Pump it up
August 20, 2018 9:57 AM Subscribe
The trouble with solar power generator is that it's hard to store electricity. Batteries are expensive. Flywheels are cool but expensive and have undesirable failure modes. Near San Diego, water authority officials want to create a pumped hydro storage facility that could store up to 500 MW. But what if you don't already have a huge reservoir? A Swiss startup wants to use a crane to lift concrete blocks as a storage mechanism.
That probably couldn't be scaled-down to supplement off-grid residential solar, could it?
posted by Alvy Ampersand at 10:38 AM on August 20, 2018
posted by Alvy Ampersand at 10:38 AM on August 20, 2018
Upon reflection, kinetic batteries like this are nothing new. I wonder where else they have been used?
Some bored Swiss engineer, staring at the clock all day...
posted by GuyZero at 10:39 AM on August 20, 2018 [17 favorites]
Some bored Swiss engineer, staring at the clock all day...
posted by GuyZero at 10:39 AM on August 20, 2018 [17 favorites]
Over at HN they've been pondering the technical merits of the project and it seems like the problem would be the crane. Most construction-type cranes aren't suited to run 24/7, or they would need a lot of maintenance to operate that way.
I'm a little more keen on this idea from Eduard Heindl at Furtwangen University, which involves carving a massive cylinder into the landscape and raising it with stored hydraulic energy.
Heindl believes you could store 1.6 Terawatt-hours in under half a square mile. You could even live on top of it!
posted by JoeZydeco at 10:42 AM on August 20, 2018 [5 favorites]
I'm a little more keen on this idea from Eduard Heindl at Furtwangen University, which involves carving a massive cylinder into the landscape and raising it with stored hydraulic energy.
Heindl believes you could store 1.6 Terawatt-hours in under half a square mile. You could even live on top of it!
posted by JoeZydeco at 10:42 AM on August 20, 2018 [5 favorites]
Unfortunately most of the low-hanging fruit for pumped storage has already been utilized. Physics professor Tom Murphy blogged a while back about the challenges of gravitational storage models: https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ I seem to recall him even taking on the ARES rail-based gravity storage solution, but my google-fu is failing me on that one.
posted by St. Oops at 10:46 AM on August 20, 2018 [4 favorites]
posted by St. Oops at 10:46 AM on August 20, 2018 [4 favorites]
You could even live on top of it!
I don't see an estimate for the pressure the water would be under in that system. It seems like a lot. Like, way more than you could ever run water sealant and o-rings at. So much easier to use a lake/reservoir.
posted by GuyZero at 10:46 AM on August 20, 2018
I don't see an estimate for the pressure the water would be under in that system. It seems like a lot. Like, way more than you could ever run water sealant and o-rings at. So much easier to use a lake/reservoir.
posted by GuyZero at 10:46 AM on August 20, 2018
FWIW, battery storage is now a viable solution at the residential level. This time last year my company didn't even offer it—not cost-competitive, too much maintenance, etc.—but now we have two different products and several installations under our belts. All of a sudden, we're there.
It's pretty cool and has interesting implications for the grid itself. PV is a very exciting industry to be in, right now.
posted by Anticipation Of A New Lover's Arrival, The at 10:47 AM on August 20, 2018 [10 favorites]
It's pretty cool and has interesting implications for the grid itself. PV is a very exciting industry to be in, right now.
posted by Anticipation Of A New Lover's Arrival, The at 10:47 AM on August 20, 2018 [10 favorites]
I don't see an estimate for the pressure the water would be under in that system.
Slide 17. Seems like the pressure would run from 25 bar (~360 psi) on the small end to 200 bar (2900 psi) on the 1600 GWh model. And, yeah, a failure on this would be pretty spectacular. But I believe 3000+ psi seals are a solved engineering problem. Perhaps not on a kilometer-wide basis, though...
posted by JoeZydeco at 10:55 AM on August 20, 2018 [1 favorite]
Slide 17. Seems like the pressure would run from 25 bar (~360 psi) on the small end to 200 bar (2900 psi) on the 1600 GWh model. And, yeah, a failure on this would be pretty spectacular. But I believe 3000+ psi seals are a solved engineering problem. Perhaps not on a kilometer-wide basis, though...
posted by JoeZydeco at 10:55 AM on August 20, 2018 [1 favorite]
Here's a Vox article from 2016 about a horizontal version of this idea: instead of building a tower of concrete blocks, you have essentially a trainyard full of tracks and electric motor-powered rolling stock carrying concrete blocks over a gentle incline. They claim an 86% efficiency which is basically the same as the 85% efficiency quoted for the crane system.
posted by mhum at 10:57 AM on August 20, 2018 [7 favorites]
posted by mhum at 10:57 AM on August 20, 2018 [7 favorites]
I love how our methods for storing and generating electricity are still so "primitive." I dig the idea of storing energy in these blocks, I hope this tech gets some backing because our reliance on lithium seems very shorted sighted, isn't that one of the materials that are rare here, plus require devastating the land to even mine?
posted by GoblinHoney at 11:00 AM on August 20, 2018
posted by GoblinHoney at 11:00 AM on August 20, 2018
The failure modes of anything mechanical that has megajoules of potential energy stored are going to be pretty spectacular.
I'm still of the opinion that hydrogen or some hydrocarbon synthesis is the best idea. If the efficiency and production poisoning problems can be solved, then that to me seems ideal: a transportable, fungible fuel that we already understand and can be used in infrastructure we largely already have, like static turbine generators. And storage isn't anywhere nearly as bulky.
posted by bonehead at 11:02 AM on August 20, 2018 [3 favorites]
I'm still of the opinion that hydrogen or some hydrocarbon synthesis is the best idea. If the efficiency and production poisoning problems can be solved, then that to me seems ideal: a transportable, fungible fuel that we already understand and can be used in infrastructure we largely already have, like static turbine generators. And storage isn't anywhere nearly as bulky.
posted by bonehead at 11:02 AM on August 20, 2018 [3 favorites]
That probably couldn't be scaled-down to supplement off-grid residential solar, could it?
