12 ms·

Pumped-storage hydroelectricity

92 points by luu 2y ago

ggm 2y ago
They can be hugely political. Snowy 2.0 has tripled in price and has been a political weapon between coal, gas and renewable energy investment. It has pretty torrid engineering troubles with tunnel boring. It will be late coming onstream. Some argue the money could be better spent on renewable, batteries and poles and wires. The Queensland proposal at Kidston has become a pawn between two parties and probably won't go ahead as large, if at all. Queensland's existing PHES was operated by the coal generator to earn it money in coal, not to reduce pricing in bids by undercutting. The government had to structurally separate it out to get better bidding outcomes noting that it co-owns the coal power station concerned and liked the revenue side as it is. Pumped hydro can be very useful in "black start" events.
- beachy 2y ago
  Political is right. In NZ, the Onslow pumped hydro scheme was just cancelled by the incoming right wing-ish government, with no comprehensible rationale given [0] > “On top of its $16 billion price tag, the Lake Onslow scheme would run into likely issues with consenting and it wouldn’t be delivered for at least another decade. It will cost a lot and take a while. Duh. Show me the numbers. And govt can modify the consenting regime. > “Industry experts warned that if the scheme went ahead it would have a chilling effect on the pipeline of renewable electricity generation New Zealand needs to reach our climate goals. Please explain how something that can store renewable electricity has a chilling effect on renewables. [0] https://www.beehive.govt.nz/release/lake-onslow-pumped-hydro-scheme-scrapped https://www.beehive.govt.nz/release/lake-onslow-pumped-hydro...
  - ggm 2y ago
    By under bidding its energy against renewables, earned from gas and coal? I don't entirely understand it either but the same reasoning is used by green opposition to snow2.0 to argue against it, a product of the turnbull LNP era government. Damage to the national park during construction is the icing on the cake.
  - zizee 2y ago
    The Onslow pumped hydro scheme is estimated to store 4,000 – 11,000 GWh, with an estimated cost of $16 billion NZD (9.7 billion USD), and be delivered in (at least) 10 years time. Is that a cost of $881-2450 USD per kwhr? I presume there is ample room for cost blowouts as well. LiPo cells are currently costing about $110 to 130/kWh (USD), and trending downwards. Now large scale storage batteries are more than just the cells (Tesla megapacks are selling for 1.39M for 3.916 MW or about $410/kwhr), and cells probably wear out quicker than a dam, but it seems the Onslow scheme is not giving great bang for buck. The best you could say for it is that a lot of the spend would stay in NZ because a lot of the spend is in labour. Am I missing something? Is my math wrong? It seems to me spending 16 billion becoming experts in assembling large scale batteries would be a better long term investment for NZ. And they can get access to the storage as it is build, instead of waiting 10 years. https://www.mbie.govt.nz/dmsdocument/28349-identifying-potential-sites-for-large-scale-pumped-hydroelectric-energy-storage-phes-in-new-zealand-september-2021 https://www.mbie.govt.nz/dmsdocument/28349-identifying-poten... https://pv-magazine-usa.com/2024/03/06/battery-prices-collapsing-grid-tied-energy-storage-expanding/ https://pv-magazine-usa.com/2024/03/06/battery-prices-collap... https://en.m.wikipedia.org/wiki/Tesla_Megapack https://en.m.wikipedia.org/wiki/Tesla_Megapack
    - jltsiren 2y ago
      Your math is off by three orders of magnitude. The scale of the Onslow pumped hydro scheme is in billions of kWh, not in millions of kWh.
      - chickenbig 2y ago
        https://cdn.auckland.ac.nz/assets/business/about/our-research/research-institutes-and-centres/energy-centre/summerschool/2021presentations/day2-m-taylor.pdf https://cdn.auckland.ac.nz/assets/business/about/our-researc... Indeed the above puts it as having 8TWh storage capacity (and perhaps 1.2GW power). Longer duration storage, with low cost to hold the energy (which hopefully does not evaporate too much during the bountiful times).
      - zizee 2y ago
        Thanks for the correction. So this pumped hydro storage is at least 200x cheaper per kWh than current LiPo based solutions.
  - robbiep 2y ago
    Meanwhile your neighbours over here created a political foil in the shape of nuclear reactors and are coming in swinging for a presumptive election this year saying that is the way forward
  - slyall 2y ago
    The incoming government didn't cancel the scheme. They cancelled the investigation into the scheme which was due to report in late-2024 (I think). The investigation would have covered other options as well. They didn't save billions, they save a million and threw away the work done
- ZeroGravitas 2y ago
  There's definitely politics involved, but also the prices of solar, wind and batteries are and have been steadily falling. One mental blindspot when comparing storage is to assume you need X amount of stored energy, but of course no-one wants stored energy, they just want energy. Storing it only makes sense if you can't generate it for less so you need to compare against a portfolio of generation and short term storage. If you can't beat that on economics then you're useless, even if no other tech can beat you at your specific task of long duration storage.
  - wongarsu 2y ago
