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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#241

Post by sien »

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.

Fun fact, the Australian Green Party was born protesting renewable electricity. They stopped the development of the Franklin Dam in Tasmania.

"In the late 1970s and 1980s, a public campaign to prevent the construction of the Franklin Dam in Tasmania saw environmentalist and activist Norm Sanders elected to the Tasmanian House of Assembly as an Australian Democrat. Brown, then director of the Wilderness Society, contested the election as an independent, but failed to win a seat.[3]"

From

https://en.wikipedia.org/wiki/History_of_the_Australian_Gree...

The founder of the Green, Bob Brown, now opposes wind farms in Tasmania.

https://en.wikipedia.org/wiki/Bob_Brown#Opposition_to_a_Tasm...

Re: Why is hydroelectricity unfashionable?

#242

Post by Retric »

mindslight wrote: post #224
Retric wrote: post #171

Earlier quoted context omitted.

Ideally you don’t build a dam. Niagara Falls sits between Lake Erie into Lake Ontario. Which is the perfect location to use pumped hydro because all you need to build is a pipe between them and put a turbine inside the pipe. If you have excess energy pump water up from Lake Ontario to Lake Erie, and when you need power run that in reverse to generate electricity. Move enough water and the water level on each lake wil…

The scenario you've described still begs the question though. It seems the only difference between traditional hydroelectricity and pumped storage is how much you disrupt the natural flow from Lake Erie to Lake Ontario. The hard limit is when the Niagara Falls run dry. Anything more than that is basically spending electricity to create a treadmill for fish, which may be the environmentally responsible thing but we sh…

We let stuff migrate upriver years ago when they added a lock system back in 1829. At this point any environmental harm from connecting these lakes has already happened generations ago well before we where born. https://en.wikipedia.org/wiki/Welland_Canal

Anyway, the amount of water flowing over Niagara Falls is currently regulated hourly by treaty with excess flows above that level used to generate hydroelectricity. 100,000 cubic feet per second (2,800 m3/s) of water flowing over the falls, and during the night and off-tourist season there must be 50,000 cubic feet per second (1,400 m3/s) of water flowing over the falls. That excess is generally 50-70% of the rivers total, making the falls arguably just a really large and extremely expensive water feature used to attract tourism. https://en.wikipedia.org/wiki/List_of_Niagara_Falls_hydroele...

Adding a separate pumped hydro system really can be treated as an independent entity because we don’t just control the falls we can even turn it off when needed. https://www.dailymail.co.uk/news/article-1338793/Niagara-Fal...

Re: Why is hydroelectricity unfashionable?

#243

Post by pfdietz »

WJW wrote: post #151
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?

No it's mostly the chemical energy in the stored hydrogen, pressure is only a small part of it (though they might insert some expander turbine somewhere in there). Pretty similar to how you'd rate a natural gas storage facility.

It should be noted that the energy stored in the pressure of gas is zero. All the energy of an ideal gas is the kinetic energy (and rotational/vibrational energy) of its molecules, which is thermal energy. Internal energy of an ideal gas is independent of pressure.

What compressed gas storage does is (aside from combustion energy of a fuel gas) to provide not a store of energy, but a store of reduced entropy, enabling otherwise unusable amounts of heat to be converted to work.

Re: Why is hydroelectricity unfashionable?

#244

Post by pfdietz »

speakfreely wrote: post #196
_hypx wrote: post #173

Earlier quoted context omitted.

The recent appearance of hydrogen energy storage has basically refuted this argument. We can now store all of the renewable energy we want. The only problem is the lack of awareness among environmentalists and engineers.

My limited understanding was that the electrolysis tech is not yet efficient enough at scale to make this feasible. Do you have links where I could read more about the cutting edge in hydrogen production? This is a very fascinating potential tool for solving the "we don't have enough batteries" problem with renewables.

The problem with electrolysis was not its efficiency, the problem was capital cost of the electrolysers (so they could be paired effectively with intermittently overproducing renewables.) Efficiency was more of the concern when it was imagined expensive nuclear power would be driving electrolysers 24/7.

