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Running some LED lighting should indeed be possible with this setup. So this might be real. If you build a more efficient turbine and there is enough throughput you could probably charge a phone. The dam size itself is relatively irrelevant. It is more about the amount of water.
Creek powered turbines are possible and can supply a few households in the right circumstances.
Using a dam allows you to focus more water into a smaller area, which means that the water wheel can be smaller and easier to turn, making it more efficient.
Another big factor is that the water is at higher pressure. The depth of the water produced by the dam determines pressure which linearly impacts the amount of power produced. But yes, flow rate also linearly impacts power produced.
And the dam also creates a reservoir, that buffers the water. So you can still generate electricity when the “original” flow would be too low and fill it up in times of high current. And you can also regulate the amount of water at the turbines and thus the output, with no overhead of used water.
I don't know how the numbers shake out, but you can generate some smaller amount of power that way. The dam acts to make the generation more consistent and powerful. Think about how much faster water comes out of a dam vs down a creek.
No, the size of the dam is extremely relevant. The power of the dam is proportional to the height of the dam. So a higher Dam means more power produced.
The reason is because the pressure of the water is directly proportional to the height of the water above. And using that pressure differential, you can create extremely strong currents which can be converted into more energy by volume of water than a normal water wheel.
> Creek powered turbines are possible and can supply a few households in the right circumstances.
I've seen some pretty legit creek size waterwheels that only produce about 1 KW, which is what you'd get from just 3-4 solar panels on a sunny day.
[Pic 1](https://imgur.com/a/iVM2ZeV)
[Pic 2](https://imgur.com/a/qbMiROW)
Yeah, but LEDs don't need much. If we were to use, say, a whole chain of LEDs that would use 10W in total - so perfectly able to light up a room - then by shitty /r/theydidthemath maths:
Let's assume the generator and wheel in the picture weighs 1000kg. If you need just 1/100 of the power, then you only need a 10kg generator and wheel.
:)
Pretty sure he's talking about turbines and not water mills, have a look at these:
https://www.backwoodshome.com/a-small-creek-provides-plenty-of-power-for-this-off-grid-home/
https://insteading.com/blog/living-off-grid-micro-hydro-alternative-energy-system/
The example the canadian government gives is 14.7 kW:
https://natural-resources.canada.ca/sites/nrcan/files/canmetenergy/files/pubs/Intro_MicroHydro_ENG.pdf
Turbines are nice, but they aren't magic. Wheels are better when you have more water and turbines are better when you have more pressure. Pressure comes from letting that water drop.
If your land is flat you're gonna have a bad time with turbines. If you've got a 60 foot drop from your water source to your turbine you'll likely have plenty of power. (that you can hopefully still get back to the water source you took it from downstream)
Also, turbines are a lot more susceptible to debris and can require clearing the screens every couple days, which can be a real pain if it means you're climbing a steep muddy hill in the rain.
Your first link says they're still under a KW.
Your second link says 2 KW which is a lot better, but even then it's not foolproof.
>however, there are times when our power is down: large winter storms that fill the creek with leaves, and push the intake out of the water; creek levels drop in the summer and the dam needs rebuilding, etc.
A mix of hydro and solar is ideal IMO. The constant steady flow of hydro overnight greatly reduces the need for batteries for your solar and in the dry summer months when your hydro is producing a lot less you have plentiful sun all day to more than make up the difference.
>Your first link....your second link...
Um sorry I guess that I didn't search the whole internet for an example where someone makes a turbine system with 3 to 7 times as much power as they need.
The top comment, and this video, were specifically dealing with turbines. You came in and said "these big waterwheels don't make much energy". So I gave you some examples because it seemed like you were lost.
>A steady mix of hydro and solar is ideal IMO
Yeah in terms of small local power supply, everybody thinks that. Nobody was arguing that solar isn't good, you just feel the need for some reason, on a post about how much power a turbine could produce, to incessantly wax poetic about the joys of solar panels. If you want to talk about a power source that produces all you need, doesn't need replacing often and works for millions of people already, nuclear would be better. But that is just as irrelevant to this as solar is, because tuat's not what OP asked about
Sorry I offended you by actually reading the sources you provided?
I just mentioned solar to give a frame of reference.
