Is my creek too little for hydro power?

I just bought 5 acres with a small creek that runs year round. We are currently in quite the drought and according to my neighbor the creek is the lowest it's ever been in 35+ years. Currently flowing at about 10 gpm. I suspect average is about 20-25 gpm bu I'm not certain. And I can get about 4-5 feet of drop if I dam it up. Can anyone tell me whether it's even worthwhile trying to get electricity out of this and point me in the right direction of information? I'm guessing most practical way to go is to build a 4 foot diameter water wheel, find a little motor and gear it properly and I might get enough energy to power a portion of my energy consumption but I'm afraid maybe it's too small a portion to be worth the effort. What do you guys think?

Nick ; Is this land off grid ? or is street power readily available ?  You have to weigh your options about cost of street power versus living off grid.  I made them remove the power from my home in 1986 ... its still out there on my property, i'm just not connected to it.  I choose to do this and will admit that I have spent way more money than if I had let them leave the power hooked up. I Do Not REGRET IT ! Your water probably has hydro potential and everybody has some solar potential , lots of equipment out there for very nice off grid living.  Living off grid is not for everybody but for those of us who do its a way of life !

It has road access and a power pole but no power from when there used to be a house there 20 years ago. I was thinking, when I build a house, I could get power back to the pole, then get solar, and get hydro power from creek. That way I always have city power for back up in case I don't have enough from solar and hydro.

From what you have said, and from the size of your creek, and the head (drop) that you have (which isn't much), I'd say (if you have good winter Sun especially) that you are better off investing your personal money and energy in Solar, or a combo with Solar, possibly including Grid power.  You can get power off this creek, but it will not amount to much considering the cash, time, and effort of building the system.  

nick bramlett wrote:about 10 gpm.
about 4-5 feet of drop  

That would provide about 8 watts of power.

That 8 watts is if my system is 100% efficient, which I can assure you bc no system is. More likely it'll be 50% efficient and producing 4 watts. How can I put that 4 watts into perspective? If I've got a 60 watt light bulb, how long will I have to charge a battery in order to save up enough energy to power a light bulb for an hour? 15 hours?? If that's the case then it's definitely not worth it. I say that bc in order to make it work, I'd have to build retaining walls in addition to the hydro generator in order to get the requisite head. Which brings me to my next question, is 4-5 drop and 10gpm enough to power a ram pump that way I could pump water higher up on. Property to use for something like watering growies? The delimma here is this creek flows through a culvert under a driveway and the culvert is complete rusted out, so before I replace it I need to figure out what my future plans are for that part of creek. If I'm going to use it to power something then I'll have to dam it up which means making a bridge rather than simply replacing the culvert. Whereas if I determined that the creek is too little to really power anything then I'll save a ton of money by not building bridge and instead just simply replacing the culvert.

Here's a pic. Driveway runs above that pipe. To get the head I would need to build a few retaining walls and a dam. Or I could forego powering something with creek and save money by just replacing the culvert.

Welp, decided that to make it worthwhile I would need at least 20-40 gpm. I'd probably peak at around that level in spring but since I can't pull that off year round I'mma just scrap the whole idea. Thanks for the input though.

Hi Nick;  I think your making the correct choice. After seeing the amount of water from your culvert you just don't have enough to make a usable amount of power. I make 120 + watts with hydro and 500 watts with solar and its still not enough, we run a generator when we have high draw needs.  Your site  may have solar potential  but if your building a house having street power available is oh so nice. You can always work on an alt energy system at a later date.  Congrats on being a new property owner !

You have running water on your property, and that is a major plus in land development, whether piped gravity fed to your house, to a pond, to irrigation, or whatever.  So many people would LOVE to have a creek.  One major benefit of having a tiny creek (as opposed to a larger one) is that it's less apt to cause major problems to your infrastructure in a major peak event and is more easy to contain if it does show potential to do so.

A rough estimate of power output from hydro is head (ft) x flow (gpm) / 10, which accounts for an efficiency of about 50%. 5 ft x 10 gpm/10 is 5 Watts at best. That would hardly be worth it, and I also know of no commercially available turbine that would operate at those numbers. The LH100 from Energy Systems and Design, probably the most common low-head turbine, needs hundreds of gallons per minute. Bummer!

You might consider installing a ram pump and save the electricity for pumping water.  

Yes, you have plenty of flow to run a ram pump. You can deliver a small but constant amount of water several times the drop in height; how high might you need to deliver it, and how far away?

You also don't need to have a dam 4 or 5 feet high, all you have to do is make a feed pool so you can have a secure inlet, then run a pipe as far as needed to drop as far as necessary to the ram position. My father installed a hydraulic ram to pump water over 500' from our spring and up maybe 10-20' above spring level, with a 3/4" hdpe pipe 50-60' long and 20' down.

General note about micro-hydro power:

You are much, MUCH better off with a small flow and large head, than large flow and small head.  The only equipment that can tackle high flow and low head are expen$$$ive, industrial, commercial, municipal-scale plants that just don't make any sense for an off-grid application.

And -- it's all about the loads.  If you use very little juice, you have many more options.

There are low-head options for heads of 4-10 feet and relatively high flow rates, like the ES&D LH-1000, and some low-efficiency home-brew options (search Home Power for articles), but the tiny ES&D Stream Engine, Water Baby and Water Buddy are all tried & true commercial products: http://www.microhydropower.com/.

I've only helped install 2 systems (micro-hydro is all but impossible to push through permitting here in Vermont, so don't-ask-don't-tell off-grid power is about it), and both came from ES&D.  Those crafty Canadians have some really good stuff.

Clear skies,

Brad Vietje
Newbury, VT