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dragontamer5788
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Re: Colorado River Water

Mon Apr 22, 2019 3:10 pm

Captain Ned wrote:
And your continual mistake is to believe that Hoover Dam can run at nameplate power 24/7/365.


Hoover Dam currently runs at roughly 6-hours a day (yearly average). There's plenty of excess capacity available for a pumped-hydro solution.

I don't think anyone is arguing for 24/7 Hoover Dam usage. At best, maybe increase it to 12-hours a day instead (doubling the power-generation of Hoover dam). Just throwing out a random number here.

Hoover Dam is huge, even getting it to run four-more hours / day on the average would result in 4 to 8GW-hr of additional electricity generation. So any hypothetical alternative project would have to be on the GW-hr scale to compare to this hypothetical project. This comes back to my fundamental point: does anyone else have a GW-hr scale solution to the problem? There's been lots of talk about "opportunity cost" and "alternative solutions", but no one (aside from Ludi) has really talked about a specific solution.

Ludi's BES proposal would be smaller, as I'm unaware of any 2+ GW-hr scale BES deployment. And I'd love to be proven wrong on this point, but my understanding of the world is that BES is smaller than GW-hr still (just barely becoming feasible for 900MW-hr or 0.9 GW-hr). There is no BES system that would deploy as cheaply as the hypothetical Hoover Dam pumped hydro project.
 
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Re: Colorado River Water

Mon Apr 22, 2019 3:21 pm

dragontamer5788 wrote:
Hoover Dam is huge, even getting it to run four-more hours / day on the average would result in 8GW-hr of additional electricity generation.

At a cost of more than 8 GWhr in power used to move the water uphill. Second Law.
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Re: Colorado River Water

Mon Apr 22, 2019 3:22 pm

dragontamer5788 wrote:
Hoover Dam currently runs at roughly 6-hours a day (yearly average).


Which, "weirdly", almost directly corresponds to how long peak demand.

Huh.

dragontamer5788 wrote:
There's plenty of excess capacity available for a pumped-hydro solution.


Solution to what problem?

Smoothing out peak demand?

What are we trying to do, again?

dragontamer5788 wrote:
I don't think anyone is arguing for 24/7 Hoover Dam usage. At best, maybe increase it to 12-hours a day instead (doubling the power-generation of Hoover dam). Just throwing out a random number here.


...and yet...

Hoover Dam is huge, even getting it to run four-more hours / day on the average would result in 8GW-hr of additional electricity generation. So any hypothetical alternative project would have to be on the GW-hr scale. This comes back to my fundamental point: does anyone else have a GW-hr scale solution to the problem? There's been lots of talk about "opportunity cost" and "alternative solutions", but no one (aside from Ludi) has really talked about a specific solution.

...you speak generically of GWh solutions as if the time of day matters not at all.

Hey! DUDE!

The entire "problem" is that California is generating umpteenth GWh at the wrong time of day so that we must "COMMAND" the Hoover Dam to "fix" it.
 
dragontamer5788
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Re: Colorado River Water

Mon Apr 22, 2019 3:27 pm

Captain Ned wrote:
dragontamer5788 wrote:
Hoover Dam is huge, even getting it to run four-more hours / day on the average would result in 8GW-hr of additional electricity generation.

At a cost of more than 8 GWhr in power used to move the water uphill. Second Law.


Yes. I'd estimate a cost of 20%. Maybe 9.6GW-hr in cost to move the water uphill, once you account for pump inefficiency, evaporation, and other losses. Lets give it a nice, round 10GW-hr cost for 8GW-hr of power-generation later. Seem fair?

The RTM market data I've posted indicates that this is still profitable, even with the 20% loss in power. The price fluctuation in SoCal's RTM energy market on 4/10/2019 was between -$3 to $87, more than enough to wipe out the 20% efficiency loss issue. In practice, the price-fluctuation will grow worse in the summer when air conditioners start to run more severely, and be less in the winter (when air conditioning is weaker). I chose the 4/10/2019 date because that was the day when I pulled statistics a few weeks ago.