    Most pumped hydro is short-ish term storage and at full capacity runs from full to empty within 10-20 hours. And in a new development there's nothing really stopping you from putting in more pipes and generators so you can get the full energy out in half the time if that makes more economic sense. Conceptually they are like batteries, just with the ability to scale max discharge rate and max capacity somewhat independently, a much lower cost per MWh stored, but high engineering complexity because each site needs a bespoke solution. Of course there are some projects that just go for huge storage and few generators. Sometimes they serve another purpose and just have generators as a side benefit. And sometimes they don't make a lot of sense and seem to just be built that way to be more impressive
  - energy123 2y ago
    At least as of a year ago, pumped hydro was cost competitive with lithium ion batteries and filled the 10 hour niche. The other benefits are longer lifespan and domestic construction. Lithium ion batteries filled the sub-10 hour niche. But lithium ion battery costs will keep falling and pumped hydro costs won't fall or will increase alongside rising labour costs and gutted state capacity. So there could be a crossover point if it hasn't already happened.
    - AndrewDavis 2y ago
      > But lithium ion battery costs will keep falling I question whether increased demand for grid scale batteries will create so much demand that lithium won't drop significantly any time soon. I certainly hope i'm wrong.
- femto 2y ago
  One worth mentioning in this context is the Western Sydney Pumped Hydro Project. It sounds like a no-brainer. It uses the existing Lake Burragorang (formed by Warragamba Dam) and an existing hole with infrastructure at the old Wollondilly Coal Washery, 400m above the lake and 3.1km from it. It will offer 8GWh of storage, close to Sydney, basically for the effort of digging a 3.5km tunnel and installing turbines. https://www.waternsw.com.au/water-services/renewable-energy-and-storage-program/Western-Sydney-Pumped-Hydro-Project https://www.waternsw.com.au/water-services/renewable-energy-... To their credit, Sydney Water has a range of projects based on adding pumped hydro to exiting dams, of which the above is one. Total storage capacity of projects announced to date is 25GWh. They seem ideal for firming rooftop solar around Sydney/Newcastle/Wollongong. https://www.waternsw.com.au/water-services/renewable-energy-and-storage-program https://www.waternsw.com.au/water-services/renewable-energy-...
  - robbiep 2y ago
    The western sydney project is a no brainer. It’s being independently financed and run I think? Some mac banker saw and opportunity and ran with it
Gys 2y ago
Would this also be 70-80% efficient on a smaller scale? Our land has a few meters elevation so I could create a 'pond' at the high end.
- ben_w 2y ago
  Probably about the same efficiency, but be aware the energy density for gravity storage is terrible. Every cubic meter of water you raise by 1 meter, stores about enough to charge an iPhone 15 by 20%. http://www.wolframalpha.com/input/?i=1000kg%20%2A%209.8m%2Fs%2Fs%20%2A1m%20in%20Wh http://www.wolframalpha.com/input/?i=1000kg%20%2A%209.8m%2Fs...
  - Titan2189 2y ago
    I was getting ready to write an angry comment that you've got an error in your thinking / maths, because my intuition tells me that doesn't feel right. I've run the numbers myself and am still in disbelief that raising 1,000 kg by 1 meter is the energy equivalent of an AA battery (= 20% iPhone 15 charge)
    - konschubert 2y ago
      If it was any more than that, electric cars would not be able to drive up a mountain.
    - Mistletoe 2y ago
      It’s also why if you’ve ever had a well, you discover how cheap it is to have your own water source compared to paying for municipal water. You just pay for the electricity to pump it up to your faucet, and the electricity to charge an AA battery is quite cheap.
      - ben_w 2y ago
        I suspect most people have never had a well. One of the first indicators my family had about my grandmother's Alzheimer's was an Easter lunch in a small village, where she suggested the village was not connected to the water main and the residents probably still used wells — that was about 15 years ago when she was about 90. Part of the justification for price difference between wells and municipal water also comes with guarantees from the latter about it being clean and free from contamination, and that they'll treat your waste water. How much this happens in practice… well (no pun intended), I'll leave that to news stories about Flint's flammable water and Thames Water's sewage discharges.
patapong 2y ago
This map provides an interesting overview over the electricity sources used in Europe: https://app.electricitymaps.com/map https://app.electricitymaps.com/map I found it very interesting that pumped hydro is contributing a small but not insignificant portion of energy in a lot of countries, including Germany and France.
- swarnie 2y ago
  Can anyone explain what's going on in America's western regions? My very naïve understanding is these places have giant deserts the size of some countries, shouldn't they be tripping over solar farms and have much lower carbon intensity?
  - happosai 2y ago
    They went full retard on politics and decided climate change isn't a thing. Or if it is, it is someone else's problem. "Look at the huge emissions of China and India - nevermind the CO2/Capita numbers that makes us the bad guy".
    - htthbjk 2y ago
      [dead]
    - api 2y ago
      CO2/capita numbers matter from an assigning blame point of view, but physics doesn't care if a ton of CO2 is emitted by one person or ten people. It's a bad argument to do nothing, but it's also not completely wrong. At this point we could turn off Europe and the USA and would still blow past 800ppm CO2 by 2100.
      - TremendousJudge 2y ago
        Would it work that way? A non-trivial portion of the emissions of those countries are caused by manufacturing products that are exported to the US and Europe
hydrox24 2y ago