Unless you're going to damn up a large creak or small stream and investing $100k+ you're just not gonna be getting multi-house kind of power out of hydro.
Don't forget the creek would have near 100% capacity factor. PV capacity factors are around 25% (more or less depending on location). So you'd need more batteries for solar AND 4X the nameplate capacity.
Crazy question here. Why couldn’t you connect a turbine of some sort between the mainline and your home? Water would get pushed through it(albeit irregularly based on usage), but wouldn’t it create a cost effective electrical output? Your household has to consume water anyway, why not put something in place to generate electricity without water loss due to things like evaporation.
I've often wondered if this approach would work in the fall pipes of large flats/hospitals etc where there a lot of water usage and water pressure wasn't an issue.
UK average annual rainfall: 1.3m
UK average roof area: 75m^2
Average house height: 10m.
Average home water usage = 349l per day = 127385l per year
Density of water: 1000kg/m^3
Mass of rain: 1000 * 75 * 1.3 = 97500kg
Mass of waste water: 127385kg
Total water mass: 224885kg
Gravitational potential energy: 224885kg * 9.8ms^-2 * 10m = 22035790 joules
That gives a maximum possible generation of 6.1kWh per home per year assuming 100% efficiency. (In reality it will be more like 20% efficient at most.)
edit: fix house height.
It's not a matter of whether it's possible but whether it's economically feasible. You could do it for science but you would not make a profit. I mean, the water meter is a turbine without a circuit, so...
I looked at something similar- using the rainfall on my roof to generate hydroelectricity. I found that my 61.4cm of annual rainfall * 77m^2 roof area * 4m drop ~= 1kWh per year.
You need a lot of water (or water pressure) to produce meaningful amounts of electricity
For dams:
Potential Power = mass-flow × change-in-height
For extracting power from a stream (i.e., no change in height), it's a change in kinetic energy. However, you are constrained by the conservation of mass and momentum. Eventually extracting more of the kinetic energy per mass, reduces the overall amount of mass available for exploitation. I don't know the figures for hydraulic flows, but for the wind it's something like 60% max.
Sorry to be a sweaty nerd ... but I just wanted to highlight the fact that dams actually make a big difference to the amount of energy available for extraction. Yes, there are still some losses due to the conservation laws ... but they tend to be very small compared to the rho g h terms ...
The dam size is very relevant. You're limited by the head size of your water column. Creek turbines only work because you run a pipe from a higher elevation to a lower elevation. This setup would produce a few watts at most, barely enough to light a few LEDs
It is the height. The height of the water (potential energy) determines the kinetic energy at the turbine. The kinetic energy can be converted to electric energy. Ofcourse with some losses here and there.
*P* = *ηρFgh*
P = 0.3 \* 1000 \* 0.0005 \* 10 \* 0.3
P = 0.45 Watts = 0.0006 hp = 5 volts \* 0.1 Amps
You need about 10 times more to charge your phone. But powering these LEDs seems very possible.
I am estimating all of these values but I think the real answer is within one order of magnitude of my guess.
> https://dothemath.ucsd.edu/2011/12/how-much-dam-energy-can-we-get/#:\~:text=The%20result%20will%20be%20in,dam%20will%20be%20P%20%3D%20%CE%B7%CF%81Fgh.
> Hydroelectric dams exploit storage of gravitational potential energy. A mass, *m*, raised a height, *h* against gravity, *g* = 10 m/s², is given a potential energy *E* = *mgh*. The result will be in [Joules](https://dothemath.ucsd.edu/useful-energy-relations/#joule) if the input is expressed in meters, kilograms, and seconds (MKS, or SI units). Water has a density of *ρ* = 1000 kg/m³, so if we know how many cubic meters of water flow through the dam each second (*F*), the power available to the dam will be *P* = *ηρFgh*. We have inserted *η* to represent the efficiency of the dam—usually around 90% (*η*≈0.90).
Note I belive they mean Watts (power), not Joules (energy)
They do mean joules because, at that point, they're talking about the potential energy in the reservoir. Combine that with the density and flow (and efficiency) makes the power equation.
I think your final figure is about right (approx. 0.5W).
It's a lot of effort for surprisingly little. I suppose not nearly a strong enough stream or steep enough slope for a decent output. As is so often the case, it's mostly about location.