EDIT: Here's the pulled statistics, once again. As long as energy prices fluctuate more than 20%, you can profit from pumped hydro.

Image
Last edited by dragontamer5788 on Mon Apr 22, 2019 3:32 pm, edited 5 times in total.
 
Glorious
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Re: Colorado River Water

Mon Apr 22, 2019 3:28 pm

Captain Ned wrote:
At a cost of more than 8 GWhr in power used to move the water uphill. Second Law.


which is why speaking of "GWh" is completely wrongheaded. It doesn't matter if stuff Lake Mead to the brim with HUGEHUGEHUGE amounts of magic water and therefore have HUGEHUGEHUGE watt hours of power behind it.

That HUGEHUGEHUGE potential can only power 2 gigawatts, and we if produce such power at the wrong time of the day---THAT WAS THE PROBLEM IN THE FIRST PLACE!
 
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Re: Colorado River Water

Mon Apr 22, 2019 3:37 pm

dragontamer5788 wrote:
Yes. I'd estimate a cost of 20%. Maybe 9.6GW-hr in cost to move the water uphill, once you account for pump inefficiency and evaporation.

The RTM market data I've posted indicates that this is still profitable, even with the 20% loss in power.


Again, how much can you get out when you actually need it with this system as opposed to how much we're getting out now?

How much we could get out if we shut it off completely at all times of non-peak demand and spend that water down to generate at peak demand times instead?

You've done no such analysis at all, nor are you even pretending to consider the enormous capital cost.

"Profitable" isn't even make-believe, you're just saying that since a differential in pricing does exist (including negative pricing at California's boondoggle of demand-decoupled peak generation), PROFIT!

Er... It's a little more ... complicated, than that? Especially since you are taking the Intra-state PUC's market with public-facing general-informational-only LOW granularity pricing summaries and just applying to that multi-state specific endeavor.

you know, just to start?
 
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Re: Colorado River Water

Mon Apr 22, 2019 3:40 pm

Er... It's a little more ... complicated, than that? Especially since you are taking the Intra-state PUC's market with public-facing LOW granularity pricing summaries and just applying to that multi-state specific endeavor.


Glorious, if you are aware of better data to prove and/or disprove my point, I'm all ears.

But yes, I'm using publicly available data because its the best data I'm aware of. Again, I'm just a programmer here, I don't do this stuff for a living. I don't have access to anything more detailed than this. If you have better data available, please post it so that we can have a better discussion.
 
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Re: Colorado River Water

Mon Apr 22, 2019 3:44 pm

alright, first off, yes, I know what ROI is, and I know that the longer the lead in time, the more pessimistic ROI projections are the ones you should look at (hope for the best, prepare for the worst).. if, in the end, all this does is costs 10 billion, and saves 11 billion, I wouldn't say do it, because it's not a high enough ROI for the risk.. but again, that's not even my argument.. you're having a long debate with two people about the same base topic, so I understand you putting a few things from the other end on me, so, that's fine.. moving on:

let's say it's worth it, the politicians all goto their proctologist to finally get that craniumdectomy (what would you call the procedure of removing your own head from your...) the water resource table gets fixed to it's the pie is split using a just above average year, (far better than what it presently is) including a single time, though tapered over a month, allocation to fill the 'to be built' lower reservoir and it gets built, ok...

(say it with me now! 'in your dreams')

at this point there is a pipe, running somewhere near, on top of, or possibly even under, the colorado river, filled with pumps to help push/pull the water up hill
and into lake mead
The end of this pipe is at either a brand new reservoir to act as the lower potential catch between the hoover dam and the davis dam, or, just use the davis dam, or, carve out a manmade lake off shooting the river for the water to sit in (yes, that will cause a lot of environmental issues, but, that's not the point I'm dealing with), or perhaps another remote, downstream, location...

