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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#201

Post by c7b »

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…

> Obviously hydroelectricity is massively damaging to ecosystems.

Can you elaborate? To me it always seemed like we're basically replacing a river with a lake, which doesn't seem so bad. Sure, it requires adjustment to a new equilibrium, but why is the dam lake ecosystem strictly worse than the river one?

Genuinely curious, it always seemed to me that the discussion around hydropower seemed to focus solely on what is lost from the river ecosystem, without discussing what might be gained by a lake ecosystem.

Re: Why is hydroelectricity unfashionable?

#202

Post by pydry »

lutorm wrote: post #94
theptip wrote: post #79

Earlier quoted context omitted.

Is this supported by the report though? We have yet to build most of the solar we need, and IIUC almost half of new solar is now being built with storage: > At the close of 2021, there were more than 670 GW of solar plants in the nation’s queues; 285 GW (~42%) of this capacity was proposed as a hybrid, most typically pairing PV with battery storage (PV+storage represented nearly 90% of all hybrid capacity in the queu…

My impression is that most "PV+storage" plants have storage enough to handle uneven loads and production rates on maybe hour timescales during the day. The storage required to provide overnight supply, though, is much larger, not to mention that required to handle seasonal variance in PV production. It seems hard to imagine batteries would provide that, but for that maybe the most cost-effective option is to just siz…

PV paired with wind is actually a lot more stable than either one individually because their outputs anticorrelate with each other.

A surprising amount of demand can be shifted with real time pricing, too.

Right now storage is almost irrelevant since deployed solar/wind capacity rarely reaches 100% of demand.

Re: Why is hydroelectricity unfashionable?

#203

Post by simlevesque »

enaaem wrote: post #154
rocmcd wrote: post #87

Earlier quoted context omitted.

> 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.

It also needs to be near a natural source of water, near population centres and is preferably not a pretty national park.

Doesn't need to be near population center. The majority of the energy I've used in my life comes from a dam over a thousand kilometres from where I live.

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

Re: Why is hydroelectricity unfashionable?

#204

Post by exabrial »

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).

Re: Why is hydroelectricity unfashionable?

#205

Post by buttercraft »

c7b wrote: post #201
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…

> Obviously hydroelectricity is massively damaging to ecosystems. Can you elaborate? To me it always seemed like we're basically replacing a river with a lake, which doesn't seem so bad. Sure, it requires adjustment to a new equilibrium, but why is the dam lake ecosystem strictly worse than the river one? Genuinely curious, it always seemed to me that the discussion around hydropower seemed to focus solely on what is…

For example, salmon migrate from the ocean to their spawning grounds in river beds. They have to go up over dams on special fish ladders. Most don't make it. Sockeye salmon were almost completely wiped out but are starting to bounce back. This also affects other species like bears which depend on these salmon runs before hibernation.

Re: Why is hydroelectricity unfashionable?

#206

Post by pydry »

gernb wrote: post #117
theptip wrote: post #79

Earlier quoted context omitted.

Is this supported by the report though? We have yet to build most of the solar we need, and IIUC almost half of new solar is now being built with storage: > At the close of 2021, there were more than 670 GW of solar plants in the nation’s queues; 285 GW (~42%) of this capacity was proposed as a hybrid, most typically pairing PV with battery storage (PV+storage represented nearly 90% of all hybrid capacity in the queu…

You need 2 weeks of storage. https://energytransition.org/2017/07/germanys-worse-case-sce...

This says 5 hours to get to 99%:

https://reneweconomy.com.au/a-near-100-per-cent-renewables-g...

Windgas is actually pretty suitable for that last 1%. It may be 50% efficient to produce but it's easy to store large quantities of gas for long periods for those dark/still spells.

Counterintuitively that 1% of electricity generated from windgas will among be the most expensive "green" electricity but it will probably still be cheaper than nuclear power:

https://theecologist.org/2016/feb/17/wind-power-windgas-chea...

Re: Why is hydroelectricity unfashionable?

#207

Post by _hypx »

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 lack of awareness I am talking about also applies to electrolysis. The current state of electrolyzer technology is already good enough to do the job. Future advancements will make this a no-brainer. This is similar to the rise of photovoltaics a decade (which also caught many 'experts' by surprise).

Some recent advancements:

https://www.energymonitor.ai/tech/hydrogen/toshiba-claims-hy...

https://newatlas.com/energy/hysata-efficient-hydrogen-electr...

https://energynews.biz/idaho-national-lab-and-bloom-energy-p...

Re: Why is hydroelectricity unfashionable?

#208

Post by throwawaytoilet »

WJW wrote: post #188
ssivark wrote: post #176

Earlier quoted context omitted.

I would imagine energy density to be a bigger shortcoming (gravitational acceleration times height difference) -- especially for typically accessible height differences. Eg for 500m this is something like an order of magnitude lower than chemical batteries (which are themselves presumably at least an order of magnitude lower than gasoline). This would mean that we need reservoirs to be much larger than equivalent che…

> This would mean that we need reservoirs to be much larger than equivalent chemical batteries. Yes we know. It is still cheaper on a cost-per-kwh basis than batteries, by a significant margin. > I would love to see an analysis of whether it is feasible to build enough such large scale reservoirs (and how many we would need) to store an order one fraction of the daily energy needs. (at city/country/world levels) No i…

I quite like what this startup is thinking. https://www.energybank.nz/. For offshore wind energy storage.

Re: Why is hydroelectricity unfashionable?

#209

Post by GaryNumanVevo »

Has anyone seen rail-based gravity storage projects? Obviously they aren't at the scale of hydro, but they have much less environmental impact, are relatively easy to build. ARES North America seems to have the patent rights on it, but it'd be interesting to see more large scale demonstrators.

Re: Why is hydroelectricity unfashionable?

#210

Post by pclmulqdq »

kennend3 wrote: post #189
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?

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.
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