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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#231

Post by dismalpedigree »

mullen wrote: post #219
roamerz wrote: post #122

Earlier quoted context omitted.

That ship has already sailed as most power producing dams have been around for long time. Removing them would destroy the (now natural) ecosystem they have created. Plus dams have way more benefits to us than the extremely clean energy they produce - not just store.

No. First off, most dams silt up, not only not of being use in storing water but also not in creating power. Second, once they silt up, whatever ecosystem there is also destroyed and artificially created ecosystems are never natural and usually are bad for local fish populations. Artificial lakes can also host a number of non-native fish and are not any benefit to the native species that should be living there. Also,…

Right. Storing water for 50M+ people and generating enormous quantities of electricity. No use at all.

Re: Why is hydroelectricity unfashionable?

#232

Post by Quillbert182 »

bpodgursky wrote: post #34
onepointsixC wrote: post #17

Hydro isn't unfashionable. We just don't have reasonable places to keep daming, so there's little really to talk about. Nuclear is unfashionable, because there's huge growth potential among wealthy industrial countries, but because it's not "liked" there's very little actual growth.

Actually the Yosemite valley has significant hydro potential.

And it better be left alone. Hetch Hetchy has already been destroyed, we should preserve what little we have left.

Re: Why is hydroelectricity unfashionable?

#233

Post by civilized »

idiotsecant wrote: post #37

Obviously hydroelectricity is massively damaging to ecosystems. My day job includes designing hydroelectric control systems and even I can admit that. That's a big part of the reason that hydro is a non-starter in much of the western world, which is probably a reasonably good thing (although there are certainly some exceptions where hydro development seems like a no-brainer to me but I digress) What's not so clear to…

Why is hydroelectricity massively damaging while hydro pumped storage is great?

Re: Why is hydroelectricity unfashionable?

#235

Post by scythe »

ClumsyPilot wrote: post #221
philipkglass wrote: post #118

Earlier quoted context omitted.

The only other contender that is even worth mentioning is compressed gas, but it seems to have neither the capacity nor the efficiency of a large hydro deployment. The largest pumped storage station in the US has a storage capacity of 24,000 MWh: https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta... There's an underground hydrogen storage project underway in Delta, Utah with a capacity of 300,000 MWh: https…

You are confusing energy storage and fuel storage. I am talking about CAES, it uses electricity to compress air and feed that into a container, like a metal cylinder or caverns lined with impermeable material. When you need electricity, you release the air through a generator and produce electricity. Hydroelectric, compressed air and batteries have round trip efficiency of ~80%. https://www.sciencedirect.com/topics/e…

Thermochemical hydrogen offers the best prospect for hydrogen production if it can be worked out, because the whole-process efficiency from solar or nuclear heat can exceed the practical limits of water electrolysis. Most recent work focuses on the copper chloride process (which uses an electrolytic step) [1]. The best purely thermal cycle is sulfur-iodine, but running the process sustainably has yet to be achieved due to the corrosive nature of the intermediates.

1: https://www.sciencedirect.com/science/article/pii/S019689041...

Re: Why is hydroelectricity unfashionable?

#236

Post by exabrial »

01100011 wrote: post #226
exabrial wrote: post #204

Earlier quoted context omitted.

I think the main reason is that not everybody has the geography conducive for pumped Hydro. Here in Kansas we have a ton of wind energy production and we’re lucky enough to have a nuclear reactor as well. It’d really be nice to store that, but we have no mountains. We have a rolling plain in the middle of the state but even the highest/lowest delta is like 200-300 ft (I made that number up).

Can you create an underground reservoir, say from an expired oil field, that is of sufficient capacity to create a pumped hydro system in concert with a ground-level reservoir?

We do have a ton of salt caverns actually, many centrally located (Hutchison, Ks if you’re interested. Great air and space museum there too oddly enough)

Re: Why is hydroelectricity unfashionable?

#237

Post by idiotsecant »

mullen wrote: post #219
roamerz wrote: post #122

Earlier quoted context omitted.

That ship has already sailed as most power producing dams have been around for long time. Removing them would destroy the (now natural) ecosystem they have created. Plus dams have way more benefits to us than the extremely clean energy they produce - not just store.

No. First off, most dams silt up, not only not of being use in storing water but also not in creating power. Second, once they silt up, whatever ecosystem there is also destroyed and artificially created ecosystems are never natural and usually are bad for local fish populations. Artificial lakes can also host a number of non-native fish and are not any benefit to the native species that should be living there. Also,…

This is a pretty incomplete understanding of the issue, there are plenty of dams where silting is not an issue at all and will serve their purpose for centuries if properly maintained. There are also dams where silting is a regular problem. A so called 'sediment bypass' is often a feature of these dams, where water is pulled from the base of the dam through a bypass to clear out silting.

It all depends on the natural hydraulic dynamics of the dam - some are better placed than others.

Re: Why is hydroelectricity unfashionable?

#238

Post by idiotsecant »

jjk166 wrote: post #107
idiotsecant wrote: post #60

Earlier quoted context omitted.

Entirely wrong. All pumped storage requires is a big high spot and a big low spot*. Take a look at this, for example: https://www.gordonbuttepumpedstorage.com/ There are a lot of good pumped storage sites out there. *exaggeration, but close enough.

It is ridiculously uneconomical to create the volume for pumped storage. For context, with 100 meters of pressure head, you'd need 25,000 olympic swimming pools worth of water to store 12 hours of electricity from a 1 GW electric plant with 70% roundtrip efficiency. At a cost of $216/cubic yard of excavation, that's over $17 Billion. If you can make 3 cents per kwh profit buying at low times and selling at high, it w…

I think you'll find the attached link is project currently in development that does exactly what you're saying is economically impossible. It clearly is not impossible to build a relatively shallow dikes on top of a butte.

Re: Why is hydroelectricity unfashionable?

#239

Post by zdw »

throwayyy479087 wrote: post #212
exabrial wrote: post #204

Earlier quoted context omitted.

I think the main reason is that not everybody has the geography conducive for pumped Hydro. Here in Kansas we have a ton of wind energy production and we’re lucky enough to have a nuclear reactor as well. It’d really be nice to store that, but we have no mountains. We have a rolling plain in the middle of the state but even the highest/lowest delta is like 200-300 ft (I made that number up).

You are spot on. Mt. Oread has 191 ft of prominence.

There's even a paper on it "Kansas Is Flatter Than a Pancake": https://www.usu.edu/geo/geomorph/kansas.html

Re: Why is hydroelectricity unfashionable?

#240

Post by tedunangst »

01100011 wrote: post #226
exabrial wrote: post #204

Earlier quoted context omitted.

I think the main reason is that not everybody has the geography conducive for pumped Hydro. Here in Kansas we have a ton of wind energy production and we’re lucky enough to have a nuclear reactor as well. It’d really be nice to store that, but we have no mountains. We have a rolling plain in the middle of the state but even the highest/lowest delta is like 200-300 ft (I made that number up).

Can you create an underground reservoir, say from an expired oil field, that is of sufficient capacity to create a pumped hydro system in concert with a ground-level reservoir?

Still need a place to keep all the water after you pump it out of the cave.
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