so, when you say "The water is already in it." in reference to the hoover dam, I'm saying no, it's not... not in this scenario, it is in one of those locations, at the davis dam, at a new damn in line with the colorado river, or at a man made lake adjacent to the river, or other, but, it's downstream, which is what I've said several times, that's where the water is, that water will get pumped up, and then flow back through the turbines.. back downstream to the lower reservoir yet again

you want to argue the future ROI, we can, but, lets get past the 'what if it was magically created now, would it be of benefit?' stage before we talk about the likely fact that we will have fixed the colorado river water allocation, that we have stopped using fossil fuels, which because of both of those, the hoover dam will likely then be running at its full *safe* potential, and yes, at that point, you'd have to add even more infrastructure for the pump station to still do its job, but, we're not there yet

PS, in that case, we could make the pumps in the tube reversible, and all of a sudden, we have a fully self contained pump hydro station that just happens to share the upper reservoir with the hoover dam
 
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Re: Colorado River Water

Mon Apr 22, 2019 3:49 pm

dragontamer5788 wrote:
Glorious, if you are aware of better data to prove and/or disprove my point, I'm all ears.


You are the one saying that "this" is "profitable" with the sole piece of evidence being the existence of a pricing differential.

That is useless. Spending X amount on a more efficient furnace is non-economical if the amortization of that purchase via the superior efficiency is many times greater than the plausible life of the furnace itself.

In other words, saving a dollar a month on fuel costs isn't "saving" anything if it'll take half-a-century to recoup the initial cost of the furnace.

And that's actually completely ignoring the importance of the "time-value of money" and other associated concepts.

You know, just to start.

(another teaser: you're not saving as much if you suddenly move [mandatory transfer/new job etc..] to Florida even if you *BRING* the furnace: you just don't use it as much!---hence, you need to have a schedule of scenarios so you can evaluate just how seriously you can totally screw this up entirely due to changing circumstances which might entirely be outside of your control)
 
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Re: Colorado River Water

Mon Apr 22, 2019 4:04 pm

godforsaken wrote:
so, when you say "The water is already in it." in reference to the hoover dam, I'm saying no, it's not... not in this scenario, it is in one of those locations, at the davis dam, at a new damn in line with the colorado river, or at a man made lake adjacent to the river, or other, but, it's downstream, which is what I've said several times, that's where the water is, that water will get pumped up, and then flow back through the turbines.. back downstream to the lower reservoir yet again


All of the water, in any of those locations, used to be in Lake Mead.

Which you are only returning to Lake Mead.

Normally, if you don't do anything in pumped storage, that upper reservoir is completely dry.

Water doesn't start there, it isn't naturally there. Anything there was only ever there because you artificially put it there.

With Lake Mead, and your system, every ounce you put into Lake Mead was already in Lake Mead at a previous point in time. You're just putting it back, and you HAVE TO PUT BACK PRECISELY THE AMOUNT YOU LATER LET DOWN, WITHOUT FAIL.

----

That is an important consideration. It is a fundamental differentiation from other, "real" pumped storage systems.

All I am asking is that you consider that, and instead you regale me endless with the notion that, YES VIRGINIA, WE CAN RETURN WATER NOT-PRESENTLY IN LAKE MEAD BACK TO LAKE MEAD.

Yes, you can. I never said you couldn't.

I said that is fundamentally limited because we CANNOT change how much water comes out of Lake Mead over a 24 hour period, which directly limits your freedom of action here.

Again, normally, in "real" pumped storage the limit is the upper reservoir--it can't hold all that much.

Lake Mead, on the other hand, has essentially infinite capacity in relation to the system in present circumstances (though, in the early 80s, it had -no- capacity---again, something that is once-again fundamentally different). We're not concerned with how much we can store, we're concerned with that balance.

In other words, what I am telling you is that the fact that Lake Mead is the natural upper reservoir *SERIOUSLY* mutates the fundamental proposition of "pumped storage", and that other factors related to the situation constrain its productivity down to the trivial---if not futile outright.

---

I'm not interested in your self-assigned quest to demonstrate that it isn't fundamentally impossible to eek SOME benefit as a thought experiment, YES, YOU COULD.

