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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#91

Post by karamanolev »

rr808 wrote: post #76
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…

Agreed we need hydroelectric pumped storage - what is a typical efficiency number for that? I'd think its super inefficient, but not sure what the numbers should be.

> The round-trip energy efficiency of PSH varies between 70%–80%, with some sources claiming up to 87%.

For me, that sounds like quite good, given the capacity possibilities. We can always build tiered storage, with smaller, but more efficient tiers (e.g. batteries) used first and PSH when that's filled up or exhausted.

Re: Why is hydroelectricity unfashionable?

#92

Post by jandrese »

dottedmag wrote: post #47
insane_dreamer wrote: post #21

Earlier quoted context omitted.

Is this indeed the case, even for smaller, localized dams? Would be interesting to see a comprehensive study on this (if one has been done).

Looks like I was wrong! This report puts current usage to 20%: https://web.archive.org/web/20170329132409/http://www.iea.or...

That report is interesting, but incomplete. Certainly there are diminishing returns on developing that last 80%. It's entirely possible that many of the locations are outright uneconomical to develop, possibly because they are hundreds of miles from the nearest significant civilization and would require enormous high voltage lines before they could be developed. Or maybe upstream of the location is a lot of people who would need to move first.

Re: Why is hydroelectricity unfashionable?

#93

Post by jandrese »

Kukumber wrote: post #39

Because lobby The day you come up with infinite and free aboundant energy will be the day you put to bankruptcy both the US, the Middle East and Russia, and they don't want that But it's in the plan anyways, we are getting the taste of it right now, globally Bonus: https://www.youtube.com/watch?v=2WeoeJyJmN4&t=455s

That sounds just like hand wringing over killing off the buggy whip industry. Markets are disrupted sometimes, people cope.

Re: Why is hydroelectricity unfashionable?

#94

Post by lutorm »

theptip wrote: post #79
idiotsecant wrote: post #53

Earlier quoted context omitted.

Too little, too late unfortunately. The amount of storage available from these projects is tiny and even though it's accelerating it's not accelerating at nearly the level required for the physics of a primary renewable grid to work. Chemical storage of energy is expensive and requires a long supply chain. It's huge that the costs are trending in a favorable direction and maybe eventually we can do all our load balan…

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 size the PV capacity for the worst-case season.

Given the evolution in PV cost, maybe it will be cheaper to size PV production to worst-case days rather than size it for an average day+storage? You'd still need sufficient storage for overnight consumption, obviously.

Re: Why is hydroelectricity unfashionable?

#95

Post by [deleted] »

burkaman wrote: post #72
idiotsecant wrote: post #31

Earlier quoted context omitted.

for some definition of the word 'best' - we have plenty of places that would be perfectly suitable other than all the pesky people it would displace. If we really cared about carbon-free energy that would be a solvable problem.

But the only reason we care about carbon-free energy is because of the pesky people. If displacing people isn't a big deal, then climate change isn't a problem and we don't need to care about carbon-free energy at all. We'd just move populations as the climate changes.

[deleted]

Re: Why is hydroelectricity unfashionable?

#96

Post by bryanlarsen »

idiotsecant wrote: post #63
bryanlarsen wrote: post #57

Earlier quoted context omitted.

We certainly can use solar, wind & batteries to eliminate fossil fuels from our electricity system. Estimates are that we'd need about 300TWh of batteries, which is on the edge of feasible. Pumped storage would be a lot cheaper, though.

Oh great, only 300TWH of batteries! Let's put in the P.O.! Who is supplying those, again?

300TWh of batteries per decade is a lot easier than 90 million barrels of oil per day yet somehow we manage to do the latter.

Re: Why is hydroelectricity unfashionable?

#97

Post by jhoechtl »

api wrote: post #82
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've wondered for a while if we couldn't build a pipeline between the ocean and the Salton Sea in SoCal and store quite a bit of energy that way. The Salton Sea is already kind of a wasteland so at least use it for something.

What is the difference in meters? If not much, the effort of building will not be counterweighted by the energy storage capacity.

AFAIK salton sea is pretty much at sea level?

Re: Why is hydroelectricity unfashionable?

#98

Post by Gwypaas »

jhoechtl wrote: post #90
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…

Forgive me my lack of understanding of the englisch language, but I do not understand the distinction you make. Hydroelectricity: Is this power you obtain by placing turbines behind a huge concrete wall of a large river? If so, how is the scenario of building a large concrete dam in the mountains where water is pumped up a hill to covert it into kinetic energy any more better? I understand that hydroelectricity is us…

Because you're not disrupting a river's flow and natural ecosystem, you only utilize the watershed some more during the initial filling period. After that, it's a closed system separate from the river ecosystem where only evaporation causes leakage.

Re: Why is hydroelectricity unfashionable?

#99

Post by Giorgi »

Kukumber wrote: post #39

Because lobby The day you come up with infinite and free aboundant energy will be the day you put to bankruptcy both the US, the Middle East and Russia, and they don't want that But it's in the plan anyways, we are getting the taste of it right now, globally Bonus: https://www.youtube.com/watch?v=2WeoeJyJmN4&t=455s

Yeah, US is not oil-export dependent in any way.

Re: Why is hydroelectricity unfashionable?

#100

Post by rr808 »

karamanolev wrote: post #91
rr808 wrote: post #76

Earlier quoted context omitted.

Agreed we need hydroelectric pumped storage - what is a typical efficiency number for that? I'd think its super inefficient, but not sure what the numbers should be.

> The round-trip energy efficiency of PSH varies between 70%–80%, with some sources claiming up to 87%. For me, that sounds like quite good, given the capacity possibilities. We can always build tiered storage, with smaller, but more efficient tiers (e.g. batteries) used first and PSH when that's filled up or exhausted.

Wow I actually was expecting more like 10-20%.
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