I was wondering if anyone would help me plan out a hydroelectric system? I have almost zero knowledge when it comes to this stuff. I have a seasonal creek that runs through 4 culvert pipes which I think are around 18” in diameter. This summer I have to replace 2 of them due to a collapse from rust and I plan to reinforce both the inlets and outlets with concrete. In the process I was thinking of installing screw gates on 3 inlets to direct the flow into one culvert pipe when the water gets low. On the other side I wanted to install a bracket to hold a removable generator and turbine so I can take it off when there is no water flowing and to service/make repairs. There is no drop in the water. It’s just a flowing stream. I know I need to calculate flow rate/gpm but I’m not sure how to do that without a flow meter. Once I get the gpm and head pressure(which is almost zero) what turbine would be the best for that setup. I plan to build it myself. After I get the turbine built, how do I figure out the size of generator? I’ve searched forums and websites but it’s confusing and seems like there are so many different opinions. I know I’m asking a lot but any help would be appreciated. I will post pictures asap. Thanks!
Need help with hydroelectric system design
- Thread starter Macrosse1
- Start date
Gather a tape measure a stop watch and a stick. Measure the length of the culvert pipe, time how long it takes for the stick to get through the pipe. This gives you an approximate velocity in feet per second. Assuming the stick didn't get stuck. Measure how deep the water is in the pipes. Make your geometry teacher proud and calculate the area of the pipe openings filled with water. Convert that area to square feet. Multiply that by the length of the pipe then convert from cubic feet to gallons. Divide by the time.
Convert to gallons per min or similar. Measure the change in elevation between the entrance and exit of the pipe, measure how high the water could get before flowing over top. From the change in height/depth of the water you can convert from to pressure. Knowing the pressures and the flow you can calculate how much power that is in electrical terms and decide how much $ and effort you want to put into the project. Sounds like fun, let us know what you learn.
NC_hydro
Solar Wizard
If you can get a 5 gallon bucket under the end of the culvert then you can time how long it takes to fill that. Easy enough to calculate how many gallons per minute from that. I can tell you with nearly zero drop it’s going to take a lot of water for any worthwhile power. Have any pictures of the water coming thru the culverts?
For the generator, a permanent magnet style generator is the way to go. You can find them for hydro or wind applications. Don’t waste your time with car alternators.
For the generator, a permanent magnet style generator is the way to go. You can find them for hydro or wind applications. Don’t waste your time with car alternators.
ksmithaz1
Solar / EV Junkie
Your money is better spent on solar. In fact a windmill, would probably be better. If you just want to throw a couple grand and time at it for educational purpose by all means, but don't expect to extract much useful power for your time effort and money. There are other threads on this very topic in this forum.
OzSolar
Whatever you did, that's what you planned.
You may find a turbine that claims it work in your situation but you won't find any actual users to support that claim.
Microhydro needs drop AND flow. When H (net head) = 0 there's no getting away from the final result being 0. Sadly, math gets in the way of your idea. Better to hear it now than later, sorry.
Calculating Microhydro Output
It turns out that calculating the approximate power output of a microhydro system is not terribly difficult. According to the U.S. DOE, a typical system has an efficiency of about 53%. This includes losses from the nozzle, the wiring, the generator, and a few other things. The power of a microhydro system with this efficiency is approximately:- power = net head x flow /10
- power = electric power in W
- net head = the gross head in ft including the head loss in the penstock
- flow = flow of water in gal/min
- 10 = conversion factor (this can range from 8 - 12, with 10 being about average)
ksmithaz1
Solar / EV Junkie
There are some cute little paddle wheels you can buy cheap to run landscaping LED's, they produce a few watts if you have actual flow. . . And if the water is flowing, ... there is a drop, otherwise you would have a pond, not a stream. Hydro requires a lot of effort. I recommend you do some research, I found it interesting, I did a bunch back before the internet for a town I was in that needed a new dam, thought I was going to solve the worlds problems, well at least the towns, by providing cheap power to the whole town. It doesn't really work unless it's at very large scale, and it's a byproduct from flood/water control, ie you need to build it anyway.
NC_hydro
Solar Wizard
It works great if you have a lot of head pressure or a lot of flow and little bit of head 8ft+.
It is more “work” than solar mostly related to keeping your intake cleared. A proper design helps reduce that. Even a small 25gpm flow with a high pressure is huge when you consider it’s 24/7. Especially in winter or cloudy days. If you can get a 3ft drop with a 12”+ sized culvert full of water then you may have something. Without a huge investment in pipe..
It is more “work” than solar mostly related to keeping your intake cleared. A proper design helps reduce that. Even a small 25gpm flow with a high pressure is huge when you consider it’s 24/7. Especially in winter or cloudy days. If you can get a 3ft drop with a 12”+ sized culvert full of water then you may have something. Without a huge investment in pipe..
ksmithaz1
Solar / EV Junkie
Still very high maintenance. At the end of the day you are building a dam, and anything you are pushing large volumes of water thru is going to require a lot of maintenance, especially as it gets older. Filtering the catch basin is only part 1. And a 12" pipe is serious water volume.Over the long haul it gets expensive as the water beats up your infrastructure. Water from the colorado made the grand canyon.
NC_hydro
Solar Wizard
Lol calm down. I’ve been doing hydro since 2009. Not sure you’re angle or why you’re sensationalizing everything lol.
Sure it requires maintenance and staying on top of things but it’s very rewarding and it’s not rocket science.
Here's some inspiration for you:
5kw Poncelet Wheel Project
A Poncelet wheel rides in the flow without diverting it or needing it to be channeled separately. It's a practical solution when you have no real slope to use for building a pressure head. Instead it requires only flow, but the flow has to be strong enough to apply a significant torque to the wheel.
I've also researched low-head hydro systems and they are more difficult to work with. You can't use something like a Pelton wheel or Turgo turbine--those require pressure. At the lowest head levels the best turbine in my opinion was the good old-fashioned water wheel. A water wheel works on the weight of water, not its pressure. There are advantages and disadvantages to water wheels. They are large, cumbersome, and heavy. They are inefficient compared to the impulse turbines. I don't know if anyone sells them, so one gets to make his own. But one advantage when coupling this to a generator is that the wheel itself will run at the speed of gravity, and there should be no danger of runaway, nor need for overspin protection on the generator if the gearing is properly matched.
With zero head, the water wheel can be simply powered by the stream itself, which flows under the wheel. With a few feet of drop, a breastshot setup may be used, and is more efficient. One of the most efficient, if one has enough drop to reach the top of the wheel (which can vary in diameter as well), is the overshot form running in reverse direction such that both the stream itself and the water dropped at the top of the wheel power the spin.
There are other options, however, when the flow can be force-fed through a pipe. You might look at a crossflow turbine.
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