But that DOES NOT MAKE ANY SENSE, and all of my illustrations, how reductionist and not perfectly accurate, were only intended to explain and draw out the appropriate conclusion that THIS IS NOT PLAUSIBLE.

So tilt at windmills all you like, but I'm not the one pretending to a be giant.

I mean, look at this:

godforsaken wrote:
you want to argue the future ROI, we can, but, lets get past the 'what if it was magically created now, would it be of benefit?' stage before we talk about the likely fact that we will have fixed the colorado river water allocation, that we have stopped using fossil fuels, which because of both of those, the hoover dam will likely then be running at its full *safe* potential, and yes, at that point, you'd have to add even more infrastructure for the pump station to still do its job, but, we're not there yet


I mean, do you hear yourself?

You are saying that if we fix REALITY then...

No.

There is no then. What is the point?
 
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Re: Colorado River Water

Mon Apr 22, 2019 4:14 pm

I'm done... even when I bring politics in with the idea that it was fixed, you still come back with 'we cannot do that because of politics' you have no ability to think past your own beliefs, I'm done

practically every single time we talk I have to tell you AGAIN that I'm talking about theory, practically every single time your respond with 'can't do cause politics' I stopped talking to people a long time ago, so I'm rusty, but, seriously, your inability to follow the simple premise that we're doing this all in theory before we bring the real world into the mix, to simplify and stream line things is astounding

and, do you want to know how flaky your argument is? it's all based on your premise of "All of the water, in any of those locations, used to be in Lake Mead." which, I could childishly say 'ok, bring the water in from lake eerie, and then it's no longer lake meads water', guess what, that doesn't change anything, I'm just done, I'm going to take my leave before I....
 
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Re: Colorado River Water

Mon Apr 22, 2019 4:37 pm

dragontamer5788 wrote:
#1 is "solved" not by mitigating losses per se, but by a party accepting responsibility for such losses. As long as Los Angeles is willing to keep track of those losses (which is as simple as measuring the output of the pump at Lake Mead), and as long as those losses come out of Los Angeles's water budget, then there doesn't seem to be any major political problem. It would be a problem entirely contained within Los Angeles's water rights. In effect, the project will be Los Angeles's responsibility. Cost overruns (in both $$ cost and Water costs) can be charged to LA.

Yeah, that won't happen. Southern California spends more time in drought than not and is always looking for more sources of water, to the point that the San Diego County Water Authority began purchasing water from a new desalinzation plant at Carlsbad a bit over three years ago. And part of the reason the desal plant even got done efficiently (I've heard/read) was that they used the existing cooling water intake for the Encina Power Station, which took some of the environmental roadblocks off the table.

When you're at the point where using electricity to make water is a viable option, you're not going to give up water to make electricity.
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Re: Colorado River Water

Mon Apr 22, 2019 4:47 pm

I would absolutely love to know how flaky my argument is, but your refutation of it is non-existent--i don't even understand your self-proclaimed "childish" retort, bring in lake Eerie?

What?

Please, bring in lake Eerie or any other body of water all you like, I won't be offended!

---

Again, I understand your "in theory" argument and no, I am not mentioning "politics" other than how it inevitably informs the technical requirement of water neutrality.

Yes, you could pump "more" water back up and then just let it down again later--the point is that "more" has to directly equate with currently unused peak capacity(for want of water) that cannot be met by just not running water through at non-peak.

My contention (and first approximation reductionist illustration) is that this actually approaches zero.

That is, broadly speaking, there is no point in pumping at all because all of the necessary water within the 24 hour constraint is "already there"--the amount of water necessary to reach maximum at peak is expended during non-peak.

In order for this not to be true (as an approximate method), hoover dam must approach idle during peak and water dispensation during non-peak must approach zero.

I already know that generally speaking neither of those contentions is true, certainly not the former and the latter is additionally extremely seasonal.

Thus my conclusion, which follows that approach: do nothing. I think it is sensible.