If people are interested in pumped hydro, Andrew Blakers et. al. from ANU have put together a global atlas of potential pumped hydro sites. They've got greenfield, brownfield, etc. https://re100.eng.anu.edu.au/pumped_hydro_atlas/ https://re100.eng.anu.edu.au/pumped_hydro_atlas/
- unwind 2y ago
  That is already mentioned, in the fifth paragraph of the posted Wikipedia page (reference 8).
pydry 2y ago
There are two incredibly common wrong assumptions made about pumped storage: * It doesnt exist. Nobody says this outright of course but solar and wind skeptics often choose to "assume" that only more expensive lithium ion batteries can store power generated by solar or wind and "forget" about pumped hydro, being up to 3x cheaper. * The geography for it is rare. The geography for hydroelectric dams which can also be used as pumped storage IS rare, because undammed dammable rivers are not common. However, for pumped storage it's not the case. In both cases there are certain lobbies whom I think have a vested interest in perpetuating these false assumptions - the same way false assumptions about, say, wind turbines and bird deaths are perpetuated by people like Trump.
- robertlagrant 2y ago
  > the same way false assumptions about, say, wind turbines and bird deaths are perpetuated by people like Trump I've not heard this one - what's it referring to?
  - pydry 2y ago
    https://www.newsweek.com/fact-check-are-thousands-bald-eagles-killed-wind-turbines-1778304 https://www.newsweek.com/fact-check-are-thousands-bald-eagle...
    - misja111 2y ago
      Thanks for the link! But, after reading the article, it seems that Trump's assumptions about bird killings were true? Apparently US windmills kill hundreds of thousands of birds every year. Among them hundreds of bald eagles. So over time that adds up to thousands.
      - fred_is_fred 2y ago
        The falsehood here is that only wind mills kill animals. Coal mines, especially strip and mountain removal mines kill plenty of wildlife. Oil refineries also do, as do turbines in hydro dams. There's no energy source we have that is zero impact.
gorbypark 2y ago
I worked in the snowmaking industry at ski resorts for more than a decade before getting into tech. Many ski resorts have a snowmaking reservoir at elevation and a pumping system to fill it (usually off peak) and then use gravity to actually feed the snowmaking guns (at least partially). Almost every snowmaking manager (that I talked to) has had the idea at some point to try some sort of pumped hydro offset, but I'm unaware of anyone who has actually tried it. It would be fairly small scale (reservoirs can be ~20 million gallons, usually less) but it would be interesting to see the economics of it because the infrastructure is already there (pumps, pipes, reservoirs, etc). The systems generally even sit unused for 7-8 months of the year. I think some of the challenges are that while most resorts have a fairly massive pumping system, it's usually geared towards slowly filling the reservoir, with the rest direct feeding the snow guns. Not many places have the need to fill a 20 million gallon reservoir in a couple of days. There's also the probability that the head pressure's wouldn't work out. Gravity feeding from an upper reservoir near the top of a large mountain can result in thousands of PSI at the bottom if not passed through a series of pressure relief valves. I'd imagine ideally you would have to build a generating station and a new catch reservoir at the perfect elevation because if you are pumping a lot higher than needed the efficiency is going to drop significantly.
- pbmonster 2y ago
  > I'd imagine ideally you would have to build a generating station and a new catch reservoir at the perfect elevation because if you are pumping a lot higher than needed the efficiency is going to drop significantly. I don't think that's a concern. There's hydro plants with more than 6000' of head, leading to almost 3000 psi of pressure at the turbine and an exit velocity of the water jet of over 600 ft/s. From an engineering standpoint its totally manageable, and results in a highly efficient turbine. > I think some of the challenges are that while most resorts have a fairly massive pumping system, it's usually geared towards slowly filling the reservoir, with the rest direct feeding the snow guns. Not many places have the need to fill a 20 million gallon reservoir in a couple of days. Good news is that adding another pipe with its own pump/generator is relatively cheap. Bad news is that 20 million gallons is a relatively small reservoir for pumped hydro, and increasing that is expensive. Still, seems like an easy and fast way to get some additional capacity online, especially in cases where a couple of megawatt of new solar get build in the vicinity of that damn...
openrisk 2y ago
> Closed loop (off-river) pumped hydro storage has the smallest carbon emissions per unit of storage of all candidates for large-scale energy storage Pumped-storage is a rather special approach as it feels almost like an extension of the natural water cycle. Reducing the total footprint of the energy system (including all materials required for construction and ongoing maintenance) is an important part of the sustainability puzzle. Ofcourse once you scale things to the gargantuan energy needs of modern civilization all sorts of minor "side-effects" may become important.
- pluto_modadic 2y ago
  or, we should spend less electricity on AI, big data, and blockchains.
  - Maakuth 2y ago
    Even if we decided to stop all these and curtail datacenter power usage in other ways, decarbonising is certainly going to require increased electricity generation. Most oil and gas usage will be replaced with electrical alternatives. As the oil and gas burning applications are mostly quite inefficient, luckily we don't need to do 1:1 replacement of the chemical energy of fossil fuels. Still it seems unavoidable that in the future there will be more electricity generation rather than less.
