Post #1639241

2026-04-24 10:36 UTC

This morning&#39;s 3am bright idea: home hydro! We have options for residential solar and wind power already, so why not also hydro? Rain falls from the sky onto your roof, then flows into the gutters, then down a drainpipe to the ground and on into the stormwater system. What if we put a bunch of tiny spinny wheels inside the drainpipe? Think of all the electricity we could generate during all those once-in-a-century tropical storms that have started hitting us multiple times a year! I guess now we just need some engineers to redesign the basic drainpipe to optimise spinny wheel spinning, and make it accessible for maintenance. #solarpunk #renewables #sustainability

Replies (4)

@kirk@social.coop 2026-04-24 10:49

@mwt I think the main issue would be lack of height... The main driver in a hydropower system besides flow rate is the height of the water column. But there are a lot of cool systems around if you search for "pico hydro", though they are geography-specific, often in rural valleys. And you need to a run a long pipe up a hill usually. But they're awesome when they work because even if it's "low-power" compared to say a solar panel, it's often 24/7 so you can harvest a lot of energy with a small turbine. There is also this small project recently funded in the EU: https://lauds.eu/open-calls/2/democratizing-energy-through-diy-renewable-energy-solutions/flow-optimized-water-energy-recovery-flower They're trying to recover energy from mains water systems.

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@TheGreatLlama@kolektiva.social 2026-04-24 10:53

@mwt I have seen "micro hydro" used for off the grid homesteads, but that's generally small streams to provide power for a household. I think it would be hard to make it scale at the level you're talking, but I imagine storm drains might get enough runoff to be workable, and a useful boost during weather not helpful for solar.

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@leighelse@mastodon.nz 2026-04-24 20:25

@mwt Sadly I think the actual output would be infinitesimal. The payback period on installation and connection costs (on a quick estimate) would be in multiple human lifetimes.

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@wachoperro@rebel.ar 2026-04-25 00:03

@mwt May i interest you in some QuintBuilds? https://youtu.be/ZkcSPpPpRyU He already tried a pelton wheel and a "proper" hydro turbine, and the power isn't like... A lot... But it's free!* *Ignoring labor and material costs :P

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