Well, let's compare it to a PowerWall, which is supposed to store 13.5kWh of energy. That's 13.5*1000*60*60 = 48 million Joules of energy. Let's say you can lift some stuff 15 feet in the air; call it 5 meters for easy rounding. And we'll round gravity to 10 meters per second squared. You have to lift 48600000 / (5*10) = 972000 kilograms of stuff. Shit, that is a LOT of stuff. Did I math something wrong? Because it seems like it would be really hard to be competitive with a PowerWall by lifting stuff.
posted by a snickering nuthatch at 11:03 AM on August 20, 2018 [5 favorites]
Well, let's compare it to a PowerWall, which is supposed to store 13.5kWh of energy. That's 13.5*1000*60*60 = 48 million Joules of energy. Let's say you can lift some stuff 15 feet in the air; call it 5 meters for easy rounding. And we'll round gravity to 10 meters per second squared. You have to lift 48600000 / (5*10) = 972000 kilograms of stuff. Shit, that is a LOT of stuff. Did I math something wrong? Because it seems like it would be really hard to be competitive with a PowerWall by lifting stuff.
posted by a snickering nuthatch at 11:03 AM on August 20, 2018 [5 favorites]
I don't see an estimate for the pressure the water would be under in that system.
On page 17 of the Heindl presentation is a table listing several parameters for various sizes of cylinder. The smallest listed can store 0.5GWh with a pressure of 25 bar. Which is about three times the pressure of a domestic water supply, so, high, but nothing heavy-duty kit can't deal with.
posted by Stoneshop at 11:08 AM on August 20, 2018
On page 17 of the Heindl presentation is a table listing several parameters for various sizes of cylinder. The smallest listed can store 0.5GWh with a pressure of 25 bar. Which is about three times the pressure of a domestic water supply, so, high, but nothing heavy-duty kit can't deal with.
posted by Stoneshop at 11:08 AM on August 20, 2018
You have to lift 48600000 / (5*10) = 972000 kilograms of stuff.
About 28 of the cylinders they propose. Except they lift them a lot higher and I'm too lazy to see if the power storage goes up linearly or with the square of the lift height. Even so they lift things a lot higher so probably need half or a quarter of that many lifts, so say 7. Not that many really.
posted by GuyZero at 11:08 AM on August 20, 2018 [2 favorites]
About 28 of the cylinders they propose. Except they lift them a lot higher and I'm too lazy to see if the power storage goes up linearly or with the square of the lift height. Even so they lift things a lot higher so probably need half or a quarter of that many lifts, so say 7. Not that many really.
posted by GuyZero at 11:08 AM on August 20, 2018 [2 favorites]
Some weird stuff with this that I’d want to see breakdowns on.
1) Concrete is generally more dense than water, yes, because it’s rocks and cement. Plus most modern concrete is reinforced with steel. Concrete is typically used because it’s strong in compression relative to its weight and we’ve gotten pretty good at making it. Is there a cheaper more-dense material that makes more sense?
2) Issues with varying specific gravities, especially if you’re trying to use waste materials.
3) Concrete is messy and energy-intensive to make. Making 35 ton blocks is not something your random concrete contractor is going to be good at.
4) This might be a good way to jump-start PV systems in post-disaster areas. I was working on a Cascadia project this year and “how do we actually get the energy needed to start the system” was a significant design challenge given our design and operation requirements. “Drop a heavy thing a good distance” is def worth considering in some situations.
posted by curious nu at 11:09 AM on August 20, 2018 [2 favorites]
1) Concrete is generally more dense than water, yes, because it’s rocks and cement. Plus most modern concrete is reinforced with steel. Concrete is typically used because it’s strong in compression relative to its weight and we’ve gotten pretty good at making it. Is there a cheaper more-dense material that makes more sense?
2) Issues with varying specific gravities, especially if you’re trying to use waste materials.
3) Concrete is messy and energy-intensive to make. Making 35 ton blocks is not something your random concrete contractor is going to be good at.
4) This might be a good way to jump-start PV systems in post-disaster areas. I was working on a Cascadia project this year and “how do we actually get the energy needed to start the system” was a significant design challenge given our design and operation requirements. “Drop a heavy thing a good distance” is def worth considering in some situations.
posted by curious nu at 11:09 AM on August 20, 2018 [2 favorites]
The conceptual drawing seems like a fragile system in earthquake-land. I guess cylindrical blocks remove an axis of alignment from the worries of stacking, but square or rectangular blocks would give you the ability to have staggered stacks (like bricks) which I would think might be more robust if the ground starts moving (or the airstrikes are called).
posted by maxwelton at 11:14 AM on August 20, 2018 [3 favorites]
posted by maxwelton at 11:14 AM on August 20, 2018 [3 favorites]
While this tower method might have some limited applications, it is surprisingly expensive by numbers they provide. It isn't much cheaper than lithium batteries which are much more compact and getting cheaper. It requires 40 story tall towers so locations are limited.
This might be a short term solution, but I think improving battery technology is the long run solution.
posted by JackFlash at 11:20 AM on August 20, 2018 [3 favorites]
This might be a short term solution, but I think improving battery technology is the long run solution.
posted by JackFlash at 11:20 AM on August 20, 2018 [3 favorites]
About 28 of the cylinders they propose. Except they lift them a lot higher and I'm too lazy to see if the power storage goes up linearly or with the square of the lift height. Even so they lift things a lot higher so probably need half or a quarter of that many lifts, so say 7. Not that many really.