fred_is_fred 2y ago
Is there a limit to the height (fall) needed to produce power? In other words does a drop of 500 feet produce the same power as a drop of 1000 feet? I assume there's a limit on how fast a turbine can spin and also a terminal velocity for water falling through a tunnel? Not sure if I am asking this right but for wind turbines for example 60 mph wind and 40 mph wind are the same, there's a limit on how quick those blades can spin.
- bluGill 2y ago
  You need stronger materials, but in general the more pressure the better.
- uboot 2y ago
  There is a limit, but it is rather high. The big constraint is the steel cladding of the shafts --- those nearly vertical tunnels are all "armored", because normal rock would not resist the pressure. The company I work for has plants with 800m ~ 2400 feet height difference running, I know of slightly higher ones in the French/Swiss Alps. Up to 1km is doable with current engineering.
- pjc50 2y ago
  > In other words does a drop of 500 feet produce the same power as a drop of 1000 feet? Because of "mgh", that halves the amount of energy you can store for a given reservoir size.
jes5199 2y ago
a thing I learned recently is that we are _already_ using hydroelectric power to balance out solar power - apparently with existing dams it's possible to dial down the flow in the daytime and dial it up at night. As more solar energy comes online, this becomes a natural consequence of energy markets
- brikym 2y ago
  You are correct. It's most efficient to first stop hydro when there is cheaper renewable generation available, then if there is still excess then pump uphill into storage. It would be silly to have water going both up and down at the same time.
- pjc50 2y ago
  Hydro is extremely throttleable; most plants can go from 0 to 100% or vice versa in a couple of minutes.
kelseyfrog 2y ago
I'll never forget the opportunity I had to visit the Helms Pumped Storage Plant. Driving directly into the side of the mountain and emerging into the generation facility was incredible. The shear size of the generators, the enormity piping, and the massive hunk of metal that are the turbine drives shafts left me reeling. Each part is large beyond belief and the fact that it's not possible to view it in one piece only adds to the scale. Simply an feat of engineering.
hndude 2y ago
NREL - National Renewable Energy Lab - interactive Pumped storage hydropower visualizer: https://maps.nrel.gov/psh https://maps.nrel.gov/psh "Provides an effective way to view the national closed-loop Pumped Storage Hydropower (PSH) resource assessment and identify potential PSH sites while considering a wide array of possible technical and environmental specifications."
eejobboard 2y ago
dabest
liampulles 2y ago
Pumped water is used quite a lot here in South Africa to help handle peak load in the national grid. It's probably going to continue to play a huge role as we transition to more solar.
- makoto12 2y ago
  i'm only aware of the one supporting cape town. do we have more for the main grid?
  - Dead_Lemon 2y ago
    Ingula Pumped Storage, KZN, 1,332MW Drakensberg Pumped Storage, FS, 1,000MW Palmiet Pumped Storage, WC, 400MW Steenbras Pumped Storage, WC, 180MW Steenbras is the only plant installed and maintained by City of Capetown, the rest are Eskom facilities (Its mentioned occasionally, by eskom, that load shedding continues over a weekend, or late evenings, to restore pumped storage for the week/productive hours) https://en.wikipedia.org/wiki/List_of_power_stations_in_South_Africa#Pumped_storage https://en.wikipedia.org/wiki/List_of_power_stations_in_Sout...
plipt 2y ago
A few years ago there was a slew of articles about storing energy by lifting and stacking heavy blocks of concrete. I have no idea how efficient those designs are compared to hydro storage but I imagine they solve a problem for regions where there is no suitable site for the water reservoir. Haven't seen that concept in the news recently, maybe it didn't pan out? https://spectrum.ieee.org/gravity-energy-storage-will-show-its-potential-in-2021 https://spectrum.ieee.org/gravity-energy-storage-will-show-i... https://www.wired.com/story/energy-vault-gravity-storage/ https://www.wired.com/story/energy-vault-gravity-storage/
- xaellison 2y ago
  It appears Enel "plans" a gravity system in ERCOT (May 2024) https://www.pv-magazine.com/2024/05/22/enel-energy-vault-build-18-mw-36-mwh-of-us-gravity-storage/ https://www.pv-magazine.com/2024/05/22/enel-energy-vault-bui...
- hannob 2y ago
  Physics isn't very kind to all these gravity-energy-storage ideas. You need very large objects and substantial height differences to store any meaningful amount of energy. While many ideas about new types of gravity-energy-storage are flaoting around, pumped hydro is the only gravity-storage technology that ever worked in practice. And even pumped hydro isn't in a great spot. Batteries are essentially competing for the same market (intra-day storage, few hours, high round-trip efficiency), and improving fast.
- AtlasBarfed 2y ago
  Lat I checked it simply costs too much to build the lifting equipment and upkeep. It isn't economical because of the tower height. Pumped hydro, assuming there isn't a huge excavation effort for the lake, is just some pipes and a turbine.
sschueller 2y ago
Here is an insane video showing how difficult it can be to dig pumped storage tunnels: https://youtu.be/6AV2NcyX7pk https://youtu.be/6AV2NcyX7pk
0wis 2y ago
Easy where there is a lot of mountains (japan, Austria, France), harder in flat countries. Interesting part of the article on electrolysis to use the lighter than air H2 instead of pumping water up. Smells a lot like over-engineering but seems fun !
Log_out_ 2y ago
imagine if you could just park an icebergmountain on a small lake..all the power of a damed lake, none of the megastructure.

