atm there's a building supply monomopoly)

- Ability to build up 60sqm backyard homes without consent

- Densification plans

Oof. Good luck over there.
There is zero chance that a mega-project like pumped hydro can be undertaken in the US in the current regulatory environment. NEPA review allows even clearly green projects like solar and wind to get bogged down in environmental review lawsuits. A project with major environmental impact like destroying an entire valley ecosystem to build a dam would be DoA.
It's not just nepa. Citizens really don't like pumped hydro which negatively impacts it's ability to be deployed (you need local permits as well as federal).

Bear lake Idaho has been talking about putting in pumped storage since the 2000s. On paper, it's pretty much the perfect geography for it. However, various concerns from the impact on local fishing to the impacts on the lakebed have ground that process to a halt. It's a 20+ year project that's gone nowhere.

That's why I'm largely negative on pumped hydro. On paper it seems nice, in practice it's almost impossible to get off the ground. Batteries, on the other hand, take almost no effort to install.

Yep, agreed. We probably need new chemistries to get the seasonal storage potential of pumped hydro. But I’m quite bullish on batteries in general, it seems while folks have been gnashing teeth on how expensive they are, a substantial proportion of renewables installs in the US include 4-6H of battery capacity, which at least substantially helps with the duck curve.
> We probably need new chemistries to get the seasonal storage potential of pumped hydro.

Yup. It might be possible to overbuild solar/wind to solve the problem (just need enough juice to offset the night). Won't be possible with current chemistries to have enough power to cover cloudy days or snow-covered solar panels.

> it seems while folks have been gnashing teeth on how expensive they are

This to me seems like a fixed perception based on outdated information. Batteries were quite expensive and required loads of rare earth/horrible chemicals to produce... 30 years ago when NiCd was fairly prominent. Now they are dirt cheap and due to get even cheaper with sodium ion coming to market. We are already manufacturing TWh of batteries yearly. Enough that we could theoretically have a full day backup everywhere in 10 to 20 years without any growth in manufacturing capacity.

good. because if you are storing kinetic, better to use a flywheel or something with less environmental impact
Do the math on how much energy you can store-- the volumes required for meaningful amounts of energy are just mind boggling. So you don't just need elevation, you need thousand of acres of valley or crater that you can flood and people tend to get a little testy about geoengineering at those scales these days.
Meh? Couple hundred meters of elevation and a hundred acres runs a city for day. Source - the city I live in which has this exact setup.
Indeed, but that is the scale you have to work at for it to be interesting... on the order of a billion gallons of water, if I assume it's 10m deep.