I interpreted the comment I was replying to (perhaps incorrectly) as about scaling gravitational potential energy storage for individual residential use. (Energy stored is linear with height).
posted by a snickering nuthatch at 11:20 AM on August 20, 2018
I interpreted the comment I was replying to (perhaps incorrectly) as about scaling gravitational potential energy storage for individual residential use. (Energy stored is linear with height).
posted by a snickering nuthatch at 11:20 AM on August 20, 2018
I did some quick calculations of the energy density of the tower system vs lithium batteries. The tower system has an energy density of less than 0.4 watt-hours per kilogram (assuming maximum 120 meter height, most blocks are lower). Lithium batteries hold around 400 watt-hours per kilogram, about 1000 times the energy density. You need a literal ton of concrete to equal a kilogram of lithium battery.
That's why the tower system is so expensive. You need one hell of a lot of gravel and concrete to get anything approaching battery storage.
posted by JackFlash at 11:28 AM on August 20, 2018 [4 favorites]
That's why the tower system is so expensive. You need one hell of a lot of gravel and concrete to get anything approaching battery storage.
posted by JackFlash at 11:28 AM on August 20, 2018 [4 favorites]
mhum: "Here's a Vox article from 2016 about a horizontal version of this idea: instead of building a tower of concrete blocks, you have essentially a trainyard full of tracks and electric motor-powered rolling stock carrying concrete blocks over a gentle incline. "
Was coming to post this. This method is buck simple using proven technology but requires a lot of area. It's also fairly easy to control and you'd really have to work at getting the sort of massive energy release that bonehead mentioned.
curious nu: " Concrete is generally more dense than water, yes, because it’s rocks and cement. Plus most modern concrete is reinforced with steel. Concrete is typically used because it’s strong in compression relative to its weight and we’ve gotten pretty good at making it. Is there a cheaper more-dense material that makes more sense?"
Concrete's big advantage is it is cheap and moldable mass. And because you need a lot of mass it's probably always going to be used. Things like lead are much denser but way more expensive. And really volume is rarely that much of a constraint on these projects.
curious nu: " Concrete is messy and energy-intensive to make. Making 35 ton blocks is not something your random concrete contractor is going to be good at."
Anyone running a batch plant could make blocks. And the blocks don't have to monolithic. Those massive legoest retaining blocks are a good example of what could be done.
posted by Mitheral at 11:33 AM on August 20, 2018 [3 favorites]
Was coming to post this. This method is buck simple using proven technology but requires a lot of area. It's also fairly easy to control and you'd really have to work at getting the sort of massive energy release that bonehead mentioned.
curious nu: " Concrete is generally more dense than water, yes, because it’s rocks and cement. Plus most modern concrete is reinforced with steel. Concrete is typically used because it’s strong in compression relative to its weight and we’ve gotten pretty good at making it. Is there a cheaper more-dense material that makes more sense?"
Concrete's big advantage is it is cheap and moldable mass. And because you need a lot of mass it's probably always going to be used. Things like lead are much denser but way more expensive. And really volume is rarely that much of a constraint on these projects.
curious nu: " Concrete is messy and energy-intensive to make. Making 35 ton blocks is not something your random concrete contractor is going to be good at."
Anyone running a batch plant could make blocks. And the blocks don't have to monolithic. Those massive legoest retaining blocks are a good example of what could be done.
posted by Mitheral at 11:33 AM on August 20, 2018 [3 favorites]
Unfortunately most of the low-hanging fruit for pumped storage has already been utilized.
Elementary physics will tell you that low-hanging fruit provides very little potential energy. It's the high-hanging fruit you need to go after.
posted by Stoneshop at 11:34 AM on August 20, 2018 [36 favorites]
Elementary physics will tell you that low-hanging fruit provides very little potential energy. It's the high-hanging fruit you need to go after.
posted by Stoneshop at 11:34 AM on August 20, 2018 [36 favorites]
Unfortunately most of the low-hanging fruit for pumped storage has already been utilized.
What they meant was that the easiest pumped storage sites have all been developed. Successively harder to develop sites will return less on their investment (EROEI).
posted by M-x shell at 11:41 AM on August 20, 2018
Elementary physics will tell you that low-hanging fruit provides very little potential energy. It's the high-hanging fruit you need to go after.
What they meant was that the easiest pumped storage sites have all been developed. Successively harder to develop sites will return less on their investment (EROEI).
posted by M-x shell at 11:41 AM on August 20, 2018
Can we develop tiny wind turbines to capture the energy of jokes whooshing over heads?
posted by borkencode at 11:48 AM on August 20, 2018 [35 favorites]
posted by borkencode at 11:48 AM on August 20, 2018 [35 favorites]
I love how popular this story has been online. I think because the core idea is so simple and appealing. "Just stack blocks!" It's an invitation to pencil-and-napkin math and related ideas.
If you're ever in the right part of middle-of-nowhere Scotland, definitely recommend a visit to the Cruachan Power Station. It's a remarkable hydroelectric based power storage system and they do a nice tour. The lake up high and the lake down below existed already, the crazy thing is they dug a giant cave into the mountain to house the turbines without spoiling the Highland beauty. Building it cost 36 lives. Here's a fun Pathé short from when the Queen opened the plant.
posted by Nelson at 11:48 AM on August 20, 2018 [2 favorites]
If you're ever in the right part of middle-of-nowhere Scotland, definitely recommend a visit to the Cruachan Power Station. It's a remarkable hydroelectric based power storage system and they do a nice tour. The lake up high and the lake down below existed already, the crazy thing is they dug a giant cave into the mountain to house the turbines without spoiling the Highland beauty. Building it cost 36 lives. Here's a fun Pathé short from when the Queen opened the plant.