92 points by luu 2y ago

ggm 2y ago

They can be hugely political. Snowy 2.0 has tripled in price and has been a political weapon between coal, gas and renewable energy investment. It has pretty torrid engineering troubles with tunnel boring. It will be late coming onstream. Some argue the money could be better spent on renewable, batteries and poles and wires. The Queensland proposal at Kidston has become a pawn between two parties and probably won't go ahead as large, if at all. Queensland's existing PHES was operated by the coal generator to earn it money in coal, not to reduce pricing in bids by undercutting. The government had to structurally separate it out to get better bidding outcomes noting that it co-owns the coal power station concerned and liked the revenue side as it is. Pumped hydro can be very useful in "black start" events.

beachy 2y ago
Political is right. In NZ, the Onslow pumped hydro scheme was just cancelled by the incoming right wing-ish government, with no comprehensible rationale given [0] > “On top of its $16 billion price tag, the Lake Onslow scheme would run into likely issues with consenting and it wouldn’t be delivered for at least another decade. It will cost a lot and take a while. Duh. Show me the numbers. And govt can modify the consenting regime. > “Industry experts warned that if the scheme went ahead it would have a chilling effect on the pipeline of renewable electricity generation New Zealand needs to reach our climate goals. Please explain how something that can store renewable electricity has a chilling effect on renewables. [0] https://www.beehive.govt.nz/release/lake-onslow-pumped-hydro-scheme-scrapped https://www.beehive.govt.nz/release/lake-onslow-pumped-hydro...
- ggm 2y ago
  By under bidding its energy against renewables, earned from gas and coal? I don't entirely understand it either but the same reasoning is used by green opposition to snow2.0 to argue against it, a product of the turnbull LNP era government. Damage to the national park during construction is the icing on the cake.
- zizee 2y ago
  The Onslow pumped hydro scheme is estimated to store 4,000 – 11,000 GWh, with an estimated cost of $16 billion NZD (9.7 billion USD), and be delivered in (at least) 10 years time. Is that a cost of $881-2450 USD per kwhr? I presume there is ample room for cost blowouts as well. LiPo cells are currently costing about $110 to 130/kWh (USD), and trending downwards. Now large scale storage batteries are more than just the cells (Tesla megapacks are selling for 1.39M for 3.916 MW or about $410/kwhr), and cells probably wear out quicker than a dam, but it seems the Onslow scheme is not giving great bang for buck. The best you could say for it is that a lot of the spend would stay in NZ because a lot of the spend is in labour. Am I missing something? Is my math wrong? It seems to me spending 16 billion becoming experts in assembling large scale batteries would be a better long term investment for NZ. And they can get access to the storage as it is build, instead of waiting 10 years. https://www.mbie.govt.nz/dmsdocument/28349-identifying-potential-sites-for-large-scale-pumped-hydroelectric-energy-storage-phes-in-new-zealand-september-2021 https://www.mbie.govt.nz/dmsdocument/28349-identifying-poten... https://pv-magazine-usa.com/2024/03/06/battery-prices-collapsing-grid-tied-energy-storage-expanding/ https://pv-magazine-usa.com/2024/03/06/battery-prices-collap... https://en.m.wikipedia.org/wiki/Tesla_Megapack https://en.m.wikipedia.org/wiki/Tesla_Megapack
  - jltsiren 2y ago
    Your math is off by three orders of magnitude. The scale of the Onslow pumped hydro scheme is in billions of kWh, not in millions of kWh.
    - chickenbig 2y ago
      https://cdn.auckland.ac.nz/assets/business/about/our-research/research-institutes-and-centres/energy-centre/summerschool/2021presentations/day2-m-taylor.pdf https://cdn.auckland.ac.nz/assets/business/about/our-researc... Indeed the above puts it as having 8TWh storage capacity (and perhaps 1.2GW power). Longer duration storage, with low cost to hold the energy (which hopefully does not evaporate too much during the bountiful times).
    - zizee 2y ago
      Thanks for the correction. So this pumped hydro storage is at least 200x cheaper per kWh than current LiPo based solutions.
- robbiep 2y ago
  Meanwhile your neighbours over here created a political foil in the shape of nuclear reactors and are coming in swinging for a presumptive election this year saying that is the way forward
- slyall 2y ago
  The incoming government didn't cancel the scheme. They cancelled the investigation into the scheme which was due to report in late-2024 (I think). The investigation would have covered other options as well. They didn't save billions, they save a million and threw away the work done
ZeroGravitas 2y ago
There's definitely politics involved, but also the prices of solar, wind and batteries are and have been steadily falling. One mental blindspot when comparing storage is to assume you need X amount of stored energy, but of course no-one wants stored energy, they just want energy. Storing it only makes sense if you can't generate it for less so you need to compare against a portfolio of generation and short term storage. If you can't beat that on economics then you're useless, even if no other tech can beat you at your specific task of long duration storage.
- wongarsu 2y ago
  Most pumped hydro is short-ish term storage and at full capacity runs from full to empty within 10-20 hours. And in a new development there's nothing really stopping you from putting in more pipes and generators so you can get the full energy out in half the time if that makes more economic sense. Conceptually they are like batteries, just with the ability to scale max discharge rate and max capacity somewhat independently, a much lower cost per MWh stored, but high engineering complexity because each site needs a bespoke solution. Of course there are some projects that just go for huge storage and few generators. Sometimes they serve another purpose and just have generators as a side benefit. And sometimes they don't make a lot of sense and seem to just be built that way to be more impressive
- energy123 2y ago
  At least as of a year ago, pumped hydro was cost competitive with lithium ion batteries and filled the 10 hour niche. The other benefits are longer lifespan and domestic construction. Lithium ion batteries filled the sub-10 hour niche. But lithium ion battery costs will keep falling and pumped hydro costs won't fall or will increase alongside rising labour costs and gutted state capacity. So there could be a crossover point if it hasn't already happened.
  - AndrewDavis 2y ago
    > But lithium ion battery costs will keep falling I question whether increased demand for grid scale batteries will create so much demand that lithium won't drop significantly any time soon. I certainly hope i'm wrong.
femto 2y ago
One worth mentioning in this context is the Western Sydney Pumped Hydro Project. It sounds like a no-brainer. It uses the existing Lake Burragorang (formed by Warragamba Dam) and an existing hole with infrastructure at the old Wollondilly Coal Washery, 400m above the lake and 3.1km from it. It will offer 8GWh of storage, close to Sydney, basically for the effort of digging a 3.5km tunnel and installing turbines. https://www.waternsw.com.au/water-services/renewable-energy-and-storage-program/Western-Sydney-Pumped-Hydro-Project https://www.waternsw.com.au/water-services/renewable-energy-... To their credit, Sydney Water has a range of projects based on adding pumped hydro to exiting dams, of which the above is one. Total storage capacity of projects announced to date is 25GWh. They seem ideal for firming rooftop solar around Sydney/Newcastle/Wollongong. https://www.waternsw.com.au/water-services/renewable-energy-and-storage-program https://www.waternsw.com.au/water-services/renewable-energy-...
- robbiep 2y ago
  The western sydney project is a no brainer. It’s being independently financed and run I think? Some mac banker saw and opportunity and ran with it

