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There's a lot of low hanging fruit in the hydro landscape that people miss. I have a rivulet that runs near my house. It has weir dams at a few locations on it's path down our mountain, IT wouldn't be that hard to extract energy from the constant flowing water there to feed into the grid. There are turbines that exist to extract energy from a meter high head of water.

Everyone thinks about power like you need one big dam, or one big plant (coal or otherwise). There's a lot of small fast flowing streams that have potential to create extra energy.

I think hydro needs to be reimagined. IT always need to flood valleys to be in the mix.



I dunno, patching up every little creek and flow of water we can find sounds to me like hydro just can't generate enough energy.


That really depends on what percentage of water's potential energy is expended in small creeks and the like vs big rivers.

I actually have no idea how to estimate that. Anyone have a good estimate on that? Intuitively, I'm thinking that most of those rivers are fed by many small streams, so it would be approximately equal. I'm entirely unsure of that though so treat it as having huge error bars.


The problem becomes one of how spread out the energy is.

Sure the water in that creek might be falling hundreds of meters, or even kilometers, but without a dam the height differential at your generator is only going to he a few metres at best. Enough to power the lighting, fridge, and washing machine in the houses that the creeks happen to run by, but not much else.

With the advent of long lasting perovskites and (hopefully) some less polluting battery technologies you're not even better off cost-wise.

You might be able to do something with a long pipe parallel to the creek to get more head, but then you're going to spend a lot of your energy on wall friction unless it's very wide.


> Sure the water in that creek might be falling hundreds of meters, or even kilometers, but without a dam the height differential at your generator is only going to he a few metres at best. Enough to power the lighting, fridge, and washing machine in the houses that the creeks happen to run by, but not much else.

Could be, but that's a bunch of stuff you don't have to power with the existing system. Given how many creeks there are, that seems like it could really add up.

> With the advent of long lasting perovskites and (hopefully) some less polluting battery technologies you're not even better off cost-wise.

That's fair. I've learned in my life that I don't have a good intuition for what the costs of large infrastructure projects are.


It would also have a tremendously negative impact on the local environment. Even tiny dams cause big disruptions to the riparian ecosystem.


Who is going to run all the little dams and turbines, though? And how would it ever be cost effective to do so? There is so much maintenance on small lakes that don’t even have a turbine (mainly dealing with silt, which accumulates steadily and is hugely expensive to remove).


Surely theres is wildlife that depends on the speed of at least some of these bodies of water, right?


Yeah in this example, the water is never stopped. Not even the flow rate, It's just held back for a moment to create a convenient potential energy situation. This https://www.youtube.com/watch?v=Bhyi1DjGti8 Is something that could be built near a bus stop near my house and not negatively impact anyone outside of the initial construction.




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