posted by Nelson at 11:48 AM on August 20, 2018 [2 favorites]
Ugh: who let the energy VCs into coke stash again? The energy density is dismal, the energy embodied in the weights ridiculous (know how much CO₂ is involved in making concrete?), the efficiency mince, the amount of maintenance stupid … this is energy clickbait up there with the SOLAR ROADS!!!1! shite from a few years back. Built to prey on energy system illiterates. No no no.
posted by scruss at 12:02 PM on August 20, 2018 [10 favorites]
posted by scruss at 12:02 PM on August 20, 2018 [10 favorites]
Another easy-to-digest infographic on the concept of gravity batteries.
posted by eclectist at 12:15 PM on August 20, 2018 [1 favorite]
posted by eclectist at 12:15 PM on August 20, 2018 [1 favorite]
The failure modes of anything mechanical that has megajoules of potential energy stored are going to be pretty spectacular.
Hee, definitely. But unless I missed something major hydrogen or some hydrocarbon synthesis are themselves full of dangers that haven't entirely been solved; hydrogen is still a pretty unstable fuel, all the recent cool stuff with ULEMCO notwithstanding. Hydrocarbon synthesis tends to have some pretty nasty byproducts, although it's still probably a cleaner use of oil than what we're currently doing with it.
A huge part of the appeal for mechanical storage is how inherently less toxic most of it is compared to the alternatives.
I really hope someone's working on those weird spring batteries in The Wind Up Girl.
posted by aspersioncast at 12:17 PM on August 20, 2018 [3 favorites]
Hee, definitely. But unless I missed something major hydrogen or some hydrocarbon synthesis are themselves full of dangers that haven't entirely been solved; hydrogen is still a pretty unstable fuel, all the recent cool stuff with ULEMCO notwithstanding. Hydrocarbon synthesis tends to have some pretty nasty byproducts, although it's still probably a cleaner use of oil than what we're currently doing with it.
A huge part of the appeal for mechanical storage is how inherently less toxic most of it is compared to the alternatives.
I really hope someone's working on those weird spring batteries in The Wind Up Girl.
posted by aspersioncast at 12:17 PM on August 20, 2018 [3 favorites]
Oh, and speaking of large-scale energy storage, there was also this NYT article from a month ago about some (seemingly) serious proposals to turn the Hoover Dam (!!) into a pumped-storage hydro thing.
posted by mhum at 12:19 PM on August 20, 2018
posted by mhum at 12:19 PM on August 20, 2018
FWIW, battery storage is now a viable solution at the residential level.
They're starting to undercut NG peakers too. I don't know whether Li-Ion is going to be the One True Battery for every application, but it's starting to look tough to beat that laptops->cars->grid learning curve.
posted by rhamphorhynchus at 12:48 PM on August 20, 2018 [1 favorite]
They're starting to undercut NG peakers too. I don't know whether Li-Ion is going to be the One True Battery for every application, but it's starting to look tough to beat that laptops->cars->grid learning curve.
posted by rhamphorhynchus at 12:48 PM on August 20, 2018 [1 favorite]
Here's a different kind of energy tower. One of the remaining German WW2 flak towers converted to produce enough electricity and heat to meet some local demand.
posted by biffa at 12:48 PM on August 20, 2018
posted by biffa at 12:48 PM on August 20, 2018
Lots of good points in the discussion. I'll add that any energy storage solution is going to be dangerous in proportion to the amount of energy it stores. Hydro: A dam break will destroy millions of acres. Battery: A battery fire at a megajoule facility will be a scene of spectacular destruction. Piling up blocks: Watch a million tons of blocks fall down in an earthquake. An underground hydraulic thing: Let's see what happens if it develops a leak. Gasoline, hydrogen, propane, rocket fuel... the value of all of it is that it stores a lot of energy, and the danger of all of it is that it stores a lot of energy.
posted by clawsoon at 1:10 PM on August 20, 2018 [4 favorites]
posted by clawsoon at 1:10 PM on August 20, 2018 [4 favorites]
The failure modes of undersea pumped hydro are pretty benign AFAIK. Unfortunately maintaining anything undersea is always harder than it seems at first glance.
The 'hydraulically raise a cylinder of rock' concept is something only a physicist could love. How perfectly round is that 1 kilometer diameter metal casing really going to be, nevermind after a year? And those O-rings are supposed to hold 10 bar? Really.
posted by anthill at 1:27 PM on August 20, 2018 [2 favorites]
The 'hydraulically raise a cylinder of rock' concept is something only a physicist could love. How perfectly round is that 1 kilometer diameter metal casing really going to be, nevermind after a year? And those O-rings are supposed to hold 10 bar? Really.
posted by anthill at 1:27 PM on August 20, 2018 [2 favorites]
Hydro: A dam break will destroy millions of acres.
Dam breaks can be pretty bad but because they're usually next to a river that can take all the water away it's not like a flood caused by heavy rain. e.g. The Oroville dam failure. On the other hand if you had the poor fortune to build a city along the river downstream from the damn, yeah, that's bad.
For some reason FEMA maintains a while web site about dam failures.
posted by GuyZero at 1:28 PM on August 20, 2018
Dam breaks can be pretty bad but because they're usually next to a river that can take all the water away it's not like a flood caused by heavy rain. e.g. The Oroville dam failure. On the other hand if you had the poor fortune to build a city along the river downstream from the damn, yeah, that's bad.
For some reason FEMA maintains a while web site about dam failures.
posted by GuyZero at 1:28 PM on August 20, 2018
In terms of risk management, hydro and liquid fuels are quite well understood and there are sophisticated engineering and environmental controls for all those modes, including a large pool of experienced labour to do it. Gaseous fuel and batteries are somewhat less well developed, but still safe.