Re: Why is hydroelectricity unfashionable?

#245

Post by pfdietz »

pydry wrote: post #200
_hypx wrote: post #173

Earlier quoted context omitted.

The recent appearance of hydrogen energy storage has basically refuted this argument. We can now store all of the renewable energy we want. The only problem is the lack of awareness among environmentalists and engineers.

Hydrogen leaks like crazy and corrodes storage cannisters. It isnt especially practical.

The world produces and uses 700 cubic kilometers (at STP) of hydrogen annually. Hydrogen has been used on a mass scale industrially since the 1800s. The US has over 1000 miles of hydrogen pipelines.

There are obviously off the shelf components for dealing with hydrogen. This is not some hand wringing unsolved problem.

Re: Why is hydroelectricity unfashionable?

#246

Post by pfdietz »

sidewndr46 wrote: post #166
BurningFrog wrote: post #159

Earlier quoted context omitted.

Hydro power work by water flowing down turbines from a higher body of water to a lower. So you can typically pump the lower water back up, using wind or solar power.

Wouldn't this mean the downstream would have no water flowing through it?

Pumped hydro can be built entirely off rivers. There's a plan to put a reservoir for one on top of a mesa in the desert in Arizona, for example.

Re: Why is hydroelectricity unfashionable?

#247

Post by pfdietz »

plorg wrote: post #54
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…

When I was in school for power systems planning the the accepted notion was that pumped hydro storage is cool and great, but like hydropower, it is extremely geographically dependent, and we have basically developed all of the places where it would work (at least in the US), or at least, by order of magnitude, there are not enough remaining untapped hydro-related resources to make a dent in projected storage demand.…

It's geographically dependent if built on rivers. Beyond rivers the possibilities expand enormously.

Re: Why is hydroelectricity unfashionable?

#248

Post by pfdietz »

rocmcd wrote: post #87
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.

> All pumped storage requires is a big high spot and a big low spot I think that's what the GP meant by "extremely geographically dependent." Finding a 1,000 ft height difference (using the Gordon Butte Project as an example) between reservoirs will be really challenging in huge swaths of the United States and elsewhere.

There are many possibilities globally. 1000 feet is not needed.

https://re100.eng.anu.edu.au/global/

Re: Why is hydroelectricity unfashionable?

#249

Post by StanislavPetrov »

>They are blamed for displacing populations, disrupting the flow of sediments and the migration of fish, destroying natural habitat and biodiversity, degrading water quality, and for the decay of submerged vegetation and the consequent release of methane, a greenhouse gas. There is thus no longer a place for Big Hydro in the pantheon of electric greenery.

Dams are blamed for displacing populations, disrupting the flow of sediments and the migration of fish, destroying natural habitat and biodiversity, degrading water quality, and for the decay of submerged vegetation and the consequent release of methane, a greenhouse gas because that is exactly what they do.

>Instead, that pure status is now reserved above all for wind and solar. This ennoblement is strange, given that wind projects require enormous quantities of embodied energy in the form of steel for towers, plastics for blades, and concrete for foundations.

What does he think they build dams out of?

Re: Why is hydroelectricity unfashionable?

#250

Post by pfdietz »

hypertele-Xii wrote: post #134
jhoechtl wrote: post #110

Earlier quoted context omitted.

Germany is anecdotally facing an Energy crisis Nuclear power:no. Wind energy: off shore out of sight yes, but not on my mountain. Russian gas: no (more). Coal instead? No! So eveyone will install mini PV systems and become self-sufficient? First this wont work during the cold season and how incredible inneficient is this going to be? I think we must stop to outsource providing cheap energy to poor countries and tap o…

There is no lithium to mine around your corner. Half of all known deposits on Earth are in Bolivia and Argentina.

Is France around the corner from Germany? Because France has lithium.

https://www.euronews.com/green/2022/10/24/frances-massive-ne...

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