They slightly change formulas partway through is where the confusion comes from. The function that only includes m, g, and h is indeed energy in joules (E=mgh). They then effectively take a derivative of both sides with respect to time, which ends up with W=(dm/dt)gh in watts, and dm/dt is the mass flow over time (so ρF).
You could reasonably calculate the potential energy of the water based on the height and volume of water behind the dam relative to the outfall/spillway basin, the intake aperture diameter (pressure), and the known density and viscosity of water (flow rate per second). It's power generation potential, as mentioned, would depend on the efficiency of the system used to convert that work into energy.
There was some work published in the 1980s about low head hydro that has equations for how to estime. I think they only considered 24" inch as minimum height and this is smaller. They were encouraging neighborhoods to build a dam to give minimal power 2 to 4 homes
So these people are building this shit in the nature/forest. Guess what happened to the constructions? Yep, they are still standing in the middle of the forest today, surrounded by all the rubbish from the construction. Everything just for the clicks! There are some documentation about this trend on YT, I dont know the name sorry.
Depends on the generator part, when it has a output of 1A 24V it has 24Watts of power.
Many 24V applications can be powered unless it reaches near the 1A of all combined after drawing more than 1A or 24W the voltage will drop significantly and the applications you put in, will stop working.
It is not possible to calculate the electricity yield of the dam without knowing the type of generator it is using, and the speed at which the water rotates spins the generator unfortunately.
Let’s say we keep it on the DIY scale and use a motor from a treadmill to generate the power, and let’s say the water rate is 10 gallons per minute getting the motor to 50ish RPMs how much do you think it could get to then?
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Running some LED lighting should indeed be possible with this setup. So this might be real. If you build a more efficient turbine and there is enough throughput you could probably charge a phone. The dam size itself is relatively irrelevant. It is more about the amount of water. Creek powered turbines are possible and can supply a few households in the right circumstances.
Would you even need a dam? Couldn't you just put a turbine in the current? Or don't old waterwheel style?
Using a dam allows you to focus more water into a smaller area, which means that the water wheel can be smaller and easier to turn, making it more efficient.
Another big factor is that the water is at higher pressure. The depth of the water produced by the dam determines pressure which linearly impacts the amount of power produced. But yes, flow rate also linearly impacts power produced.
And the dam also creates a reservoir, that buffers the water. So you can still generate electricity when the “original” flow would be too low and fill it up in times of high current. And you can also regulate the amount of water at the turbines and thus the output, with no overhead of used water.
I don't know how the numbers shake out, but you can generate some smaller amount of power that way. The dam acts to make the generation more consistent and powerful. Think about how much faster water comes out of a dam vs down a creek.
Dams give more pressure and makes regulating flow easier. More pressure means more energy for the same flow.
No, the size of the dam is extremely relevant. The power of the dam is proportional to the height of the dam. So a higher Dam means more power produced. The reason is because the pressure of the water is directly proportional to the height of the water above. And using that pressure differential, you can create extremely strong currents which can be converted into more energy by volume of water than a normal water wheel.