As someone mentioned upthread, I'd be concerned about earthquakes with the block stackers. I seen proposals for gravel lifts which frankly seem slightly less crazypants, but even so. Moving parts are insanity. Hundreds of them even more so.
I'm more optimistic about gravel thermal storage, as they make some thermodynamic sense and again don't rely entirely on hundreds of moving parts. They're just big heat pumps, which, again , are reasonably mature technologies.
posted by bonehead at 1:29 PM on August 20, 2018 [1 favorite]
As someone mentioned upthread, I'd be concerned about earthquakes with the block stackers. I seen proposals for gravel lifts which frankly seem slightly less crazypants, but even so. Moving parts are insanity. Hundreds of them even more so.
I'm more optimistic about gravel thermal storage, as they make some thermodynamic sense and again don't rely entirely on hundreds of moving parts. They're just big heat pumps, which, again , are reasonably mature technologies.
posted by bonehead at 1:29 PM on August 20, 2018 [1 favorite]
The 'hydraulically raise a cylinder of rock' concept is something only a physicist could love. How perfectly round is that 1 kilometer diameter metal casing really going to be
Assume a spherical cow ...
posted by JackFlash at 1:33 PM on August 20, 2018 [3 favorites]
Assume a spherical cow ...
posted by JackFlash at 1:33 PM on August 20, 2018 [3 favorites]
In a pressure cylinder, the stress on the walls rises with the square of the radius. So if you want to hold the same pressure in a 1km cylinder that you hold in a 1m cylinder, you need walls which are a million times thicker.
posted by clawsoon at 1:45 PM on August 20, 2018
posted by clawsoon at 1:45 PM on August 20, 2018
"This might be a short term solution, but I think improving battery technology is the long run solution."
Aren't there very real limits to how good our batteries can be, what resources are available to drain from the earth to make them, and how toxic it is to get at them? Plus once disasters start hitting, seems like people will be able to get the principles of liftign a big heavy thing more than whatever alchemy is involved in making modern batteries.
posted by GoblinHoney at 2:08 PM on August 20, 2018
Aren't there very real limits to how good our batteries can be, what resources are available to drain from the earth to make them, and how toxic it is to get at them? Plus once disasters start hitting, seems like people will be able to get the principles of liftign a big heavy thing more than whatever alchemy is involved in making modern batteries.
posted by GoblinHoney at 2:08 PM on August 20, 2018
I'll add that any energy storage solution is going to be dangerous in proportion to the amount of energy it stores.
What about thermal energy storage with ice? That seems pretty easy to contain.
posted by JoeZydeco at 2:10 PM on August 20, 2018 [1 favorite]
What about thermal energy storage with ice? That seems pretty easy to contain.
posted by JoeZydeco at 2:10 PM on August 20, 2018 [1 favorite]
Aren't there very real limits to how good our batteries can be, what resources are available to drain from the earth to make them, and how toxic it is to get at them?
Lithium is one of the most plentiful elements on the earth. It isn't very toxic. In fact it is used in medicines in small doses. It is relatively clean to mine compared to just about anything else. The biggest source in Chile is from evaporation of salt ponds. So mining it is similar to producing table salt. It could even be mined from sea water relatively cheaply.
There are very minor constituents of lithium batteries that are more of a problem, for example cobalt. But there are lithium batteries now that are mostly eliminating it.
posted by JackFlash at 2:19 PM on August 20, 2018 [2 favorites]
Lithium is one of the most plentiful elements on the earth. It isn't very toxic. In fact it is used in medicines in small doses. It is relatively clean to mine compared to just about anything else. The biggest source in Chile is from evaporation of salt ponds. So mining it is similar to producing table salt. It could even be mined from sea water relatively cheaply.
There are very minor constituents of lithium batteries that are more of a problem, for example cobalt. But there are lithium batteries now that are mostly eliminating it.
posted by JackFlash at 2:19 PM on August 20, 2018 [2 favorites]
Aren't there very real limits to how good our batteries can be, what resources are available to drain from the earth to make them, and how toxic it is to get at them?
But necessarily. Flow batteries are growing in popularity and use a variety of generally cheaper and less toxic materials.
posted by smoke at 2:22 PM on August 20, 2018 [1 favorite]
But necessarily. Flow batteries are growing in popularity and use a variety of generally cheaper and less toxic materials.
posted by smoke at 2:22 PM on August 20, 2018 [1 favorite]
Y'all might be interested in my project, iRth.
Using waste material which was destined to be thrown out, I made a sphere1 which has an insulating outer layer and a molten iron core. One cool thing: the energy used to build it was captured in this core (at an efficiency estimated to be in the high 90th percentile), and so didn't even need to be "charged" to start working.
But the coolest thing? You can live on the insulating layer, as users of the prototype are demonstrating today.
All in all, the prototype works well. When we move from the current alpha (0.7.4.2) to beta (0.8.x) we'll be addressing some of the minor concerns which have been raised by early adopters. Though we haven't been able to replicate this on our dev unit, apparently the insulating layer can crack and allow trace amounts of the molten storage medium to leak to the surface. It's important to emphasize that the insulator is self-healing--such leakage, if it can be shown to exist, would only cause minor, localized damage.
Please subscribe to my Patreon if you want my team and I to continue development. Subscribers get a range of goodies, but iRth is for everyone, subscriber or not.
1 Due to an error when it was machined--since corrected in CAM--the prototype is an "oblate spheroid".
[Edited to add: I just took a look at the analytics for how the prototype iRthers are utilizing the storage medium. WTF? You're literally standing on endless energy. My team and I are now considering a ground-up rewrite to improve the user interface.]
posted by maxwelton at 2:33 PM on August 20, 2018 [17 favorites]
Using waste material which was destined to be thrown out, I made a sphere1 which has an insulating outer layer and a molten iron core. One cool thing: the energy used to build it was captured in this core (at an efficiency estimated to be in the high 90th percentile), and so didn't even need to be "charged" to start working.