Gys 2y ago

Would this also be 70-80% efficient on a smaller scale? Our land has a few meters elevation so I could create a 'pond' at the high end.

ben_w 2y ago
Probably about the same efficiency, but be aware the energy density for gravity storage is terrible. Every cubic meter of water you raise by 1 meter, stores about enough to charge an iPhone 15 by 20%. http://www.wolframalpha.com/input/?i=1000kg%20%2A%209.8m%2Fs%2Fs%20%2A1m%20in%20Wh http://www.wolframalpha.com/input/?i=1000kg%20%2A%209.8m%2Fs...
- Titan2189 2y ago
  I was getting ready to write an angry comment that you've got an error in your thinking / maths, because my intuition tells me that doesn't feel right. I've run the numbers myself and am still in disbelief that raising 1,000 kg by 1 meter is the energy equivalent of an AA battery (= 20% iPhone 15 charge)
  - konschubert 2y ago
    If it was any more than that, electric cars would not be able to drive up a mountain.
  - Mistletoe 2y ago
    It’s also why if you’ve ever had a well, you discover how cheap it is to have your own water source compared to paying for municipal water. You just pay for the electricity to pump it up to your faucet, and the electricity to charge an AA battery is quite cheap.
    - ben_w 2y ago
      I suspect most people have never had a well. One of the first indicators my family had about my grandmother's Alzheimer's was an Easter lunch in a small village, where she suggested the village was not connected to the water main and the residents probably still used wells — that was about 15 years ago when she was about 90. Part of the justification for price difference between wells and municipal water also comes with guarantees from the latter about it being clean and free from contamination, and that they'll treat your waste water. How much this happens in practice… well (no pun intended), I'll leave that to news stories about Flint's flammable water and Thames Water's sewage discharges.

patapong 2y ago

This map provides an interesting overview over the electricity sources used in Europe: https://app.electricitymaps.com/map https://app.electricitymaps.com/map I found it very interesting that pumped hydro is contributing a small but not insignificant portion of energy in a lot of countries, including Germany and France.

swarnie 2y ago
Can anyone explain what's going on in America's western regions? My very naïve understanding is these places have giant deserts the size of some countries, shouldn't they be tripping over solar farms and have much lower carbon intensity?
- happosai 2y ago
  They went full retard on politics and decided climate change isn't a thing. Or if it is, it is someone else's problem. "Look at the huge emissions of China and India - nevermind the CO2/Capita numbers that makes us the bad guy".
  - htthbjk 2y ago
    [dead]
  - api 2y ago
    CO2/capita numbers matter from an assigning blame point of view, but physics doesn't care if a ton of CO2 is emitted by one person or ten people. It's a bad argument to do nothing, but it's also not completely wrong. At this point we could turn off Europe and the USA and would still blow past 800ppm CO2 by 2100.
    - TremendousJudge 2y ago
      Would it work that way? A non-trivial portion of the emissions of those countries are caused by manufacturing products that are exported to the US and Europe

hydrox24 2y ago

If people are interested in pumped hydro, Andrew Blakers et. al. from ANU have put together a global atlas of potential pumped hydro sites. They've got greenfield, brownfield, etc. https://re100.eng.anu.edu.au/pumped_hydro_atlas/ https://re100.eng.anu.edu.au/pumped_hydro_atlas/

unwind 2y ago
That is already mentioned, in the fifth paragraph of the posted Wikipedia page (reference 8).

