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Re:Wind and solar are cheaper than thought, admits UK govern... by joshlemer on Thursday August 27, 2020 @02:07PM (#24296642)
I have been wondering why hydro-electric generation is often left out of discussions about renewable energy? Is it because we're currently maxing out the hydro-electric potential of the earth so there's no more gains to be had? If not, it seems like the perfect energy generation method -- it avoids the battery problem, has 0 pollution outside of initial dam construction, is perfectly safe. Three provinces in Canada are ~100% on hydro electric power.
Re:Wind and solar are cheaper than thought, admits UK govern... by vosper on Thursday August 27, 2020 @02:16PM (#24296736)
> Is it because we're currently maxing out the hydro-electric potential of the earth so there's no more gains to be had

I'm sure this is not the case, but there are often environmental and political concerns around hydro. For example, Ethiopia's new dam on the Nile river has caused tension with their neighbours, who're worried about the control it gives Ethiopia over the water supply in the river [0]

[0] https://edition.cnn.com/2020/07/21/africa/ethiopia-nile-rive...

Re:Wind and solar are cheaper than thought, admits UK govern... by madhadron on Thursday August 27, 2020 @03:06PM (#24297365)
Hydroelectric has two issues: you have to have access to appropriate rivers, and those rivers tend to be major parts of the ecosystem in their own right.

For example, Seattle is largely hydroelectric powered. The city's public utility even owns the dams, so whatever energy that isn't used in Seattle they sell to California at market rates, which makes energy conservation a profit center for them. Washington also has major mountain ranges plus the Columbia river. Kansas, on the other hand, is short on anywhere to get falling water.

On the other hand, salmon are a crucial species to the ecosystem out here. They're the primary food source of the local orca population. They're a major commercial fishery. They're one of the major sources of nutrients along the rivers going into the interior. Isotope analysis of trees along the rivers out here shows that a large amount of their growth is driven by decaying salmon.

Ross Dam and its kin that Seattle's power comes from are high enough up where we don't think there was historically much salmon run. There's a study going on now rechecking that. We've removed the Elwa River dam on the Olympic Peninsula, though. It was egregious: the requirements for salmon access were already in place when it was built, and they just ignored it and then refused to pay the fines. The Snake River dams up the Columbia are similarly problematic, and need to be removed.

This is different from, say, Switzerland, where their high dams like Grande Dixence don't have a comparable environmental effect.

Re:Wind and solar are cheaper than thought, admits UK govern... by amanaplanacanal on Thursday August 27, 2020 @02:13PM (#24296694)
I live in an area with large hydro electric usage. Unfortunately the environmental costs are pretty high for migrating fish. There is now at least some call for dam removal.
Re:Wind and solar are cheaper than thought, admits UK govern... by mullingitover on Thursday August 27, 2020 @02:39PM (#24297037)
Hydroelectric dams aren't all sunshine and roses.

> “The river was transformed from being a thriving producer of millions of fish such as shad, herring, striped bass, Atlantic salmon, sturgeon and alewives and supporting a wide cornucopia of other species ranging from otters to eagles — into a wastewater drainage system,” Jeff Crane, a dean of the College of Arts and Sciences at Saint Martin’s University, wrote in a paper published in 2009.

https://therevelator.org/edwards-dam-removal/

Re:Wind and solar are cheaper than thought, admits UK govern... by markdown on Thursday August 27, 2020 @03:09PM (#24297402)
Sounds like something else is going on. There shouldn't be much difference between the amount of water flowing into and out of a hydro dam.
Re:Wind and solar are cheaper than thought, admits UK govern... by mullingitover on Thursday August 27, 2020 @03:26PM (#24297615)
It's not about the water flow, it's that there's a physical barrier that blocks migrating fish from going between the river and the bays/estuaries/ocean.
Re:Wind and solar are cheaper than thought, admits UK govern... by markdown on Thursday August 27, 2020 @08:22PM (#24300195)
Most fish species don't migrate.
Re:Wind and solar are cheaper than thought, admits UK govern... by mullingitover on Thursday August 27, 2020 @10:01PM (#24300682)
I mean, that's true, but also every fish species listed in the above quote does, and were severely negatively impacted by the dam. They in turn feed a large amount of other wildlife.
Re:Wind and solar are cheaper than thought, admits UK govern... by markdown on Friday August 28, 2020 @01:50AM (#24301737)
I see. My mistake, I thought only salmon (from your list) migrated.
Re:Wind and solar are cheaper than thought, admits UK govern... by soperj on Thursday August 27, 2020 @02:44PM (#24297110)
>has 0 pollution outside of initial dam construction, is perfectly safe.

These are both demonstrably untrue.

1st, due to methane releases of decaying plant matter in the flood zones depending on what is flooded Hydro can actually produce over double the emissions of the worst coal plants, annually. For example the Curuá-Una dam in Pará, Brazil, has produced three-and-a-half times more emissions than an equivalent generating plant running on oil.