If it isn't, please feel free to explain how. You don't need to waste time with how thick and obstinate I am, just show me (and everyone else) where I went wrong.
 
dragontamer5788
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Re: Colorado River Water

Mon Apr 22, 2019 4:55 pm

ludi wrote:
dragontamer5788 wrote:
#1 is "solved" not by mitigating losses per se, but by a party accepting responsibility for such losses. As long as Los Angeles is willing to keep track of those losses (which is as simple as measuring the output of the pump at Lake Mead), and as long as those losses come out of Los Angeles's water budget, then there doesn't seem to be any major political problem. It would be a problem entirely contained within Los Angeles's water rights. In effect, the project will be Los Angeles's responsibility. Cost overruns (in both $$ cost and Water costs) can be charged to LA.

Yeah, that won't happen. Southern California spends more time in drought than not and is always looking for more sources of water, to the point that the San Diego County Water Authority began purchasing water from a new desalinzation plant at Carlsbad a bit over three years ago. And part of the reason the desal plant even got done efficiently (I've heard/read) was that they used the existing cooling water intake for the Encina Power Station, which took some of the environmental roadblocks off the table.

When you're at the point where using electricity to make water is a viable option, you're not going to give up water to make electricity.


I think you're underestimating the amount of solar panels that will be deployed in the near future. Solar panels are very, very cheap now... and will continue to be cheap in the foreseeable future. The issue is just finding a use of all of that electricity (because the sun doesn't always shine when electricity is needed). If the desalination plant is making water during times of excess power, then it wouldn't be a big deal. (I know Germany uses its excess power to smelt aluminum, another high-electric cost industry).

Do you have any information on the Desalination plant at Carlsbad? My bet is that its planning to use the excess power of modern solar panels to function. All it'd have to do is turn off during peak-electric demand hours to be useful. (Note: Desalination plants probably would have a required water output, but they can probably participate in the day-ahead market to pick the lowest cost 18-hours each day to run on a daily basis, or whatever % time their managers decide to run the plant. There's no need to run the plant 24-hours a day).

Furthermore, the nominal "use" of water in pumped-hydro is zero. That doesn't exist in reality because of inefficiencies like evaporation, but the amount of water lost is miniscule compared to the amount of electricity time-arbitraged. And once again, evaporative losses are primarily from Lake Mead itself, the largest surface area in the region. Any evaporative losses from a new resovoir would be miniscule compared to the losses already going on in the system right now.
 
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Re: Colorado River Water

Mon Apr 22, 2019 5:05 pm

dragontamer5788 wrote:
I think you're underestimating the amount of solar panels that will be deployed in the near future


Whereas with much better reason I think you are underestimating ludi.

dragontamer5788 wrote:
If the desalination plant is making water during times of excess power, then it wouldn't be a big deal.


It is a pretty big deal if you can only run them for 6 hours a day.

(I know Germany uses its excess power to smelt aluminum, another high-electric cost industry).

Haha I work in the metals industry with arc furnaces dude, we run them 24/7/365 except when we have to maintain stuff.

That is how it is in capital intensive industry, ok?

Sure is it nice to not pay more during peak or god forbid be ordered to turn 'em off, but that's not really the same thing. We're running brother, or I am at work figuring out why we're not with the plant manager sitting on my lap.
 
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Re: Colorado River Water

Mon Apr 22, 2019 5:11 pm

Glorious wrote:
Haha I work in the metals industry with arc furnaces dude, we run them 24/7/365 except when we have to maintain stuff.

That is how it is in capital intensive industry, ok?

Sure is it nice to not pay more during peak or god forbid be ordered to turn 'em off, but that's not really the same thing. We're running brother, or I am at work figuring out why we're not with the plant manager sitting on my lap.


Are you calling me out on this?

Google: Trimet Aluminum Enpots virtual battery.

They have a flexible demand of +/- 25% on the grid, to respond to the daily fluctuations of the energy grid. Perhaps I described it incorrectly initially, its not so much that it "turns off", as much as it "responds to demand". But the concept remains the same. The German plant is designed to have constant output, despite fluctuating its energy usage throughout the day. EDIT: Allegedly, there's another program that a lot of Germany's aluminum smelters follow where they turn off entirely if the grid is very overloaded. But this "virtual battery" is independent of that.