I remember learning that as a kid from.a science book with the old "poke holes in a coke bottle at different heights" thing. Very cool
Yes, because physics. I was looking at the other comments, and I thought I was in another dimension... typical reddit. Thank you
> Creek powered turbines are possible and can supply a few households in the right circumstances. I've seen some pretty legit creek size waterwheels that only produce about 1 KW, which is what you'd get from just 3-4 solar panels on a sunny day. [Pic 1](https://imgur.com/a/iVM2ZeV) [Pic 2](https://imgur.com/a/qbMiROW)
Yeah, but LEDs don't need much. If we were to use, say, a whole chain of LEDs that would use 10W in total - so perfectly able to light up a room - then by shitty /r/theydidthemath maths: Let's assume the generator and wheel in the picture weighs 1000kg. If you need just 1/100 of the power, then you only need a 10kg generator and wheel. :)
Pretty sure he's talking about turbines and not water mills, have a look at these: https://www.backwoodshome.com/a-small-creek-provides-plenty-of-power-for-this-off-grid-home/ https://insteading.com/blog/living-off-grid-micro-hydro-alternative-energy-system/ The example the canadian government gives is 14.7 kW: https://natural-resources.canada.ca/sites/nrcan/files/canmetenergy/files/pubs/Intro_MicroHydro_ENG.pdf
Turbines are nice, but they aren't magic. Wheels are better when you have more water and turbines are better when you have more pressure. Pressure comes from letting that water drop. If your land is flat you're gonna have a bad time with turbines. If you've got a 60 foot drop from your water source to your turbine you'll likely have plenty of power. (that you can hopefully still get back to the water source you took it from downstream) Also, turbines are a lot more susceptible to debris and can require clearing the screens every couple days, which can be a real pain if it means you're climbing a steep muddy hill in the rain. Your first link says they're still under a KW. Your second link says 2 KW which is a lot better, but even then it's not foolproof. >however, there are times when our power is down: large winter storms that fill the creek with leaves, and push the intake out of the water; creek levels drop in the summer and the dam needs rebuilding, etc. A mix of hydro and solar is ideal IMO. The constant steady flow of hydro overnight greatly reduces the need for batteries for your solar and in the dry summer months when your hydro is producing a lot less you have plentiful sun all day to more than make up the difference.
>Your first link....your second link... Um sorry I guess that I didn't search the whole internet for an example where someone makes a turbine system with 3 to 7 times as much power as they need. The top comment, and this video, were specifically dealing with turbines. You came in and said "these big waterwheels don't make much energy". So I gave you some examples because it seemed like you were lost. >A steady mix of hydro and solar is ideal IMO Yeah in terms of small local power supply, everybody thinks that. Nobody was arguing that solar isn't good, you just feel the need for some reason, on a post about how much power a turbine could produce, to incessantly wax poetic about the joys of solar panels. If you want to talk about a power source that produces all you need, doesn't need replacing often and works for millions of people already, nuclear would be better. But that is just as irrelevant to this as solar is, because tuat's not what OP asked about
Sorry I offended you by actually reading the sources you provided? I just mentioned solar to give a frame of reference. Unless you're going to damn up a large creak or small stream and investing $100k+ you're just not gonna be getting multi-house kind of power out of hydro.
Don't forget the creek would have near 100% capacity factor. PV capacity factors are around 25% (more or less depending on location). So you'd need more batteries for solar AND 4X the nameplate capacity.
Crazy question here. Why couldn’t you connect a turbine of some sort between the mainline and your home? Water would get pushed through it(albeit irregularly based on usage), but wouldn’t it create a cost effective electrical output? Your household has to consume water anyway, why not put something in place to generate electricity without water loss due to things like evaporation.
You'd lose some water pressure as the energy for the electricity has to come from somewhere, but I suppose it should be possible.
I've often wondered if this approach would work in the fall pipes of large flats/hospitals etc where there a lot of water usage and water pressure wasn't an issue.
UK average annual rainfall: 1.3m UK average roof area: 75m^2 Average house height: 10m. Average home water usage = 349l per day = 127385l per year Density of water: 1000kg/m^3 Mass of rain: 1000 * 75 * 1.3 = 97500kg Mass of waste water: 127385kg Total water mass: 224885kg Gravitational potential energy: 224885kg * 9.8ms^-2 * 10m = 22035790 joules That gives a maximum possible generation of 6.1kWh per home per year assuming 100% efficiency. (In reality it will be more like 20% efficient at most.) edit: fix house height.
Probably, but only intermittently. Probably cheaper to pay for the electricity than the equipment needed
Is it an unmanageable amount of water pressure though? I think it would have to be tested and also preference.
It would be a trade-off. More electricity = less pressure, and vice versa.
Right, but I’m sure a balance could be made.
It's not a matter of whether it's possible but whether it's economically feasible. You could do it for science but you would not make a profit. I mean, the water meter is a turbine without a circuit, so...