Based on what was flooded by the WAC Bennett dam in BC, BC likely has more GHG emmissions in their energy mix than Alberta.

And based on the size of the reservoirs(some of the largest in the world) in Quebec & that the flooded mostly boreal forest & peat land, that is also true for Quebec.

2nd, Dams breaking have caused a lot of deaths: https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

Re:Wind and solar are cheaper than thought, admits UK govern... by joshlemer on Friday August 28, 2020 @09:54AM (#24304825)
>1st, due to methane releases of decaying plant matter in the flood zones depending on what is flooded Hydro can actually produce over double the emissions of the worst coal plants, annually. For example the Curuá-Una dam in Pará, Brazil, has produced three-and-a-half times more emissions than an equivalent generating plant running on oil.

Thanks for the info, I had no idea. Is this a long term effect where reservoirs will continue to emit CO2 into the long term future, or is it just a one-off cost to transforming land into a lake? If it is just a temporary source of CO2, how long does it take for the emissions to peter out and at what point will the hydroelectric dam become even with coal in terms of emissions?

Re:Wind and solar are cheaper than thought, admits UK govern... by soperj on Friday August 28, 2020 @12:36PM (#24306893)
It's a long term effect. Trees can take over 100 years to break down in an aerobic environment. Decomposition time doubles in an anaerobic environment.
Re:Wind and solar are cheaper than thought, admits UK govern... by mcot2 on Thursday August 27, 2020 @02:12PM (#24296684)
It works extremely well in some areas but it’s not widely available in all areas. One possible solution to that is ultra high voltage dc transmission lines. Hydro Quebec is currently in the process of building one to connect Canada to the New England grid to supply very cheap hydro power to New England.
Re:Wind and solar are cheaper than thought, admits UK govern... by plorg on Thursday August 27, 2020 @02:22PM (#24296811)
Hydro has some great characteristics that contribute to carbon-free generation. MISO, which covers a huge portion of the US upper Midwest starts most of its morning ramp-up on hydro.

Aside from its environmental concerns, it will be of limited use in decarbonizing the economy because pretty much all of the useful locations have already been developed.

Re:Wind and solar are cheaper than thought, admits UK govern... by marcosdumay on Thursday August 27, 2020 @02:18PM (#24296766)
> Is it because we're currently maxing out the hydro-electric potential of the earth so there's no more gains to be had?

We are very far from the max. But the concentrated opportunities are mostly taken already. What remains is geographically dispersed, and consequently expensive.

Re:Wind and solar are cheaper than thought, admits UK govern... by surfmike on Thursday August 27, 2020 @02:12PM (#24296686)
It not only avoids the battery problem, but can be a solution to the battery problem.
Re:Wind and solar are cheaper than thought, admits UK govern... by raverbashing on Thursday August 27, 2020 @02:15PM (#24296723)
Pumping water up is very inefficient
Re:Wind and solar are cheaper than thought, admits UK govern... by gamegoblin on Thursday August 27, 2020 @02:40PM (#24297055)
Pumped-storage hydro is the most efficient large-scale energy storage mechanism. 70-80% round-trip efficiency.

https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

Re:Wind and solar are cheaper than thought, admits UK govern... by raverbashing on Thursday August 27, 2020 @03:55PM (#24297913)
I stand corrected
Re:Wind and solar are cheaper than thought, admits UK govern... by ascorbic on Thursday August 27, 2020 @02:39PM (#24297041)
Pumped hydro has an efficiency of around 80%, which is similar to lithium ion batteries. They also have massive capacity. The downside is that there aren't many places where they can be built.
Re:Wind and solar are cheaper than thought, admits UK govern... by im3w1l on Thursday August 27, 2020 @03:42PM (#24297774)
What if we dammed the Mediterranean?
Re:Wind and solar are cheaper than thought, admits UK govern... by etimberg on Thursday August 27, 2020 @08:22PM (#24300188)
Funny enough that idea was proposed in the 1920s https://en.wikipedia.org/wiki/Atlantropa
Re:Wind and solar are cheaper than thought, admits UK govern... by braythwayt on Thursday August 27, 2020 @02:42PM (#24297077)
Very.

However, nobody told the sun that, so it keeps heating up the seas, evaporating their water, and letting the resulting moisture drift until it gets pushed up into cold air by some land obstruction like a mountain range...

"Pumping" the water uphill in this manner is very inefficient, but like all legacy technologies, we're stuck with it until we can invent a replacement ;-)

Re:Wind and solar are cheaper than thought, admits UK govern... by 2YwaZHXV on Thursday August 27, 2020 @03:02PM (#24297331)
While not quite as big as other pumped storage systems this is one system that is looking to avoid the exposed area and dependence on natural reservoirs: https://heindl-energy.com/
Re:Wind and solar are cheaper than thought, admits UK govern... by ericvanular on Thursday August 27, 2020 @02:13PM (#24296698)
Basically yes, it is extremely geographically dependent