Author Options:

Hydroelectric Generator Answered

This is my first topic, so I need your opinion - is this possible? I have all of these items.


If you're planning on charging the battery when electricity is expensive, then using mains electricity to pump the water back up at off-peak times, then yes, though the financial savings will be very small at this scale. The bigger the tanks/batteries the better.



If you are planning on using the system to provide a never-ending supply of electricity, then, no - friction, turbulence, inverter losses, electrical resistance etc etc will all mean that it grinds to a halt in a few minutes, even moments.

Thank You very much! I can use grid electricity for pump, because it's only 25w. Just one device in my house uses 2000w and there are 3 of them + lights, computers, TV-s, and other stuff, so 25w more is nothing compared to that. And I've been thinking to put water tank 1 higher, like 5-6m. I would like You to help me more with this project, because I need to lower my electricity bill at least for 10%. Also I have a small creek about 500 m downhill of my house and I can build micro hydro generator there, but main problem is transporting electricity back home.

Take a point high up the creek.
Add a pipe that runs from there into your tank, also add a shutoff or overflow.
This is how we fill tanks from a creek here in The Land Downunder. ;)
Other option if distance is too far would be to use a ram pump to get the water into the tank without any electricity - look it up ;)

It would be very expensive to buy 500 m of tubes from a creek to my tank. I can build hydro turbine with generator on creek, but I need a solution to transport electricity back home. It seems simple, buy 500m of electric cable and project done, but there are a lot of houses, I can't just dig canal through neighbors yard and get cable to my house like that. Any ideas are welcome!

Well, if you need electircal energy to get the water back in the tank then you are wasting a lot more than you might think.
If in doubt use at least decent sized solar panels ;)
In the right area a wind powered pump on top of your tank will help too.

Have ever thought of including at least the neighbours along the line for water?
At my sisters place they had a suitable creek three properties up and after explaining what they wanted to do everyone jumped on it and they all ram pumps and tanks.
Was just for water use during the summer though and not for electricity but it does help to keep initial and maintenance costs quite low.

I did some guesstimations based on jet turbines available here to gerenate home electricity.
To reach a target of 500W on a connected generator the smallest possible turbine requires a waterflow of at least 140L per minute with a minimum height differential from turbine to water inlet of 15m.
Mind you this is a 3 jet model with 5 "scoops" driven.
Smaller, single jet generators will use less water but still require decent pressure to work - and they will struggle to get 500W.
With that in mind even a very efficient pump will require more kWh to pump the water back into the tank than what the generator will deliver.
And with the required flowrate it only takes simple math to calculate the need for almost 10000 liters of water to run the generator for one hour....
I hope you have more efficient turbines available where you are.

Now You opened my eyes. Now I understand the reality. Thank You for explanation!

Well, it is nice to know you can see now but that should not stop you from trying anyway.
If you eliminate the need for mains power to get the water up the tank you are half way there.
Main focus should be on a suitable turbine/generator combo.
Off-grid turbines are usually only designed with reliability in mind assuming water is available with no limits, like from a running creek or small lake.
But there are other options worth trying, like a turbo from a small car or even a water pump from a slightly bigger car or small truck.
Take what you can get for free or dirt cheap and experiment, focus on great torque at the shaft with the water use as little as possible.
And: You don't need to produce a lot of amps, you do need to produce a lot of kWh to charge the battery ;)
Meaning it is often better to use a generator that has a higher output in Volts than what you actually need.
Take this example to get you thinking:
A generator that requires at least 1000rpm to produce 500W at 24V will only give a fraction of that power when running slower.
But a generator able to deliver 48V and 500W at the same rpm will still give you enough volts to keep charging the battery when running slower.
With that in mind you can adjust the water flow within certain limits to optimise water use.
Same story for the torque required to run the generator.
Ideally you want the turbine system to only have little reserves left when the generator is under full capacity, everything more will "waste" water.
When you found your ideal match for generator and turbine do some math to figure out what tank size you need for a full charge of the battery in question.

Down here folks usually only bother with water turbines if a creek with sufficient water flow is available.
And still in most cases only as a backup for cloudy days or the winter time with not enough sunlight for solar power.
Small wind turbines are now getting more attention as the modern types offer grid syncronisation or can directly charge big battery systems together with the solar panels.
Currently a friend of mine is trying to improve the remote home he bought a few years back.
No mains power, bottled gas and apart from that only batteries and solar panels.
The later was already upgraded to 12kW max capacity on a sunny day.
Now we work on using the wood fired heater as a steam generator for a small turbine.
The idea is to make a double walled flu and use the exhaust heat to generate steam.
Not really easy but thankfully my friend is a licensed boiler maker, so things might actually work out one way or the other.
If in doubt it will still help the hot water system to save on gas.

I will continue to work on my project, I need to buy pelton turbine first and do some testing. I really like the way You think, a lot of creativity and hard work, I wish we could work together. Idea with steam power is really good, steam gives a lot of power. Also, I've been thinking about biogas stuff, because a lot of people in my place are farmers, a lot of cows and sheep. Do You know something about making and using biogas?

There are several third world projects involving bio gas to generate heat and electricity.
Some small communities even managed to do without any petrol generators for backup.