pydry 2y ago

There are two incredibly common wrong assumptions made about pumped storage: * It doesnt exist. Nobody says this outright of course but solar and wind skeptics often choose to "assume" that only more expensive lithium ion batteries can store power generated by solar or wind and "forget" about pumped hydro, being up to 3x cheaper. * The geography for it is rare. The geography for hydroelectric dams which can also be used as pumped storage IS rare, because undammed dammable rivers are not common. However, for pumped storage it's not the case. In both cases there are certain lobbies whom I think have a vested interest in perpetuating these false assumptions - the same way false assumptions about, say, wind turbines and bird deaths are perpetuated by people like Trump.

robertlagrant 2y ago
> the same way false assumptions about, say, wind turbines and bird deaths are perpetuated by people like Trump I've not heard this one - what's it referring to?
- pydry 2y ago
  https://www.newsweek.com/fact-check-are-thousands-bald-eagles-killed-wind-turbines-1778304 https://www.newsweek.com/fact-check-are-thousands-bald-eagle...
  - misja111 2y ago
    Thanks for the link! But, after reading the article, it seems that Trump's assumptions about bird killings were true? Apparently US windmills kill hundreds of thousands of birds every year. Among them hundreds of bald eagles. So over time that adds up to thousands.
    - fred_is_fred 2y ago
      The falsehood here is that only wind mills kill animals. Coal mines, especially strip and mountain removal mines kill plenty of wildlife. Oil refineries also do, as do turbines in hydro dams. There's no energy source we have that is zero impact.

gorbypark 2y ago

I worked in the snowmaking industry at ski resorts for more than a decade before getting into tech. Many ski resorts have a snowmaking reservoir at elevation and a pumping system to fill it (usually off peak) and then use gravity to actually feed the snowmaking guns (at least partially). Almost every snowmaking manager (that I talked to) has had the idea at some point to try some sort of pumped hydro offset, but I'm unaware of anyone who has actually tried it. It would be fairly small scale (reservoirs can be ~20 million gallons, usually less) but it would be interesting to see the economics of it because the infrastructure is already there (pumps, pipes, reservoirs, etc). The systems generally even sit unused for 7-8 months of the year. I think some of the challenges are that while most resorts have a fairly massive pumping system, it's usually geared towards slowly filling the reservoir, with the rest direct feeding the snow guns. Not many places have the need to fill a 20 million gallon reservoir in a couple of days. There's also the probability that the head pressure's wouldn't work out. Gravity feeding from an upper reservoir near the top of a large mountain can result in thousands of PSI at the bottom if not passed through a series of pressure relief valves. I'd imagine ideally you would have to build a generating station and a new catch reservoir at the perfect elevation because if you are pumping a lot higher than needed the efficiency is going to drop significantly.

pbmonster 2y ago
> I'd imagine ideally you would have to build a generating station and a new catch reservoir at the perfect elevation because if you are pumping a lot higher than needed the efficiency is going to drop significantly. I don't think that's a concern. There's hydro plants with more than 6000' of head, leading to almost 3000 psi of pressure at the turbine and an exit velocity of the water jet of over 600 ft/s. From an engineering standpoint its totally manageable, and results in a highly efficient turbine. > I think some of the challenges are that while most resorts have a fairly massive pumping system, it's usually geared towards slowly filling the reservoir, with the rest direct feeding the snow guns. Not many places have the need to fill a 20 million gallon reservoir in a couple of days. Good news is that adding another pipe with its own pump/generator is relatively cheap. Bad news is that 20 million gallons is a relatively small reservoir for pumped hydro, and increasing that is expensive. Still, seems like an easy and fast way to get some additional capacity online, especially in cases where a couple of megawatt of new solar get build in the vicinity of that damn...

openrisk 2y ago

> Closed loop (off-river) pumped hydro storage has the smallest carbon emissions per unit of storage of all candidates for large-scale energy storage Pumped-storage is a rather special approach as it feels almost like an extension of the natural water cycle. Reducing the total footprint of the energy system (including all materials required for construction and ongoing maintenance) is an important part of the sustainability puzzle. Ofcourse once you scale things to the gargantuan energy needs of modern civilization all sorts of minor "side-effects" may become important.

pluto_modadic 2y ago
or, we should spend less electricity on AI, big data, and blockchains.
- Maakuth 2y ago
  Even if we decided to stop all these and curtail datacenter power usage in other ways, decarbonising is certainly going to require increased electricity generation. Most oil and gas usage will be replaced with electrical alternatives. As the oil and gas burning applications are mostly quite inefficient, luckily we don't need to do 1:1 replacement of the chemical energy of fossil fuels. Still it seems unavoidable that in the future there will be more electricity generation rather than less.

