This startup wants to use the Earth as a massive battery
(www.technologyreview.com)
from Aatube@kbin.melroy.org to technology@beehaw.org on 09 Aug 17:44
https://kbin.melroy.org/m/technology@beehaw.org/t/1112554
from Aatube@kbin.melroy.org to technology@beehaw.org on 09 Aug 17:44
https://kbin.melroy.org/m/technology@beehaw.org/t/1112554
A recent test shows that Quidnet’s technology can store energy in pressurized water underground for months at a time.
threaded - newest
Paywall…
here you go
https://archive.ph/GUjLJ
The article doesn't discuss how they pressurize water. Conventional pumped storage uses gravity,the water isn't actually pressurized itself. Plus the whole liquid thing. But otherwise, neat!
Pump It Up
Ya, usually liquids are compressed with air for any useful stored use. Otherwise something must continually pump. Maybe they are putting a large bladder into the ground?
If I get it right, the ground itself is the impermeable “bladder”, as the water is pressed into rock. The rock maintains the pressure onto the water until it is being released.
I would think all the incidents with fracking have shown rock not to be as impermeable as one would expect or want. Doing this and not causing huge issues seems very hard to me. And also very situational, which is a big problem pumped hydro has.
Pumped hydro works really well and is just about as efficient as we can realistically do, but you need to have the right circumstances. Like a biggish elevation difference, a place to store enough water at the top and bottom for it to be worth while and a connection in between to pump through and take out the energy in the other direction. Plus close enough to a place that needs the power not to be killed by transport losses.
This thing seems to require the perfect conditions as well, which may prove even harder to find compared to places for pumped hydro.
I agree. It’s also a question of how many cycles the impermeability of the rock lasts.
Also incidents with water ending up in the wrong layers of rock can have dramatic consequences, as seen e.g. in Staufen in Germany. Wikipedia article (in German)
You and @Thorry84@feddit.nl really summed up my concerns and knowledge gaps succinctly! Don't want to frac, but don't want to miss an opportunity, either. Hard to beat pumped, tho. When applicable.
I wonder if this suffers from the same power density issue as most alternatives to pumped hydro systems. It's REALLY hard to do better than megatons of water pumped 500 meters up a hill.
yeah, the scalability of this seems like a pretty big challenge
annoyingly, they talk about the amount of water they pumped only in terms of energy (35MWh) and not in terms of water volume.
I think they do that because, if you estimate the water volume…it’s pretty unimpressive.
going off the numbers for Bath County Pumped Storage Station, the largest in the US, and until 2021 the largest in the world:
total storage capacity of 24,000 MWh - meaning that this power station built in the late 70s / early 80s has almost 700 times the storage capacity of this 35MWh demo
between their upper reservoir and lower reservoir, their water capacity is 78.4 million cubic meters. so as a crude estimate, Quidnet’s demo project used ~115,000 cubic meters.
Olympic swimming pool contains 2.500 cubic meters. so, again with the caveat that this is a rough estimate because Quidnet didn’t publish the actual numbers…this demo they’re bragging about involved 45 Olympic swimming pools worth of water.
Obviously, assuming you have that hill.
Slightly harder to do in places like the Netherlands for example, where the tallest hill is 322 metres, and the second tallest that isn’t part of that same mountain range near the Belgium border is just 110.
And in the US, Florida, Delaware, Louisiana, Mississippi, Indiana, and Illinois are actually flatter than the Netherlands - sure, the highest point in Indiana (Hoosier Hill) is 383 metres from the sea level, but the lowest point in the entire state is 98 metres above.
True! I just wonder how much energy they'd realistically be able to store for a given amount of resources. Like, does this have the same issues as Lifted Weight Storage? Where the energy density just doesn't really make sense once you get right down to it. I don't know the relevant math to determine how much water and at what pressures might be required to scale this up to the 500MWh/1GWh range. It might be perfectly fine.
EDIT: fuck man I'm not writing well today. edited to make me sound like less of a cretin
In the cycling world it’s kinda funny how people try to make a low climbing century (100 mile route) as a first go, and where I am I have a glut of choices for centuries with well under 1,000 meters of climbing. I just cleared out a bunch of my routes, and still have two century routes with under 600m of climbing.
Isn’t this basically just fracking without the oil?
yep, 100%
that’s even one of their main selling points:
this seems to fall into the bucket of “fossil fuel industry looking for ways to diversify and still make profits even as fossil fuel usage declines”
also notable is that fracking for oil is typically a one-time (or at least time-limited) thing. you do it to some rock formation, extract the oil or natural gas from it, and then move on to another formation.
what they’re pursuing here seems to be repeated fracking, pumping water in and back out over and over again. this article about Racoon Mountain in TN for example, mentions a daily pumping cycle - fill up the reservoir using excess nuclear power at night, then drain it during the day.
they’re claiming success based on pumping in water, sealing it up for 6 months, then pumping it back out again. that’s very different from pumping water in and out of this “impermeable” rock every 24 hours, for years or decades (Racoon Mountain was built in the 1970s)
This doesn’t make any sense. EGS is already a thing, and this doesn’t exactly sound cheaper. The benefit you get from EGS is constant output instead of going through all this trouble to recreate a battery.
I’ll also note there’s no confirmation that this is a closed loop, meaning this could draw a lot of water in a region beset by ongoing drought.
This is gonna upset a dude I know who has a gun for an arm.