But the coolest thing? You can live on the insulating layer, as users of the prototype are demonstrating today.
All in all, the prototype works well. When we move from the current alpha (0.7.4.2) to beta (0.8.x) we'll be addressing some of the minor concerns which have been raised by early adopters. Though we haven't been able to replicate this on our dev unit, apparently the insulating layer can crack and allow trace amounts of the molten storage medium to leak to the surface. It's important to emphasize that the insulator is self-healing--such leakage, if it can be shown to exist, would only cause minor, localized damage.
Please subscribe to my Patreon if you want my team and I to continue development. Subscribers get a range of goodies, but iRth is for everyone, subscriber or not.
1 Due to an error when it was machined--since corrected in CAM--the prototype is an "oblate spheroid".
[Edited to add: I just took a look at the analytics for how the prototype iRthers are utilizing the storage medium. WTF? You're literally standing on endless energy. My team and I are now considering a ground-up rewrite to improve the user interface.]
posted by maxwelton at 2:33 PM on August 20, 2018 [17 favorites]
The energy density is dismal
You may remember the concept from the heady days of peak Peak Oil, when everyone was chatting about energy. Every other week or so, someone would come up with a variation on this idea, only to be met with a flurry of calculations showing that calling it a "viable alternative to pumped-hydro" is sort of like calling your rusty tricycle a viable alternative to an iron ore hauler.
posted by sfenders at 2:53 PM on August 20, 2018 [1 favorite]
You may remember the concept from the heady days of peak Peak Oil, when everyone was chatting about energy. Every other week or so, someone would come up with a variation on this idea, only to be met with a flurry of calculations showing that calling it a "viable alternative to pumped-hydro" is sort of like calling your rusty tricycle a viable alternative to an iron ore hauler.
posted by sfenders at 2:53 PM on August 20, 2018 [1 favorite]
Y'all might be interested in my project, iRth.
Empirically the molten part is too far to be useful in most places and the availability of hot delicious magma is strongly correlated with earthquakes.
So: yes, but.
posted by GuyZero at 2:57 PM on August 20, 2018
Empirically the molten part is too far to be useful in most places and the availability of hot delicious magma is strongly correlated with earthquakes.
So: yes, but.
posted by GuyZero at 2:57 PM on August 20, 2018
I'll add that any energy storage solution is going to be dangerous in proportion to the amount of energy it stores.
Matter is a damn fine and very stable energy store.
Sadly, the universe still hasn't found a civilization grown-up enough to deserve it.
posted by Twang at 7:00 PM on August 20, 2018
Matter is a damn fine and very stable energy store.
Sadly, the universe still hasn't found a civilization grown-up enough to deserve it.
posted by Twang at 7:00 PM on August 20, 2018
A battery fire at a megajoule facility will be a scene of spectacular destruction.
Not really. Battery-based energy storage systems are modular, with each "bank" of batteries enclosed in a shipping container with its own fire detection and suppression system. Most fires would be confined to a single 2' x 2' x 6' battery stack within one container.
posted by rocket88 at 7:12 PM on August 20, 2018
Not really. Battery-based energy storage systems are modular, with each "bank" of batteries enclosed in a shipping container with its own fire detection and suppression system. Most fires would be confined to a single 2' x 2' x 6' battery stack within one container.
posted by rocket88 at 7:12 PM on August 20, 2018
Using gravitational potential energy to store power is feasible because it is cheap, in the case where you can leverage geography and pump water uphill. Proposals that do a capital intensive version are throwing away its main benefit. It doesn't rule it out since battery options are so poor but there's a lot of other ideas that might work too.
I was pleasantly surprised that the Quartz piece took the time to put it in perspective as a possible niche solution, rather than the disruptive innovation that will power the grid.
When the idea is live on a massive cylinder that goes up and down I don't know if I'm supposed to think of it as an SF setting (cool!) or a real proposal.
Ugh: who let the energy VCs into coke stash again? The energy density is dismal, the energy embodied in the weights ridiculous (know how much CO₂ is involved in making concrete?),
Energy density doesn't matter nearly as much for grid storage. This wouldn't work for laptop batteries or electric cars, obviously. And they aren't proposing using concrete.
posted by mark k at 7:23 PM on August 20, 2018
I was pleasantly surprised that the Quartz piece took the time to put it in perspective as a possible niche solution, rather than the disruptive innovation that will power the grid.
When the idea is live on a massive cylinder that goes up and down I don't know if I'm supposed to think of it as an SF setting (cool!) or a real proposal.
Ugh: who let the energy VCs into coke stash again? The energy density is dismal, the energy embodied in the weights ridiculous (know how much CO₂ is involved in making concrete?),
Energy density doesn't matter nearly as much for grid storage. This wouldn't work for laptop batteries or electric cars, obviously. And they aren't proposing using concrete.
posted by mark k at 7:23 PM on August 20, 2018
I'm beginning to come round to the idea that large scale grid storage isn't the best approach to using excess energy production from solar etc. Rather that power should be used for useful energy intensive operations that aren't directly time dependent. Examples would include boosting carbon capture systems (short term until those plants are shut down) hydrolysis, desalination and electrolysis of lithium salts. This would of course also require overbuilding non carbon energy systems to ensure capacity to meet high time specific demand and efforts to lower demand also such as greater consumer efficiency standards generally. That capacity can then be used as above when otherwise not needed.
Lithium batteries for local energy time shifting at the house or neighbourhood level are plenty practical though, as long as we can continue to increase lithium production without too much ecological destruction.