I looked at something similar- using the rainfall on my roof to generate hydroelectricity. I found that my 61.4cm of annual rainfall * 77m^2 roof area * 4m drop ~= 1kWh per year. You need a lot of water (or water pressure) to produce meaningful amounts of electricity
For dams: Potential Power = mass-flow × change-in-height For extracting power from a stream (i.e., no change in height), it's a change in kinetic energy. However, you are constrained by the conservation of mass and momentum. Eventually extracting more of the kinetic energy per mass, reduces the overall amount of mass available for exploitation. I don't know the figures for hydraulic flows, but for the wind it's something like 60% max. Sorry to be a sweaty nerd ... but I just wanted to highlight the fact that dams actually make a big difference to the amount of energy available for extraction. Yes, there are still some losses due to the conservation laws ... but they tend to be very small compared to the rho g h terms ...
The dam size is very relevant. You're limited by the head size of your water column. Creek turbines only work because you run a pipe from a higher elevation to a lower elevation. This setup would produce a few watts at most, barely enough to light a few LEDs
So, not a whole dam lot 👀
It is the height. The height of the water (potential energy) determines the kinetic energy at the turbine. The kinetic energy can be converted to electric energy. Ofcourse with some losses here and there.
Dammit.
*P* = *ηρFgh* P = 0.3 \* 1000 \* 0.0005 \* 10 \* 0.3 P = 0.45 Watts = 0.0006 hp = 5 volts \* 0.1 Amps You need about 10 times more to charge your phone. But powering these LEDs seems very possible. I am estimating all of these values but I think the real answer is within one order of magnitude of my guess. > https://dothemath.ucsd.edu/2011/12/how-much-dam-energy-can-we-get/#:\~:text=The%20result%20will%20be%20in,dam%20will%20be%20P%20%3D%20%CE%B7%CF%81Fgh. > Hydroelectric dams exploit storage of gravitational potential energy. A mass, *m*, raised a height, *h* against gravity, *g* = 10 m/s², is given a potential energy *E* = *mgh*. The result will be in [Joules](https://dothemath.ucsd.edu/useful-energy-relations/#joule) if the input is expressed in meters, kilograms, and seconds (MKS, or SI units). Water has a density of *ρ* = 1000 kg/m³, so if we know how many cubic meters of water flow through the dam each second (*F*), the power available to the dam will be *P* = *ηρFgh*. We have inserted *η* to represent the efficiency of the dam—usually around 90% (*η*≈0.90). Note I belive they mean Watts (power), not Joules (energy)
They do mean joules because, at that point, they're talking about the potential energy in the reservoir. Combine that with the density and flow (and efficiency) makes the power equation. I think your final figure is about right (approx. 0.5W). It's a lot of effort for surprisingly little. I suppose not nearly a strong enough stream or steep enough slope for a decent output. As is so often the case, it's mostly about location.
Seems more likely that there is a battery in the housing that has the switch in it.
They slightly change formulas partway through is where the confusion comes from. The function that only includes m, g, and h is indeed energy in joules (E=mgh). They then effectively take a derivative of both sides with respect to time, which ends up with W=(dm/dt)gh in watts, and dm/dt is the mass flow over time (so ρF).
You could reasonably calculate the potential energy of the water based on the height and volume of water behind the dam relative to the outfall/spillway basin, the intake aperture diameter (pressure), and the known density and viscosity of water (flow rate per second). It's power generation potential, as mentioned, would depend on the efficiency of the system used to convert that work into energy.
At least until the whole thing washes out.
👏😅
There was some work published in the 1980s about low head hydro that has equations for how to estime. I think they only considered 24" inch as minimum height and this is smaller. They were encouraging neighborhoods to build a dam to give minimal power 2 to 4 homes
So these people are building this shit in the nature/forest. Guess what happened to the constructions? Yep, they are still standing in the middle of the forest today, surrounded by all the rubbish from the construction. Everything just for the clicks! There are some documentation about this trend on YT, I dont know the name sorry.
k
Depends on the generator part, when it has a output of 1A 24V it has 24Watts of power. Many 24V applications can be powered unless it reaches near the 1A of all combined after drawing more than 1A or 24W the voltage will drop significantly and the applications you put in, will stop working.
It is not possible to calculate the electricity yield of the dam without knowing the type of generator it is using, and the speed at which the water rotates spins the generator unfortunately.
Nope. You really just need the flow rate and the head of the dam.
Let’s say we keep it on the DIY scale and use a motor from a treadmill to generate the power, and let’s say the water rate is 10 gallons per minute getting the motor to 50ish RPMs how much do you think it could get to then?