H.R.1588 - To modernize the hydropower licensing process and to promote next generation hydropower projects

[svetz]

H.R.1588 - no text yet, but you can sign up for alerts

Possibly related to this from Mr. Westerman:

Why not put hydroelectric plants on existing dams? We don't have to build new dams. We can add 12,000 megawatts of clean, carbon-free hydropower on existing dams.

 

[memilanuk]

Why not put hydroelectric plants on existing dams? We don't have to build new dams. We can add 12,000 megawatts of clean, carbon-free hydropower on existing dams.

Okay... I'm curious how they see that working out - specifically. I work in the industry, as it happens.

 

[svetz]

Sounds like it's too clear roadblocks small dams have, possibly so they can apply for some of the $$ mentioned in this thread.

 

[memilanuk]

Unless Colorado has one *hell* of a lot more dams than I think they do, "12,000 megawatts" is someone's pipe dream.

Don't get me wrong... I generally am a proponent of anything backed by "big iron" over other 'lesser' forms of generation - mainly for the sake of system resilience during transients, which lets face it, are a fact of life on any grid-tied system.

I'm not saying that there isn't room to more fully harness the resources we have... but it's not quite as simple as 'throw a generator on it'. Most small stream-fed dams aren't going to have enough net head, or constant enough flow, to be worth the effort of installing and maintaining the necessary equipment. Dealing with the power marketing, scheduling and sale of such a variable energy source... would be challenging.

All things that can (in theory) be overcome... eventually.

 

[svetz]

Unless Colorado has one *hell* of a lot more dams than I think they do, "12,000 megawatts" is someone's pipe dream....

The law is for more than Colorado. But how high would the dam need to be to generate power?

Here's a map that portrays "major" dams in the United States:

...The map layer was created by extracting dams 50 feet or more in height, or with a normal storage capacity of 5,000 acre-feet or more, or with a maximum storage capacity of 25,000 acre-feet or more, from the 79,777 dams in the U.S. Army Corps of Engineers National Inventory of Dams....

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The problem with the map above is you don't know which already have power and which are more water basins for water control.
For example, Florida looks like it has a lot of dam sites...but Florida is mostly flat (the highest point is 345'). If you zoom in it looks like it's mostly water control and probably huge reservoirs that are 1 to 2' high.

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There must be some sort of report on this... I'll hunt around for it.

 

[svetz]

Found the report!

In contrast to the roughly 2,500 dams that provide 78 gigawatts (GW) 1 of conventional and 22 GW of pumped-storage hydropower, the United States has more than 80,000 non-powered dams (NPDs)—dams that do not produce electricity—providing a variety of services ranging from water supply to inland navigation. Importantly, many of the monetary costs and environmental impacts of dam construction have already been incurred at NPDs, so adding power to the existing dam structure can often be achieved at lower cost, with less risk, and in a shorter timeframe than development requiring new dam construction.

Adding power to U.S. NPDs has the potential to add up to 12 GW (12,000 megawatts or MW) of new renewable capacity—a potential equivalent to increasing the size of the existing conventional hydropower fleet by 15%. A majority of this potential is concentrated in just 100 NPDs, which could contribute approximately 8 GW of clean, reliable hydropower; the top 10 facilities alone could add up to 3 GW of new hydropower.

At a guess, I'd say the top 10 (big blue dots below) are a shoe-in.

Eighty-one of the 100 top NPDs are U.S. Army Corps of Engineers (USACE) facilities, many of which, including all of the top 10, are navigation locks on the Ohio River, Mississippi River, Alabama River, and Arkansas River, as well as their major tributaries. T

This study also shows that dams owned by the U.S. Bureau of Reclamation hold the potential to add approximately 260 MW of capacity

Here's a map on NPDs where they believe more than 1 MW could be generated, probably includes the BWM dams:

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[fhmhpr]

I'm not saying that there isn't room to more fully harness the resources we have... but it's not quite as simple as 'throw a generator on it'. Most small stream-fed dams aren't going to have enough net head, or constant enough flow, to be worth the effort of installing and maintaining the necessary equipment. Dealing with the power marketing, scheduling and sale of such a variable energy source... would be challenging.

The main issue in hydro is always the "head," or the distance between the top of the water and the generator. Power is derived by a combination of head and flow (the total volume of water).

In some places, the dam can be well-upstream of the powerhouse. One good example is a series of powerhouses on the Ocoee River in Tennessee, where a pipe system brings the reliable portion of the water downhill to the powerhouse under pressure from the dam above. Sometimes these powerhouses are miles downriver from the dam itself, which effectively increases the "height" of the dam by several meters, and which likewise increases the power of the system.

That's completely impractical in Florida, but in a number of other places (like Colorado), the head on a small river or creek can be increased by building the powerhouse further downstream, possibly in places that are more accessible than the base of the dam itself.

 

[memilanuk]

The technical terms you are looking for are 'penstock' and 'net head'.

Not a bad idea, but again, considerable engineering (and maintenance) involved, plus now you have get additional property and/or easements as you expand the project away from the dam itself. I still think that the variability of the water levels - and by extension, the net head - wouldn't pencil out in the end.

Much of which is stuff that would be necessary regardless of the energy source, but you would not believe how fast people go from 'green' to 'NIMBY', especially when it's suddenly in *their* back yard.

 

[Diysolar123]

if you want to INCREASE the energy harvesting of local resources such as rivers (and solar) you absolutely positively do NOT want a government "bill"...
You want to eliminate regulations that stop people from doing things; creating more laws/regulations will just make it much much worse.
There rarely been a government regulation to help has which has not over time turned into a detriment; it happens all the time.
It is just the nature of any group or organization to want to control more over time, it always happens; people in power want, well, more power.

generating hydro power actually has quite a few constraints so you cannot just say "hey look, there is a dam, looks like 5MW of power to me!!"

applause to svetz who at least has enough common sense to realize flood plains do not exactly generate massive head pressure to run a turbine ;-)

could you imagine to cost to re-engineer a high flow dam... avoid damaging existing structure, land rights to tunnel/route new spillways, need to do a wildlife impact assessment, local interruptions to, well, everything...for how long?? large scale hydro plants take many years to build, trying to "back build" one will probably take just as long and cost twice as much. Local governments often spend years just trying to re-build a 1/2mile of road.

I have no degree in engineering hydrology but you can see many of the issues that will pop up with just a bit of experience and education.
I have over many decades seen similar things happen with software/hardware. An "executive" sees a product (software or hardware) that does half of what they want, so their response is "lets just change it to do what we need, it will be simple as half the work has been done"... I mean it "sounds logical"..right... this is the trap soooo many people fall into, on the surface it "sounds" reasonable.

reverse engineering something that does part of what you want so you can figure out how to add in the part which is missing to meet your needs has, 100% of the time, taken more effort than if you had just started from scratch and what you re-used was the important "lessons learned"...

put money into fusion research and get a real solution.

although I think we really are running out of critical thinking scientists and engineers...sigh...