Pumped storage et al is great where practical, but scaling up has major engineering and safety challenges.
posted by Absolutely No You-Know-What at 8:45 PM on August 20, 2018 [2 favorites]
Lithium batteries for local energy time shifting at the house or neighbourhood level are plenty practical though, as long as we can continue to increase lithium production without too much ecological destruction.
Pumped storage et al is great where practical, but scaling up has major engineering and safety challenges.
posted by Absolutely No You-Know-What at 8:45 PM on August 20, 2018 [2 favorites]
So just like pulling on the chain of GIGANTIC MECHANICAL COO COO CLOCK?!?
Definitely needs the whatcouldpossiblygowrong tag.
posted by sammyo at 9:50 PM on August 20, 2018
Definitely needs the whatcouldpossiblygowrong tag.
posted by sammyo at 9:50 PM on August 20, 2018
If you're ever in the right part of middle-of-nowhere Scotland, definitely recommend a visit to the Cruachan Power Station.
There's another one in Wales, the Dinorwig Pumped Storage Power Station. With a nice writeup here.
posted by Stoneshop at 10:32 PM on August 20, 2018
There's another one in Wales, the Dinorwig Pumped Storage Power Station. With a nice writeup here.
posted by Stoneshop at 10:32 PM on August 20, 2018
There's a lot to be gained (as the article says) by investing in lots and lots of smaller solutions.
I think people need to think more about moving the kind of energy they want around rather than always thinking in terms of electricity.
For example, London is too hot. It's too hot because it's built on thick clay with train tunnels in and those train tunnels have been putting out heat for 100 years.
So you could spend electricity to try and cool them and also spent electricity somewhere else to heat your home, or you could take that heat and move it into homes.
The London Clay is basically a giant thermal battery already.
In Canada a whole town, The Drake Landing Solar Community, has taken to storing excess summer heat to keep themselves warm in winter.
On a smaller scale, maybe you could just bury a milk tanker in your back garden.
You could install PCM boards in homes. These are construction boards with microencapsulated wax beads ins, so that over a certain temperature (25c ish) they melt absorbing heat, and under a lower temperature (16C ish) they freeze releasing stored heat.
You could even build Phase Change batteries (basically boxes full of wax) fill them full of heat from server farms or whatever and then ship them off to places where you need that heat. (Ok, not hugely efficient, but people do and it's a different way of thinking about energy.
Or I guess you could just move the server farms making the heat to where you want the heat in the first place.
If every building had a solar installation and a little battery then you're not powering everyone from one big facility, you're just doing top up work.
Basically, thinking about energy purely in terms of producing and consuming electricity from the grid is very shortsighted. We can do better.
posted by Just this guy, y'know at 1:48 AM on August 21, 2018 [7 favorites]
I think people need to think more about moving the kind of energy they want around rather than always thinking in terms of electricity.
For example, London is too hot. It's too hot because it's built on thick clay with train tunnels in and those train tunnels have been putting out heat for 100 years.
So you could spend electricity to try and cool them and also spent electricity somewhere else to heat your home, or you could take that heat and move it into homes.
The London Clay is basically a giant thermal battery already.
In Canada a whole town, The Drake Landing Solar Community, has taken to storing excess summer heat to keep themselves warm in winter.
On a smaller scale, maybe you could just bury a milk tanker in your back garden.
You could install PCM boards in homes. These are construction boards with microencapsulated wax beads ins, so that over a certain temperature (25c ish) they melt absorbing heat, and under a lower temperature (16C ish) they freeze releasing stored heat.
You could even build Phase Change batteries (basically boxes full of wax) fill them full of heat from server farms or whatever and then ship them off to places where you need that heat. (Ok, not hugely efficient, but people do and it's a different way of thinking about energy.
Or I guess you could just move the server farms making the heat to where you want the heat in the first place.
If every building had a solar installation and a little battery then you're not powering everyone from one big facility, you're just doing top up work.
Basically, thinking about energy purely in terms of producing and consuming electricity from the grid is very shortsighted. We can do better.
posted by Just this guy, y'know at 1:48 AM on August 21, 2018 [7 favorites]
Or I guess you could just move the server farms making the heat to where you want the heat in the first place.
I see that they moved from heating individual rooms with servers replacing central heating radiators (one of the electricity companies here started it like that a couple of years back; this is a spin-off) to a central device substituting or augmenting your existing heating system. But from a quick look they don't appear to have documentation about the physical equipment; it's all about the software/cloud side of things.
A friend of mine is keeping a nuclear telecoms bunker now operating as a museum warm by running cryptocoin miners. Originally it was all electrically heated anyway, with wartime power provided by a diesel generator. The 'thermostat' basically controls the number of active miners.
posted by Stoneshop at 3:13 AM on August 21, 2018
I see that they moved from heating individual rooms with servers replacing central heating radiators (one of the electricity companies here started it like that a couple of years back; this is a spin-off) to a central device substituting or augmenting your existing heating system. But from a quick look they don't appear to have documentation about the physical equipment; it's all about the software/cloud side of things.
A friend of mine is keeping a nuclear telecoms bunker now operating as a museum warm by running cryptocoin miners. Originally it was all electrically heated anyway, with wartime power provided by a diesel generator. The 'thermostat' basically controls the number of active miners.
posted by Stoneshop at 3:13 AM on August 21, 2018
One idea that I think is really elegant is to let people allocate a certain percentage of their electric car's charge capacity for grid use, so that when it's needed the car can sell power (generated by a residential-scale PV installation, ideally) to the grid. Same could quite easily go for household battery backup systems—when they're not needed to power your home during a blackout, they could be providing peaking power to the grid as necessary, and you (the homeowner) would get the benefits.