I'm not in that industry, but I do keep up with news because I'm interested in the subject. Trust me, I'm not making crap up here. In either case, I'd expect modern plants to be better and better built towards "flexible" electricity usage.

----------

EDIT: I think I've left the core argument with Ludi. To bring it back: I would expect a modern desalination plant to be built with some degree of "on demand" flexibility, similar to the "Enpots Virtual Battery" for aluminum smelting. I don't know the technologies available, so maybe it won't be +/-25%, but it would likely be responsive to some degree. As long as its responsive enough to draw power in times of excess energy, and to reduce its power-usage during peak demand... it would actually be beneficial to "spend water to make electricity", so to speak.
Last edited by dragontamer5788 on Mon Apr 22, 2019 5:32 pm, edited 1 time in total.
 
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Re: Colorado River Water

Mon Apr 22, 2019 5:31 pm

dragontamer5788 wrote:
Are you calling me out on this?


What is with your obsession with "calling out"?

dragontamer5788 wrote:
Trust me, I'm not making crap up here.


I mean, you're just regurgitating an article you just read with no other content or understanding.

I mean, dude, I already mentioned this:

dragontamer5788 wrote:
EDIT: Allegedly, there's another program that a lot of Germany's aluminum smelters follow where they turn off entirely if the grid is very overloaded.


Yes, that's called "curtailment" and it's kind of universal in heavy industry.

----

So, uh, no? I don't think you're "making this up", I think you're just googling whatever and then reciting what you found.

Usually while saying I don't understand anything.

It's surreal.
 
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Re: Colorado River Water

Mon Apr 22, 2019 5:33 pm

Glorious wrote:
Yes, that's called "curtailment" and it's kind of universal in heavy industry.


Cool. Well thanks for the vocab lesson then. I fully admit that I'm not in the heavy metals industry.
 
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Re: Colorado River Water

Mon Apr 22, 2019 7:47 pm

Captain Ned wrote:
Is this the appropriate time to remind you of the Second Law of Thermodynamics?

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Re: Colorado River Water

Mon Apr 22, 2019 8:55 pm

Having grown up around very large hydroelectric dams and working on the rivers for the first 20 or so years of my working life, there are quite a few things that are being missed here. You need a river system with surplus water, like the Columbia/Snake River system. The Colorado is all done up and never had enough potential energy to do what is being suggested. There just aren't enough rivers flowing into it, and the climate is so much warmer and drier that evaporation takes a sizable chunk out of it's potential.

1. You cannot mess with the flow of the water. There are several reasons:
a. Reducing the flow of water downstream of a dam causes huge issues with silt buildup. It clogs up things further downstream. There is a bare minimum amount of water and a bare minimum of force of that water that must travel downstream to mitigate this. "Returning" or forced pumping is going to really mess with this. That silt also has a very negative effect on animals downstream, primarily fish. This will come into direct conflict with the Endangered Species Act.
b. Reducing the flow of water downstream of a dam also causes the water to warm. Moving water cools. Stagnating water warms. This causes even more evaporation, and causes for water-born diseases to have a stronger foothold. It also kills fish and other aquatic wildlife.
c. Reducing the flow of water downstream of a dam also reduces the ability for the river to purify the water. Flowing water allows for sediment to work its way out of the water and into the riverbed. This presents problems for drinking water.

