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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#321

Post by ClumsyPilot »

philipkglass wrote: post #229
ClumsyPilot wrote: post #221

Earlier quoted context omitted.

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…

The facility you linked produces and stores chemical fuel, and can't even convert it back into electricity. The project includes using Mitsubishi M501JAC combined-cycle gas turbines to turn the hydrogen back into electricity: https://www.powermag.com/aces-deltas-giant-utah-salt-cavern-... https://power.mhi.com/products/gasturbines/lineup/m501j This turbine has a rated combined-cycle efficiency of 64%. Production of h…

why are turbines used in place of potentially more efficient fule cells?

Re: Why is hydroelectricity unfashionable?

#322

Post by cinntaile »

pclmulqdq wrote: post #128
cinntaile wrote: post #69

Earlier quoted context omitted.

What's your definition of destroy and do you have any examples of ecosystems that were destroyed by wind and solar?

Cutting down large swathes of forest and building over the habitats of endangered species happen for both. Solar and wind farms both need large land clearances in areas that have a lot of their respective kind of energy, which animals also use. Solar farms do best in deserts, which tend to be habitats for species that like extreme conditions. Several of them have been blocked in recent years. There was a recent huge…

Pretty much any human activity affects the ecosystem of animals and plants. It's a matter of weighing the pro's and the cons.

You link to an article from 2010, I don't exactly know which plant you refer to but I did find that a solar plant (Ivanpah) was built around that time and this was done by taking into account the tortoise territory. They decided not to build where the tortoise territory was. There is also recent work being done by environmentalists to help guide solar panel placement in the Mojave desert. https://medium.com/wild-without-end/the-tortoise-and-the-sol...

> These are also often endangered species. The fish and wildlife survey estimates 140,000-500,000 bird deaths at wind farms per year, with most of these being birds of prey which have low birth rates and high conservation value (many endangered species).

The article you linked mentions 573k birds and 80k being birds of prey, that's 14% and not "most". It also mentions there is a need for better measuring methods, it's a bit old now so they likely have gotten better at it too. This is an area of active research so efforts to reduce birds collisions are being worked on.

Re: Why is hydroelectricity unfashionable?

#323

Post by cinntaile »

pclmulqdq wrote: post #210
kennend3 wrote: post #189

Earlier quoted context omitted.

At the end of the day, the real issue is "NIMBY". Solar - sure we will protest that: https://barrie.ctvnews.ca/solar-project-demonstration-in-tay... Wind - yep... people will protest that: https://toronto.ctvnews.ca/ontario-wind-power-opponents-prot... Nuclear? Of course: https://globalnews.ca/news/4298298/protesters-rally-pickerin... So.. when those people go home, what do they think powers the lights?

Different people protest each thing. The only thing nobody is protesting is natural gas, which is green in Germany.

This is not true. People protest against everything, gas is no exception. https://www.cbc.ca/news/world/germany-lng-energy-crisis-1.65...

Re: Why is hydroelectricity unfashionable?

#324

Post by pencilguin »

nomel wrote: post #319
pencilguin wrote: post #262

Earlier quoted context omitted.

Industrial-scale electrolysers will soon be well over 90% efficient.

Any terms I can search to understand these advances? I seemed to remember learning that boring old electrolysis was around 30% efficient!

https://www.nature.com/articles/s41467-022-32652-y

Presuming I understood correctly.

Another system used a hydrogen-side electrode made of foamed metal immersed in water, where the surface area presented to the water was therefore very large, and the small pore size limited the hydrogen bubbles' interference with contact between water and electrode surface.

Re: Why is hydroelectricity unfashionable?

#325

Post by _h3p0 »

DocTomoe wrote: post #304
tialaramex wrote: post #124

Earlier quoted context omitted.

> I understand that hydroelectricity is used to supply the basic power need, say 80% and a water reservoir with turbines to cover power peak needs This seems like you either didn't understand what pumped storage is, or you've confused several related technologies. A typical pumped storage scheme goes like this: We find a mountain with a high lake and a low lake. We dam the high lake so that its natural outflow (perha…

> This seems like you either didn't understand what pumped storage is, or you've confused several related technologies. What adds to the confusion is that Germans - OP used a common typo that hints at his native language - casually use "water power" ("Wasserkraft") both for hydroelectric dams ("Wasserkraftwerk") and pumped storage ("Pumpspeicherkraftwerk"). It's one of these fascinating little insights in how differe…

I'm curious, what was the typo? The grammar hinted at German, but that's all I can see.

Re: Why is hydroelectricity unfashionable?

#326

Post by jakewins »

philipkglass wrote: post #148
cwkoss wrote: post #136

Earlier quoted context omitted.

How does the energy in underground hydrogen get utilized? Is the capacity the combustive energy, or only the energy from the gas pressure?

It's burned as fuel in a gas turbine to generate electricity. The process is similar to burning natural gas in turbines, but some equipment adjustments have to be made when running on hydrogen. The Delta project is starting with a 30/70 blend of hydrogen and natural gas, gradually stepping up to 100% hydrogen. Siemens currently has turbines that can burn up to 75% hydrogen and is targeting 100% hydrogen by 2030: http…

Also used for direct industrial heat and as a feedstock!

Eg. the Hybrit project produces iron sponge with electrolyzed hydrogen. So the process becomes

> (electricity + H2O) + Fe3O4 [iron ore] => Fe + H2O

instead of the usual

> C [coke] + Fe3O4 => Fe + CO2

Re: Why is hydroelectricity unfashionable?

#327

Post by crote »

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?

In theory, yes. But I do not believe an oil field would be suitable.

Hydro relies on a pressure difference. This means you want the turbine located at the lower reservoir, which is going to be tricky with an oil well. Oil fields are not a hole filled with oil but instead are just porous rock, which greatly limits the flow rate you can achieve from a single well. Oil fields are already pressurized, so you'd actually need to put in energy to get water in there.

And of course you'd be contaminating the water with oil and gas, which makes the upper reservoir a bit of an issue.

Re: Why is hydroelectricity unfashionable?

#328

Post by crote »

exabrial wrote: post #236
01100011 wrote: post #226

Earlier quoted context omitted.

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)

Unfortunately, water has the nasty habit of dissolving salt. As the Lake Peigneur Disaster taught us, mixing the two is generally a really bad idea.

Re: Why is hydroelectricity unfashionable?

#329

Post by baxtr »

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…

Is that the case for all Hydro? Or only for specific types of Hydro applications?

I am curious to understand the different technologies. I am also asking because in the end every kind of power generation will have some effect on the ecosystems. It's always a question of trade-offs.

Re: Why is hydroelectricity unfashionable?

#330

Post by awiesenhofer »

exabrial wrote: post #204
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…

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).

No need to think only within your own state borders. Germany has lots of wind farms and not much pump storage potential as well, they just send their surplus energy south to Austria for storage. Kansas could easily do the same with Colorado - ofc they would have to build more facilities first (afaik).
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