Of course, the issue here is that as the utilities own and maintain the grid, they somewhat rightly feel that individual homeowners shouldn't be able to just sell as much energy as they want. In my state for instance, you can get a credit on your utility bill for energy produced but you never actually get paid money. The solution there, of course, is to nationalize the utility companies.
posted by Anticipation Of A New Lover's Arrival, The at 5:05 PM on August 21, 2018 [1 favorite]
Of course, the issue here is that as the utilities own and maintain the grid, they somewhat rightly feel that individual homeowners shouldn't be able to just sell as much energy as they want. In my state for instance, you can get a credit on your utility bill for energy produced but you never actually get paid money. The solution there, of course, is to nationalize the utility companies.
posted by Anticipation Of A New Lover's Arrival, The at 5:05 PM on August 21, 2018 [1 favorite]
Of course, the issue here is that as the utilities own and maintain the grid, they somewhat rightly feel that individual homeowners shouldn't be able to just sell as much energy as they want.
Here (NL) there's no such restriction, but you get less per sold kWh than what you pay when buying. Which makes sense, as part of the energy cost is infrastructure.
In Germany there's a restriction that if you have local storage the amount of energy you are allowed to feed back is limited, although I'm not clear on the details.
posted by Stoneshop at 10:35 PM on August 21, 2018
Here (NL) there's no such restriction, but you get less per sold kWh than what you pay when buying. Which makes sense, as part of the energy cost is infrastructure.
In Germany there's a restriction that if you have local storage the amount of energy you are allowed to feed back is limited, although I'm not clear on the details.
posted by Stoneshop at 10:35 PM on August 21, 2018
I've heard closed mines suggested as a potentially less hazardous option for pumped hydro than elevated reservoirs (using the difference in depth between upper and lower branches), as well as natural compressed air tanks. The article mentions compressed air in passing, but makes it sound like there isn't much progress being made.
Some closed mines are usable as hyrdo plants just from draining seasonal runoff. To get a sense of the kind of storage space available in these, here's an old photo of a model of the mine from that story, with the Empire State Building for scale.
posted by snuffleupagus at 11:04 PM on August 21, 2018
Some closed mines are usable as hyrdo plants just from draining seasonal runoff. To get a sense of the kind of storage space available in these, here's an old photo of a model of the mine from that story, with the Empire State Building for scale.
posted by snuffleupagus at 11:04 PM on August 21, 2018
You could even live on top of it!
Heindl's energy storage calculations take the cylinder's lift the same as its radius. So you would need a way to deal with a 60m (smallest) to 500m (largest) variation in height for access and utilities. The smallest could be doable, and its area would offer four or five large (for EU standards) housing plots.
You just have to synchronise your working hours with the height of the cylinder if you commute by bike, so that you leave for work at a time when it's extended and return when it's flush.
Not quite unrelated: there's a house here in NL that rotates so that the living room windows stay facing the sun. The 'utility core' (bathroom, kitchen, boiler room) is stationary at the center. And the garden path ends in a semicircle to allow for the changing position of the front door.
posted by Stoneshop at 3:37 AM on August 22, 2018 [2 favorites]
Heindl's energy storage calculations take the cylinder's lift the same as its radius. So you would need a way to deal with a 60m (smallest) to 500m (largest) variation in height for access and utilities. The smallest could be doable, and its area would offer four or five large (for EU standards) housing plots.
You just have to synchronise your working hours with the height of the cylinder if you commute by bike, so that you leave for work at a time when it's extended and return when it's flush.
Not quite unrelated: there's a house here in NL that rotates so that the living room windows stay facing the sun. The 'utility core' (bathroom, kitchen, boiler room) is stationary at the center. And the garden path ends in a semicircle to allow for the changing position of the front door.
posted by Stoneshop at 3:37 AM on August 22, 2018 [2 favorites]
there's a house here in NL that rotates so that the living room windows stay facing the sun.
COOL. Any more deets?
posted by aspersioncast at 9:06 AM on August 25, 2018
COOL. Any more deets?
posted by aspersioncast at 9:06 AM on August 25, 2018
https://www.nrc.nl/nieuws/2017/02/17/opstaan-en-gaan-slapen-met-de-zon-6741280-a1546340
I ran it trough Google Translate and it's totally comprehensible, if not flawless.
What I remembered about the stationary core was from earlier houses in the US, apparently built that way to allow housewives to keep watching their children. Which sounds rather far-fetched, but whatever turns one's crank.
If I were to design such a house I would probably go for a stationary core myself, solving a few potential problems with utility feeds and sewerage. The smaller drain from a kitchen sink can be made flexible enough to connect with a stationary drain at the centre so that you can have the kitchen on the outside as well. Plumbing for water and heating* isn't a problem either if movement is only through 180 degrees or so, and slow, and not being able to find the bathroom door in the middle of the night is solvable.
* My first thought was hot air heating, but that's quite uncommon for domestic over here.
posted by Stoneshop at 12:05 PM on August 25, 2018
I ran it trough Google Translate and it's totally comprehensible, if not flawless.
What I remembered about the stationary core was from earlier houses in the US, apparently built that way to allow housewives to keep watching their children. Which sounds rather far-fetched, but whatever turns one's crank.
If I were to design such a house I would probably go for a stationary core myself, solving a few potential problems with utility feeds and sewerage. The smaller drain from a kitchen sink can be made flexible enough to connect with a stationary drain at the centre so that you can have the kitchen on the outside as well. Plumbing for water and heating* isn't a problem either if movement is only through 180 degrees or so, and slow, and not being able to find the bathroom door in the middle of the night is solvable.
* My first thought was hot air heating, but that's quite uncommon for domestic over here.
posted by Stoneshop at 12:05 PM on August 25, 2018
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Upon reflection, kinetic batteries like this are nothing new. I wonder where else they have been used?
posted by rebent at 10:25 AM on August 20, 2018 [1 favorite]