This guy gets an A+ in my book. His 3 kW homebrewed. grid-tied, fully licensed and permitted, low-head undershot wheel has been in operation since 1983, with very little downtime. It's near Midway, Utah, on a small, spring-fed tributary of the Middle Provo River. The water is relatively warm so near the source.... so it never freezes.
We get lots of questions about low-head undershot hydropower, especially floating units. The numbers are pretty depressing.....if you don't have lots of head or don't want to lay lots of large-diameter pipe, you have to build a big, mechanical "thing." Which describes this one pretty well.
The builder and his wife said that they just watched this huge amount of energy flow by for so long, and decided to harvest it. They did research at the library, contacted the numerous authorities. Nobody had any answers, then over the course of 3 years they built, experimented, negotiated. They admit making themselves pests to AHJs, and suppliers of generators, gearboxes, grid-tie inverters, and sundry items. There's a fish ladder to the right side of the video, better visible in the aerial photo at the bottom of this post.
BUT IT ALL WORKED!
Quote: "They all told me I couldn't make any power from an undershot wheel, and I said B***S**t. How else could I do it here?"
I have to agree! Tough site.
Specs: During normal operation, the wheel spins at 14 RPM, geared up 125:1 into a 3-phase alternator that feeds a standard (for 1983, that is) grid-tie wind turbine alternator. If the grid cuts out from a blackout, the wheel overspeeds (you can see and hear it in the video below--and you can hear the big grid tie breaker when he throws it). A flyball counterweight system then grabs the counterweight cable, and the entire unit lifts out of the water. It takes a manual reset of the counterweights to reset it all (last part of video).
The wheel itself was damaged by debris floating down in high water in spring 2010, so by the meters (in video) it was making about 1.2 kW when i visited. When all the paddles are in place, it would be making about 3kW and spinning at a higher RPM.
http://www.youtube.com/watch?v=P88O6Gl-yX4You can clearly see the hydro unit at center top of the aerial photo below, in the tributary coming in from top center and spring fed ponds top left. The Middle Provo River is at far right. The fish ladder is at right of the hydro unit. I am am quite sure the unit *improved* fish habitat downstream, from aereating the water. I actually went there to flyfish right after Christmas.....the folks I was staying with on this fishing trip had done some remodel work at the house, and the owner gave us all permission to fish... So I observed the hydro unit, caught 3 nice trouts, spent the rest of the day at the hydro unit, then came back the next day to film the hydro unit and interview them for this posting!
So, all I can say is "Thanks Lary and Dottie! We really enjoyed your hospitality. And even if none of your neighbors give a s**t about your water wheel, there's lots of other folks all over the world who will be both educated--and inspired--by what you accomplished from a really difficult situation!"
DAN FINK
Buckville Energy Consulting
NABCEP - IREC - ISPQ Accredited Continuing Education Providers