2. Using excess energy to pump water back up to the high water side..... it is a nice idea. But incredibly difficult. How much volume? Because negligible is all that can really be done. Pumping a significant volume of water up the 700 or so feet up is going to require a serious amount of power. And noise. The Hoover Dam has some really weird spillways. The Arizona Spillway alone is a 50' diameter. I think the penstocks are something like 13' diameter, and there are 4 of them. Then there are the 6 - 8 1/2' outlet pipes that let water down the weird spillway. I don't remember that one. So how large of a pipe is going to be used? And then piped nearly straight up 700'? And then will this be an open pipe return? Because if it is, you have to account for the massive amount of evaporation and that has to come out of the water allotment. So, let's just say that we are going to use something the size of one of the penstocks. 1 13' pipe. We are looking at a pipe volume of 92,912 cubic feet or 695,030 gallons. A cubic foot of water weighs 62.43 pounds. This is 27 tons of water. And at what sort of pressure? This is going to be a huge pump. And it is going to draw a whole bunch of power.

3. Here is an even more weird one for you. Back in 2010, they had a huge storm in the region. A half a Billion gallons were dumped into Lake Mead over a week. It raised the water level by 1/5th of an inch. To raise the water level of Lake Mead by 1/5th of an inch, will need push 92,912 cubic feet of water out 7.5 times.

4. There is not a water rights-holder out there willing to give up 695,030 cubic feet of water. And that is just to add 1/5th of an inch. There is no return on this investment.

And this is to save energy? This sounds great for a nice little dam somewhere in the northeast. On the Columbia and Snake rivers, we have dams every 20 miles. And it isn't even feasible there. It would kill off the salmon who need a strong current both to encourage spawning and to keep the fertilized eggs from being covered by silt. The Colorado is a mess. Not enough water for it.
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Re: Colorado River Water

Fri Apr 26, 2019 9:59 pm

I've been following and I've read every post in this thread.

@JAE (replying to Ned): LOL

@Aranarth - thank you for the sensible, fact-filled, level-headed posts. You touched on something that occurred to me a couple of pages back. Why go back upriver? If pumped hydro was deemed necessary and a project was actually agreed upon, why not just build the battery reservoir on the shores (well, a high shore) of Lake Mead? If it's critical to generate more electricity, install some new turbines along with the pumps, or the fancy reversible ones, and just leave Hoover Dam out of this project?

I'm not suggesting doing this or that it's a good idea, and I'm aware that even if it was a good idea, it wouldn't just happen simply because of its goodness. Evaporation alone is probably a good enough reason not to, along with plenty more. However, this method does seem a bit more traditional relating to pumped hydro technical feasibility than the "water through the same dam twice" method. I'm pretty much in the camp of "this will never happen on that Colorado River."
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JustAnEngineer
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Re: Colorado River Water

Fri Apr 26, 2019 11:02 pm

Hoover Dam is attractive for this proposed pumped hydro energy storage project because it has under-utilized assets (existing elevated storage reservoir and generating capacity). Re-using those assets as part of the proposed energy storage loop could make the overall project more financially justifiable, since one would need to construct just a lower reservoir and return pumping system rather than a complete green-field development. Sometimes, it's cheaper to go build something completely new, but frequently, projects that leverage existing assets to do more can be a more efficient use of capital than a green-field project.

For all of the posters hung up on the idea that ignorant politicans would block recycling of water, consider that having an existing elevated reservoir and generating station is a big plus from an environmental permitting standpoint compared to green-field development, which might be tied up with legal rigamarole for a decade or more. As an engineer, I usually consider squandering three quarters of your total project investment to pay lawyers instead of actually using that money to build something to be inefficient.
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Shobai
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Re: Colorado River Water

Sat Apr 27, 2019 4:37 am

JustAnEngineer wrote:
As an engineer, I usually consider squandering three quarters of your total project investment to pay lawyers instead of actually using that money to build something to be inefficient.


Well, I'll bite: as an engineer, can you provide an example of a time where you didn't consider squandering three quarters of your total project investment to pay lawyers instead of actually using that money to build something to be inefficient?
 
JustAnEngineer
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Re: Colorado River Water

Sat Apr 27, 2019 4:59 am

Shobai wrote:
Provide an example of a time where you didn't consider squandering three quarters of your total project investment to pay lawyers instead of actually using that money to build something to be inefficient.
When the due diligence process found something in a proposed merger that said "run away!" before the transaction went through. Bullet successfully dodged.
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