Slashdot Mirror
Can Hoover Dam Become a Giant $3B Battery? (cleantechnica.com)
The Los Angeles Department of Water and Power wants to spend $3 billion to pump back the water that's flowing through Hoover Dam -- so it can flow through again later, during periods of peak energy demand. This generates a net profit for the dam's operators -- the pumping stations are powered by cheap solar and wind energy, while the dams are currently operating at just 20% of their capacity. An anonymous reader quotes Clean Technica:
The problem is that California has so much renewable energy available now, thanks in large measure to aggressive state mandated policies, that much of it is "constrained." That's utility industry speak for having to give it away or simply let it go to waste. In some cases, utilities in California actually pay other utility companies to take the excess electricity off their hands.
Why not store it all in some of Elon Musk's grid scale batteries? Simply put, pumped hydroelectric storage is cheaper than battery storage, at least for now. Lazard, the financial advisory and asset management firm, estimates utility scale lithium-ion batteries cost 26 cents per kilowatt-hour compared with 15 cents for pumped hydro storage. "Hoover Dam is ideal for this," Kelly Sanders, an assistant professor of civil and environmental engineering at the University of Southern California tells the New York Times. "It's a gigantic plant. We don't have anything on the horizon as far as batteries of that magnitude."
Why not store it all in some of Elon Musk's grid scale batteries? Simply put, pumped hydroelectric storage is cheaper than battery storage, at least for now. Lazard, the financial advisory and asset management firm, estimates utility scale lithium-ion batteries cost 26 cents per kilowatt-hour compared with 15 cents for pumped hydro storage. "Hoover Dam is ideal for this," Kelly Sanders, an assistant professor of civil and environmental engineering at the University of Southern California tells the New York Times. "It's a gigantic plant. We don't have anything on the horizon as far as batteries of that magnitude."
That was also prior to the CA aqueduct along I5. CA's water management is much more developed than it was back then. This idea is very straightforward, top off the battery with the "wasted" power and use it when needed.
Any amount is a net gain, it doesn't have to charge it back "all the way"
That's not true. The power plant was built along with the original structure. The dam was completed in 1935. In 1936 the water level in Lake Mead became high enough to begin power generation. Additional generators were added in 37 and 39. The final generator was added in 61, which might be where your confusion comes from.
Yes, this makes perfect sense in the right location. Mountains with the right geography, and of course building the dam flooded 100 square miles. So where you have just the right geography, and you don't mind destroying everything upstream for hundreds of square miles, at can make sense. Well, except consider Banqiao.
As Banqiao and other dams show, you also need to be okay with destroying everything downstream for many miles. Given all those conditions, it works well. Hoover dam is one of very few places in the US where it's a good fit.
Except wind and solar are orders of magnitude cheaper and easier in every way than nuclear, but other than that yeah you're right.
Orders of magnitude? Citation needed. Here's mine:
https://www.instituteforenergy...
On shore wind, nuclear, and coal are all about the same cost, within the error bars of each other. Solar is expensive, and needs storage to follow load, making it cost even more. Wind also needs storage but if coupled with natural gas (the cheapest means we have to produce electricity right now), coal, and nuclear then it's a viable energy source. Assuming the goal is reducing CO2 then we'll rule out coal, leaving nuclear (a tiny fraction of CO2 compared to coal) and natural gas (about half the CO2 of coal), as backup for the wind. But, as the article points out, the problem with wind is the lack of storage. Here's the solution...
Fuel is storage.
With a mix of wind, nuclear, and natural gas we can get energy that is inexpensive, low CO2, and reliable. This means that states like California would have to start building new nuclear power plants and natural gas burning power plants to go along with the wind power. Sure, California is a sunny place so maybe they have locations where solar is as cheap as the rest so go with it if it makes sense.
The problem is storage and California has been destroying their storage capacity with the shutting down of coal, natural gas, and nuclear power. Stop doing that and the problem disappears.
I am armed because I am free. I am free because I am armed.
The Colorado River has many dams. Not very far down the river from Hoover Dam is Davis Dam and Lake Mohave. By pumping water from Lake Mohave to Lake Mead (behind Hoover Dam), they would be releasing the same amount of water while storing excess solar power.
This is a very unusual situation. You have two large reservoir forming dams next to each other on a large river cutting through a desert with great solar power generating potential.