Swiss "water battery" with 20 million kWh of capacity is finally functional

Shawn Knight

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In context: It's taken Switzerland €2 billion and 14 years, but the country's underground "water battery" is now complete and operational. The project took so long to complete in part because workers had to tunnel through more than 11 miles of the Swiss Alps.

A hydro battery is comprised of two large bodies of water at different heights – in this instance, they are located nearly 2,000 feet below ground between the Emosson and Vieux Emosson dams in Valais.

Excess energy can be used to pump water from the lower basin to the higher pool. When power demand increases, water in the higher pool is allowed to flow back into the lower reservoir. As the water flows, it spins turbines which generate hydroelectric power.

The power plant features six pump turbines that can generate 900 MW of power. The facility was constructed by Nant de Drance and is capable of storing 20 million kWh of electricity, which should help stabilize Switzerland's energy grid. It takes roughly 20 hours to empty out the Vieux Emosson reservoir, we're told.

Renewable energy enthusiasts have been doing a lot of outside-the-box thinking as of late.

Last month, Researchers from the International Institute for Applied Systems Analysis (IIASA) shared plans for a gravity-based system that would use elevators in high-rise buildings to generate and store electricity. Days ago, we learned that a company in Finland has created a battery that uses sand to store electricity as heat.

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Basically gravity energy storage. The Swiss are doing a lot with the concept. It's pretty neat.

This isn’t a new thing, we’ve been doing it in the states for years. See “Big Creek” hydroelectric plant. Interesting article nonetheless, I wish more places did this. Keep in mind, for that for the excess electricity, it is being generated by a fossil fuel plant. You can’t use solar panels or wind power to generate excess power during the night.. usually..
 
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I think Dinorwig Power Station in Wales is the same kind of thing, I visited there years ago, Really impressive inside the hollowed out mountain.
 
I think Dinorwig Power Station in Wales is the same kind of thing, I visited there years ago, Really impressive inside the hollowed out mountain.
It does, this isn’t anything new. However, I haven’t seen one this large before.. 11 miles is an insane amount of area for water to flow. These would be better paired with nuclear power plants IMO.
 
What about losses? What's the efficiency of this "battery"?

Gravity energy storage is very efficient, basically remove mechanical energy lost in the pumps, and then multiply whatever loss factor that is by the turbines efficiency. Not as efficient as a chemical battery, but a lot cheaper, longer lifespan, more scalable and much lower construction emissions. It is the go to solution where available for very good reason.

Also techspot that’s called a 20GWh battery. Please refrain from using millions of kWh’s. If desperate use 2 x 10^10 Wh’s.
 
What about losses? What's the efficiency of this "battery"?
They usually say to expect about 90% efficiency for this type of energy storage which is fairly efficient. This particular system with 900MW of storage isn't particularly large as there are probably 100 systems with more storage but they are a good way of storing energy.

These types of system work great when there's a nearby source of green energy to store and a nearby city or industrial centre to use the electricity. It isn't made clear in the article where the energy comes from or goes to.

The official name for this type of energy storage is called pumped hydro.
 
It does, this isn’t anything new. However, I haven’t seen one this large before.. 11 miles is an insane amount of area for water to flow. These would be better paired with nuclear power plants IMO.

I will assume they keep the pipes full then and have valves near the generators.

When I went to Dinorwig on a school trip they showed use a video of it spooling up from 0 to max power, it took like 90 seconds or something, These plants are very impressive, we use ours for when the kettles go on :)

I just realized this must have been about 1988, I don't think it had even been running that long at that time.
 
There is a proposal for one or more here in NZ to even electricity
https://www.mbie.govt.nz/building-a...ssions-economy/nz-battery/lake-onslow-option/

You just have to find the right geographical features

As an aside apparently our neighbours Australia has a big solar farm that's built with no transmission structure to use it

There were dreams decades ago of high transmission superconductors - ie near zero power loss - Sahara Solar panels to Europe .
Whoever makes the perfect battery for cheap will be rich
Us doomsday preppers can close down our chicken/pig manure generators and EV our all terrain assault vehicles
 
They usually say to expect about 90% efficiency for this type of energy storage which is fairly efficient. This particular system with 900MW of storage isn't particularly large as there are probably 100 systems with more storage but they are a good way of storing energy.

The official name for this type of energy storage is called pumped hydro.

