4 ms·

I wonder why existing hydro isn't utilized to it's potential. For instance, the Grand Coulee Dam has the highest capacity of any power station in the US of almo

by jp191919 8mo ago

I wonder why existing hydro isn't utilized to it's potential. For instance, the Grand Coulee Dam has the highest capacity of any power station in the US of almost 7 MW but usually puts out about a third of that.

ceejayoz 8mo ago
It turns out that "releasing immense amounts of water downstream" can have side effects.
- ikawe 8mo ago
  What do you think is happening to the water not being utilized in the production of power? I assumed it's still being run downstream, just not through the power producing turbines. I'd expect there's not a big effect on the ultimate amount of water being released downstream either way.
  - ceejayoz 8mo ago
    They let the reservoir fill up for when the power and/or drinking water is needed later. The max is like a car engine’s redline. That the car can hit it doesn’t mean you should at all times.
richardubright 8mo ago
Looking at the data for lake that goes through the dam, it seems like they keep it at the same level. So it probably CAN make 7MW with more flow, but generally only flows at a state that puts out 2.
- jp191919 8mo ago
  I looked into this more, and there is quite a bit of seasonal variability to contend with as well.
  - shagie 8mo ago
    https://www.forbes.com/sites/jonbruner/2011/10/20/the-high-stakes-math-behind-the-wests-greatest-river/ https://www.forbes.com/sites/jonbruner/2011/10/20/the-high-s... has some interesting data on the Columbia River and its dams. From that https://youtu.be/jvnaiHFT6nQ https://youtu.be/jvnaiHFT6nQ is a visualization of the water releases for the river to allow the water to get to the right dam for the anticipated power use.
- lazide 8mo ago
  There is no way it’s max is 7MW. They likely meant 7GW. 7MW is the amount of power you can get from a couple of diesel gensets, waaaay smaller than even a small power plant [https://www.cat.com/en_US/products/new/power-systems/electric-power/diesel-generator-sets/1000028938.html https://www.cat.com/en_US/products/new/power-systems/electri...]
  - jp191919 8mo ago
    Yes, 7GW. I can't edit original comment.
SigmundA 8mo ago
https://en.wikipedia.org/wiki/Capacity_factor https://en.wikipedia.org/wiki/Capacity_factor
bob1029 8mo ago
Vogtle is probably producing the most electricity out of any generating plant in the US once you consider capacity factor.
- bryanlarsen 8mo ago
  Vogtle is also the most expensive electricity in the world, the only electricity costing more than $10,000 per kW.
  - jp191919 8mo ago
    And on the other end of the spectrum, grand coulee would be ~$1,500/kW in todays dollars.
    - ceejayoz 8mo ago
      Those are very different metrics. edit: Parent got edited; it was talking about $0.02/kwh initially.
  - bryanlarsen 8mo ago
    Vogtle won't stay the most expensive. My idiotic government (Ontario, Canada) is committing to building a new nuclear plant. $400 billion for 10GW, and that's before the inevitable delays and cost overruns. Maybe we'll break the $100,000 per kW mark!
dec0dedab0de 8mo ago
Niagra falls doesn't run at full capacity because it takes away from the attraction of the falls themselves, and tourism is important there. They turn up capacity after hours, and the falls slow down.
- iracigt 8mo ago
  Not only that, they use the gravitational potential of the falls to store massive amounts of energy when there's a surplus. Way cheaper to hold or even pump the water back up to the reservoir at the top than build lithium batteries. So yeah, as a local, can confirm they turn Niagara Falls (partially) off at night. Thanks to the Falls and several nuclear plants on Lake Ontario, Upstate NY and Southern Ontario have some of the lowest carbon electricity in the countries. Quebec is even better with basically all of their power coming from hydro. See also https://en.wikipedia.org/wiki/International_Control_Dam https://en.wikipedia.org/wiki/International_Control_Dam
  - kevin_thibedeau 8mo ago
    The Ginna nuclear plant is the second oldest in the US and is on a license extension that expires in three years. There is nothing to replace that capacity. Western NY is going to see significant price hikes because of this short-sightedness.
716dpl 8mo ago
Limited water resource. In recent drought years, gas-fired power plants in California had to make up for reduced hydro generation.
ViewTrick1002 8mo ago
They are used as dispatchable sources. Capture value by being able to provide enormous amounts of power when needed compared to the watershed flow.
willturman 8mo ago
Lake Powell behind Glen Canyon Dam is currently at 23.6% of capacity. Lake Mead behind Hoover Dam is currently at 29.7% of capacity. Given the current state of the Upper Colorado River basin snow pack, there is a not-insignificant chance that Lake Powell will recede below a minimum power generating level by the end of this year for the first time ever.

