off grid alternative energy harvesting

So, I've been living off grid in Central Vermont for four years now.  I have a couple solar panels and an inverter and a couple car batteries, but never bothered hooking them up when we moved.   Insted, the focus has been making due without electricity, not generating it ourselves.  In the winter, I go to be early or use candles and oil lamps.  (Maybe our sheep tallow and bay berries will be helpful for this someday, but I'm currently buying lamp fuel.)  Used to buy ice in the summer, but don't bother any more.  Between pressure canning and one pot cooking, I've been able to minimize food waste without a fridge.  Cook with propane and woodstove.  We compost our human waste.  I have a 15 gallon steel kettle next to the indoor sink that I heat up dishwashing water with.  We get our water from a well way uphill of the cabin and have gravity fed water for our animals and I ran the piping right through the cabin to be able to use it at the indoor sink for both hot from the kettle and cold from the line.  So long as it flows, it doesn't freeze even when it got down to -30F.  Anyway, I was wondering if anyone has experience with microhydro on a 3/4" gravity line.  We have a bunch of pressure from the hill and could consider putting something in line before the final outlet for the pasture, (not sure what it would be rated, but I can shoot water 25' high from the garden hose if I want to.)  Not sure what I'd use the power for, but it would be nice to be able to grind/blend in the kitchen.  (Currently only use our generator for juicing fresh forage, and when the sheep sheerer came last week she used it.)  I charge my computer and devices with mikita batteries that I charge while driving around in the car and truck.  Don't have a cel phone or internet.  Why do people think they need so much power?
Anyway, I do want a ceiling fan in the winter and I know I can figure out how to get the wood stove to power it.  Anyone have a simple method for this?  I don't need to generate electricity, just turn a fan above the stove would be nice.

I use a few of these they work very well.

https://www.amazon.com/s?k=woodstove+fan&ref=nb_sb_noss

You can also look in to generation using TEG's. These type of fans are powered with a TEG.

16 years off grid in VA myself but I have a pretty good solar power system now.

A so called “Pump as turbine” should work, especially if selected for the right pressure and  flow rate.

Any idea of what your water rate would look like?  I figure about 30 watts could be generated when flowing 1 gallon per minute.


1 gal/min , 0.063 L/s
10.5 psi , 0.07 MPa
30 W assuming 70% efficient turbine

Pump specs (wild estimate)
~150 watt, 24VDC, 6.25A (0.2 HP)

Generator output:
30 W, 12VDC, 2.5A

So your question seems to be asking how much electricity can I make and use per day. To answer that we will need to konw whats the head is in "feet" and what the flow rate is in "gallons per minutes"

Net Hourly Power = 1/5 * Efficiency * Head * Flow
Net Hourly Power = 1/5 * 50% * Head * Flow
Net Hourly Power = 1/10 * Head * Flow

lets suppose you could make 60watts (1/10 * 60ft * 10gpm), then your daily production would be
Daily Production = Net Power * 24hr/day
Daily Production = 60W * 24hr/day
Daily Production = 1440WH/day aka 1.4KWH/day
(this could easily power alot,  LED lights = 250W/day, tablets/laptops = 240W/day , phones = 50W/day, wifi= 100W/day, small fridge = 550W/day, instapot=250W)

But to answer you actual question a 36inch ceiling fan will use around 55W per hour, so it would be nice to have that tied to the micro hydro and have it running 24/7

Hi F Rose;
I live with gravity water and micro hydro.
It sounds like you have very small power requirements.
Something like this from Amazon might be a good option for you.
Water Flow Generator Turbine Generator Hydroelectric Micro Hydro Generator 1/2 Inch Portable Water Charger (5V)
A complete working hydro system has many components that are not cheap.
Your current 3/4" supply line makes investing in a full size hydro not economical, however small units like the one above have almost no investment and might be worth your time.

He said he could spray water 25 ft [up?]. That means he has about 25 ft of head (at that flow rate).

10 gal/min, 24 hrs/day is 14,400 gal/day.  
I’d be concerned about running the well dry.  

I looked at those Amazon turbines. The specs are highly inconsistent. Best I can tell, the little $10-$15 ones (in yellow&clear, or black) that claim 10 W may produce 2.5 Watts max. There’s a $30 one with a “35 watt” typo, later claims 3.5 watts.

Better to go solar I think. Lasts much longer, less maintenance.

Mike Philips wrote:He said he could spray water 25 ft [up?]. That means he has about 25 ft of head (at that flow rate).

10 gal/min, 24 hrs/day is 14,400 gal/day.  
I’d be concerned about running the well dry.  

I looked at those Amazon turbines. The specs are highly inconsistent. Best I can tell, the little $10-$15 ones (in yellow&clear, or black) that claim 10 W may produce 2.5 Watts max. There’s a $30 one with a “35 watt” typo, later claims 3.5 watts.

Better to go solar I think. Lasts much longer, less maintenance.

I'm not at all concerned about the well running dry since this water isn't even coming from the well- it's from the overflow of the well and it never stops running even in the dryest of weather.  The line starts as 2" up on the hill and turns into 1.5" for most of the run.  When it gets to the elevation of the cabin, maybe 100' downhill over at least a quarter mile, I'm currently bleeding out most of the water and sending it to the winter pig pasture, and there is a split there that sends water to the cabin in a .75" pipe, I'm also bleeding out water again before it gets to the cabin for a sheep pasture, and then after the kitchen sink I can blast a garden hose 25' straight up if I take all of the remaining flow before it goes to the pigs summer pasture.  If I were serious about power generation, I'm sure there's enough pressure to invest in a system, but I'd be happy with just a little for cheap until my energy needs go up.  I think I used 5 gallons of gas in the generation last year and have not bothered hooking up a 200W solar system that I already have.

I want to power a ceiling fan- it could be mechanical instead of electric.

Great. So a ceiling fan uses about 50 W on low and 100 W on high.

I think a 200 W solar system is close to being able to run a fan when it’s sunny, but not when it’s cloudy.

For hydro, I’m thinking that the simplest way would be to use a brushed-DC motor as the generator, (whether this was purchased as part of a pump or attached separately after the fact.). (One source of these, especially large ones, is from old treadmill exercise equipment.)

A “brushless DC” motor and a rectifier also works. These are used on e-scooters, e-bikes.

Other more common motors like AC/DC-universal motors (in vacuums) and induction motors (fans, pumps, most large motors) could theoretically be used, but the electronics can be somewhat more complicated, and the efficiency is somewhat lower.

Heck, you could even have a water-wheel directly driving a ceiling fan if you wanted to, it’s up to you.

Mike Philips wrote:Heck, you could even have a water-wheel directly driving a ceiling fan if you wanted to, it’s up to you.

This sounds way simplier.  I don't use electricity for anything.

Okay so I figure a typical ceiling fan would need to be driven at something like 200-500 RPM, and 1.5-2 ft-lbs of torque.

50.   60.    75.   100 watts
200  300  380 525 RPM
20.   30.    36.   50 Rad/s
2.5    2.      2.      2 Nm  (1.5 ft*lb)

So ballpark figure for 25 ft head and 10 gal/min, a suitable pump to use as a turbine would be able to operate efficiently (70% assumed), while pushing 14.1 ft head at 6.8 gal/min flow rate.