fred_is_fred 2y ago

Is there a limit to the height (fall) needed to produce power? In other words does a drop of 500 feet produce the same power as a drop of 1000 feet? I assume there's a limit on how fast a turbine can spin and also a terminal velocity for water falling through a tunnel? Not sure if I am asking this right but for wind turbines for example 60 mph wind and 40 mph wind are the same, there's a limit on how quick those blades can spin.

bluGill 2y ago
You need stronger materials, but in general the more pressure the better.
uboot 2y ago
There is a limit, but it is rather high. The big constraint is the steel cladding of the shafts --- those nearly vertical tunnels are all "armored", because normal rock would not resist the pressure. The company I work for has plants with 800m ~ 2400 feet height difference running, I know of slightly higher ones in the French/Swiss Alps. Up to 1km is doable with current engineering.
pjc50 2y ago
> In other words does a drop of 500 feet produce the same power as a drop of 1000 feet? Because of "mgh", that halves the amount of energy you can store for a given reservoir size.

jes5199 2y ago

a thing I learned recently is that we are _already_ using hydroelectric power to balance out solar power - apparently with existing dams it's possible to dial down the flow in the daytime and dial it up at night. As more solar energy comes online, this becomes a natural consequence of energy markets

brikym 2y ago
You are correct. It's most efficient to first stop hydro when there is cheaper renewable generation available, then if there is still excess then pump uphill into storage. It would be silly to have water going both up and down at the same time.
pjc50 2y ago
Hydro is extremely throttleable; most plants can go from 0 to 100% or vice versa in a couple of minutes.

kelseyfrog 2y ago

I'll never forget the opportunity I had to visit the Helms Pumped Storage Plant. Driving directly into the side of the mountain and emerging into the generation facility was incredible. The shear size of the generators, the enormity piping, and the massive hunk of metal that are the turbine drives shafts left me reeling. Each part is large beyond belief and the fact that it's not possible to view it in one piece only adds to the scale. Simply an feat of engineering.

hndude 2y ago

NREL - National Renewable Energy Lab - interactive Pumped storage hydropower visualizer: https://maps.nrel.gov/psh https://maps.nrel.gov/psh "Provides an effective way to view the national closed-loop Pumped Storage Hydropower (PSH) resource assessment and identify potential PSH sites while considering a wide array of possible technical and environmental specifications."

eejobboard 2y ago

dabest

liampulles 2y ago

Pumped water is used quite a lot here in South Africa to help handle peak load in the national grid. It's probably going to continue to play a huge role as we transition to more solar.

makoto12 2y ago
i'm only aware of the one supporting cape town. do we have more for the main grid?
- Dead_Lemon 2y ago
  Ingula Pumped Storage, KZN, 1,332MW Drakensberg Pumped Storage, FS, 1,000MW Palmiet Pumped Storage, WC, 400MW Steenbras Pumped Storage, WC, 180MW Steenbras is the only plant installed and maintained by City of Capetown, the rest are Eskom facilities (Its mentioned occasionally, by eskom, that load shedding continues over a weekend, or late evenings, to restore pumped storage for the week/productive hours) https://en.wikipedia.org/wiki/List_of_power_stations_in_South_Africa#Pumped_storage https://en.wikipedia.org/wiki/List_of_power_stations_in_Sout...

plipt 2y ago

A few years ago there was a slew of articles about storing energy by lifting and stacking heavy blocks of concrete. I have no idea how efficient those designs are compared to hydro storage but I imagine they solve a problem for regions where there is no suitable site for the water reservoir. Haven't seen that concept in the news recently, maybe it didn't pan out? https://spectrum.ieee.org/gravity-energy-storage-will-show-its-potential-in-2021 https://spectrum.ieee.org/gravity-energy-storage-will-show-i... https://www.wired.com/story/energy-vault-gravity-storage/ https://www.wired.com/story/energy-vault-gravity-storage/

xaellison 2y ago
It appears Enel "plans" a gravity system in ERCOT (May 2024) https://www.pv-magazine.com/2024/05/22/enel-energy-vault-build-18-mw-36-mwh-of-us-gravity-storage/ https://www.pv-magazine.com/2024/05/22/enel-energy-vault-bui...
hannob 2y ago
Physics isn't very kind to all these gravity-energy-storage ideas. You need very large objects and substantial height differences to store any meaningful amount of energy. While many ideas about new types of gravity-energy-storage are flaoting around, pumped hydro is the only gravity-storage technology that ever worked in practice. And even pumped hydro isn't in a great spot. Batteries are essentially competing for the same market (intra-day storage, few hours, high round-trip efficiency), and improving fast.
AtlasBarfed 2y ago
Lat I checked it simply costs too much to build the lifting equipment and upkeep. It isn't economical because of the tower height. Pumped hydro, assuming there isn't a huge excavation effort for the lake, is just some pipes and a turbine.

sschueller 2y ago

Here is an insane video showing how difficult it can be to dig pumped storage tunnels: https://youtu.be/6AV2NcyX7pk https://youtu.be/6AV2NcyX7pk

0wis 2y ago

Easy where there is a lot of mountains (japan, Austria, France), harder in flat countries. Interesting part of the article on electrolysis to use the lighter than air H2 instead of pumping water up. Smells a lot like over-engineering but seems fun !

Log_out_ 2y ago

imagine if you could just park an icebergmountain on a small lake..all the power of a damed lake, none of the megastructure.