ceejayoz 8mo ago

It turns out that "releasing immense amounts of water downstream" can have side effects.

ikawe 8mo ago
What do you think is happening to the water not being utilized in the production of power? I assumed it's still being run downstream, just not through the power producing turbines. I'd expect there's not a big effect on the ultimate amount of water being released downstream either way.
- ceejayoz 8mo ago
  They let the reservoir fill up for when the power and/or drinking water is needed later. The max is like a car engine’s redline. That the car can hit it doesn’t mean you should at all times.

richardubright 8mo ago

Looking at the data for lake that goes through the dam, it seems like they keep it at the same level. So it probably CAN make 7MW with more flow, but generally only flows at a state that puts out 2.

jp191919 8mo ago
I looked into this more, and there is quite a bit of seasonal variability to contend with as well.
- shagie 8mo ago
  https://www.forbes.com/sites/jonbruner/2011/10/20/the-high-stakes-math-behind-the-wests-greatest-river/ https://www.forbes.com/sites/jonbruner/2011/10/20/the-high-s... has some interesting data on the Columbia River and its dams. From that https://youtu.be/jvnaiHFT6nQ https://youtu.be/jvnaiHFT6nQ is a visualization of the water releases for the river to allow the water to get to the right dam for the anticipated power use.
lazide 8mo ago
There is no way it’s max is 7MW. They likely meant 7GW. 7MW is the amount of power you can get from a couple of diesel gensets, waaaay smaller than even a small power plant [https://www.cat.com/en_US/products/new/power-systems/electric-power/diesel-generator-sets/1000028938.html https://www.cat.com/en_US/products/new/power-systems/electri...]
- jp191919 8mo ago
  Yes, 7GW. I can't edit original comment.

SigmundA 8mo ago

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

bob1029 8mo ago

Vogtle is probably producing the most electricity out of any generating plant in the US once you consider capacity factor.

bryanlarsen 8mo ago
Vogtle is also the most expensive electricity in the world, the only electricity costing more than $10,000 per kW.
- jp191919 8mo ago
  And on the other end of the spectrum, grand coulee would be ~$1,500/kW in todays dollars.
  - ceejayoz 8mo ago
    Those are very different metrics. edit: Parent got edited; it was talking about $0.02/kwh initially.
- bryanlarsen 8mo ago
  Vogtle won't stay the most expensive. My idiotic government (Ontario, Canada) is committing to building a new nuclear plant. $400 billion for 10GW, and that's before the inevitable delays and cost overruns. Maybe we'll break the $100,000 per kW mark!

dec0dedab0de 8mo ago

Niagra falls doesn't run at full capacity because it takes away from the attraction of the falls themselves, and tourism is important there. They turn up capacity after hours, and the falls slow down.

iracigt 8mo ago
Not only that, they use the gravitational potential of the falls to store massive amounts of energy when there's a surplus. Way cheaper to hold or even pump the water back up to the reservoir at the top than build lithium batteries. So yeah, as a local, can confirm they turn Niagara Falls (partially) off at night. Thanks to the Falls and several nuclear plants on Lake Ontario, Upstate NY and Southern Ontario have some of the lowest carbon electricity in the countries. Quebec is even better with basically all of their power coming from hydro. See also https://en.wikipedia.org/wiki/International_Control_Dam https://en.wikipedia.org/wiki/International_Control_Dam
- kevin_thibedeau 8mo ago
  The Ginna nuclear plant is the second oldest in the US and is on a license extension that expires in three years. There is nothing to replace that capacity. Western NY is going to see significant price hikes because of this short-sightedness.

716dpl 8mo ago

Limited water resource. In recent drought years, gas-fired power plants in California had to make up for reduced hydro generation.

ViewTrick1002 8mo ago

They are used as dispatchable sources. Capture value by being able to provide enormous amounts of power when needed compared to the watershed flow.

willturman 8mo ago

Lake Powell behind Glen Canyon Dam is currently at 23.6% of capacity. Lake Mead behind Hoover Dam is currently at 29.7% of capacity. Given the current state of the Upper Colorado River basin snow pack, there is a not-insignificant chance that Lake Powell will recede below a minimum power generating level by the end of this year for the first time ever.