According to Wikipedia, 70% to 80% efficiency is more like it. consistent with hydro schemes in general.
 
So they built another dam and paired it with hydroelectricity, as should be expected. I fail to grasp what is new about this damn water battery.
I believe they use energy to store the water In a higher gravity reservoir then when energy is demanded like a battery the water naturally through gravity will make it to the lower reservoir generating electricity in the process. So you technically have to store the water using energy to use that energy at a later time like a battery.
 
I believe they use energy to store the water In a higher gravity reservoir then when energy is demanded like a battery the water naturally through gravity will make it to the lower reservoir generating electricity in the process. So you technically have to store the water using energy to use that energy at a later time like a battery.
Absolutely. Otherwise, they would have some sort of perpetual motion machine which is impossible according to our understanding of physics..

This article really does not make it clear, however, it does mention that the plant features "six pump turbines" which, to me, implies that the turbines that generate electricity are also run in reverse (by applying power to them) effectively acting as pumps to fill the upper chamber when it is empty.
 
There were dreams decades ago of high transmission superconductors - ie near zero power loss - Sahara Solar panels to Europe .
Whoever makes the perfect battery for cheap will be rich
Us doomsday preppers can close down our chicken/pig manure generators and EV our all terrain assault vehicles
And there are still dreams of superconductors today complete with many researchers still looking at finding a room-temperature superconductor. If they do find one, energy production and transmission will change - along with life on Earth.

And, I am sure you know, there is a substantial amount of research into better batteries, too. For instance, your neighbors in Australia are doing research and pilot production on aluminum batteries - which stand a chance of being a substantial improvement over Lithium batteries in several ways - https://graphenemg.com/energy-storage-solutions/aluminum-ion-battery/
 
Gravity energy storage is very efficient, basically remove mechanical energy lost in the pumps, and then multiply whatever loss factor that is by the turbines efficiency.
Plus evaporative losses, which can be quite large.

Still, pumped hydro is at present the only practical method of storing the vast amounts of energy required to operate a grid based primarily on variable sources like wind and solar. Unfortunately, large-scale pumped hydro requires dams ... and environments oppose dams as much or even more than they do fossil fuels.

And, of course, if we build the dams, we don't need the wind and solar in the first place -- there's enough untapped hydro capacity in Canada alone to power all of North America's electricity needs.
 
Gravity, pressure, heat, what else? Virtually countless ways to store energy utilizing these natural phenomena really, anyone can build one, even if not exactly efficient, still a great thing to do.
 
Here's great example of how the Govt. could REQUIRE those that are fracking to develop this technique, particularly since they leave the ground water polluted and otherwise useless ... Come on Joe Biden, add this one to your so-called energy plan!
 
Seems to be a tremendous waste, a whopping 20 hours of electricity until it's empty! For $2+ billion you could have so much more. Plus, the efficiency can't be much compared to the energy consumed filling it....smoke and mirrors IMO.
 
This is a cool project but I'm not sold on the idea.

I suspect that the total carbon footprint of building this thing was enormous. Tunneling through eleven miles of solid rock. Carving out enormous chambers 2000 feet underground. How much carbon was created just moving the stone? And the concrete? Making one ton of cement produces roughly one ton of CO2, because they have to fire it to 1400C.

The pumps required to pump the water uphill will significantly increase maintenance costs. Will workers need to take an eleven mile train ride just to reach the site? It would be interesting to see a ten year carbon footprint comparison between this and a coal energy plant with similar power delivery.

The renewable energy industry sometimes has hidden carbon costs that make it a wash. Sure, you save carbon by using a windmill instead of burning coal. But when you factor in the backup systems to make up for inherent shortfalls of renewable energy, the carbon balance moves the other way.

It's like EVs. The carbon footprint of building an EV is MUCH higher than an IC, due mainly to the battery. It takes roughly seven years before the break-even point is reached. Most people sell their car at six years. So they're driving around thinking they're saving the world, when just the manufacturing of their car puts them seven years behind on the carbon footprint curve. Nothing is for free.
 
Here's great example of how the Govt. could REQUIRE those that are fracking to develop this technique, particularly since they leave the ground water polluted and otherwise useless ... Come on Joe Biden, add this one to your so-called energy plan!

Biden is too busy readin auto-que lines.

And investments like these are'nt cheap. Solar is'nt the answer to everything. But there's alot you can gain by making every household in the world just led based already.
 
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