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Why is hydroelectricity unfashionable?

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Re: Why is hydroelectricity unfashionable?

#121

Post by ethbr0 »

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…

Pumped hydro is burning energy to pump energy into a (usually artificial) reservoir.

Then, later, allowing that filled reservoir to drain through a hydroelectric plant and generate electricity.

This solves 2 major problems, compared to alternatives.

1) The scaling costs (with respect to energy storage capacity / volume) are extremely low. E.g. instead of building twice as much battery, you're just consuming additional empty space behind the dam.

2) There is no time-cost to storing energy in pumped hydro, which affords great flexibility in when it's stored and when it's extracted. E.g. stored on a bright day when the wind is blowing, extracted at night when there's no wind.

In essence, it turns spikey supply and demand patterns into more constant ones, which are cheaper and more efficient to service.

Re: Why is hydroelectricity unfashionable?

#122

Post by roamerz »

Gwypaas wrote: post #98
jhoechtl wrote: post #90

Earlier quoted context omitted.

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.

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.

Re: Why is hydroelectricity unfashionable?

#123

Post by jraph »

marcosdumay wrote: post #119
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 we aren't pumping (pun intentional) massive amounts of money into hydroelectric pumped storage Because energy storage is currently not a problem, and consequently not profitable. Unless you have some very bold organization to invest on things that today make negative marginal profit on any scale, or a government rushing into the solution of tomorrow's problem with today's money, you won't see any action. It wil…

> Because energy storage is currently not a problem

Yes it is. It's one part of the solution to fluctuations in electricity production (renewables: wind, solar) and consumption (day / night, warm / cold).

In a grid, at all time, the production has to match the consumption perfectly. You can make the frequency vary a bit to make up for fluctuations, but only so much before damaging things. Storage helps with a production higher than consumption and then with a higher consumption later.

Good storage makes grids more flexible and ideally lower the need for electricity production, and costs.

I agree with the rest of your comment though.

Re: Why is hydroelectricity unfashionable?

#124

Post by tialaramex »

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…

> 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 (perhaps to the low lake) ceases. We dig tunnels between the lakes, and we put an electric pump/ turbine in the tunnels.

When we put electricity into the pump, water from the low lake is pumped up to the high lake (until it gets too full and we stop). This stores energy. When we let the water down the pipe through the turbine instead, the same water flows from the high lake down to the low lake, giving slightly less electricity via the turbine.

Unlike the conventional hydro electric power plant this is not really producing electricity, it is storing it, hence the words "pumped storage". We can use this to move electricity in time, which otherwise has to be done very expensively with batteries.

For example, when it's windy in the middle of the night in the UK, the French and Belgians buy some of our cheap electricity, and the stored power hydro facilities in Wales and Scotland also use that electricity to pump water up to their top lakes. The next afternoon, when peak electricity usage occurs as the sun goes down and people begin cooking evening meals, the pumped storage releases the water, making electricity it can sell at peak prices. In the UK the pumped storage plants are privately owned, so they benefit financially from this arbitrage.

Re: Why is hydroelectricity unfashionable?

#125

Post by jjk166 »

whatshisface wrote: post #109
jjk166 wrote: post #107

Earlier quoted context omitted.

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…

It is a good thing then that nature has already done the excavation for us by providing high and low spots.

Yep, now we just need to excavate the reservoirs on those high and low spots, a mere 100% of the work required.

Re: Why is hydroelectricity unfashionable?

#126

Post by sidewndr46 »

BurningFrog wrote: post #111
jhoechtl wrote: post #90

Earlier quoted context omitted.

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…

I think the idea is to start pumping up water at existing hydroelectric power plants. If you do this using wind or solar power the dam becomes a giant battery you charge.

Where does this extra water come from?

Re: Why is hydroelectricity unfashionable?

#127

Post by Animats »

greedo wrote: post #64
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.

Unfortunately that rules out a lot of the US Midwest, where coal is a huge source of electricity generation.

That's the US wind belt - the Texas panhandle north to Canada, and east into Illinois.[1]

[1] https://www.kgou.org/energy/2013-09-03/oklahomas-wind-energy...

Re: Why is hydroelectricity unfashionable?

#128

Post by pclmulqdq »

cinntaile wrote: post #69
pclmulqdq wrote: post #65

Earlier quoted context omitted.

Wind and solar energy also destroy ecosystems, but we don't stop using them. Dams may be more harmful, though.

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 solar project that was planned to cover most of the land area that an endangered desert tortoise inhabits.

https://www.reuters.com/article/us-solar/exclusive-sierra-cl...

https://news.bloomberglaw.com/environment-and-energy/massive...

Aside from the large swathes of forest that have to be cut down for wind farms, birds of prey tend to fly into the blades of wind turbines. 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). In contrast, cats kill billions of birds per year, but they are common small birds, not endangered predator species.

In addition, something like 800,000 bats are killed by wind turbines.

https://wildlife.onlinelibrary.wiley.com/doi/abs/10.1002/wsb...

The solution, for solar, is obviously installations on top of human structures, like roofs and roads (but not on the road surface, which is silly). For wind, there isn't a good solution that doesn't hurt predator bird populations.

Re: Why is hydroelectricity unfashionable?

#129

Post by megaman821 »

jjk166 wrote: post #113
bryanlarsen wrote: post #96

Earlier quoted context omitted.

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.

At current battery prices of $132/kwh and oil at $88/barrel, 300 TWh of batteries per decade is actually 40% more expensive than 90 million barrels of oil per day.

Damn, we are that close. We are using expensive, high-density batteries meant for electronics and transportation for stationary storage. CATL is already claiming $40-$50/kwh for sodium ion batteries that begin production next year. In five years there will be even more grid-targeting battery solutions on the market at low price points.

Re: Why is hydroelectricity unfashionable?

#130

Post by tialaramex »

marcosdumay wrote: post #119
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 we aren't pumping (pun intentional) massive amounts of money into hydroelectric pumped storage Because energy storage is currently not a problem, and consequently not profitable. Unless you have some very bold organization to invest on things that today make negative marginal profit on any scale, or a government rushing into the solution of tomorrow's problem with today's money, you won't see any action. It wil…

> Because energy storage is currently not a problem, and consequently not profitable.

All the big pumped storage in the UK is owned by for-profit companies.

Are they making the big money from running school tours? Maybe the gift shop? I don't think so.

In the UK they can buy 1.5GWh of electricity for say £75000 on a windy Sunday night and then sell say 1.2GWh (pumped storage is maybe 80% efficient) for £200000 on Monday afternoon. That's a £125 000 profit in under a day. And this wouldn't be their best case it's just a pretty good day although there are always worse days because doing this well involves predicting weather and other factors so as to judge when to buy and sell.

They're not going to become the next Apple doing this, but it's a healthy business.

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