Power from the pipes!

[TimG]

Reservoir levels are dictated by the quantity needed to supply the system, not by the amount of pressure required in the mains

This has nothing to do with reservoir levels. Energy is only released when water is released so what matters is the amount of water released from the reservoir. The pressure is maintained by exactly matching the water released to the demand. If you start running a turbine the pressure levels will drop unless you increase the flow which would start wasting energy/water. Edited February 26, 2015 by TimG

[Wilber]

This has nothing to do with reservoir levels. Energy is only released when water is released so what matters is the amount of water released from the reservoir. The pressure is maintained by exactly matching the water released to the demand. If you start running a turbine the pressure levels will drop unless you increase the flow which would start wasting energy/water.

The water quantity reqiured by the comunity and the pressure required to operate it do not go hand in hand, this is about using the difference to generate power. One more time, the purpose of the system is to provide water, not balance energy use.

[TimG]

The water quantity reqiured by the comunity and the pressure required to operate it do not go hand in hand, this is about using the difference to generate power. One more time, the purpose of the system is to provide water, not balance energy use.

Yes they do. If there is no demand the pressure will be fixed. If demand increases the pressure decreases unless water is released. It is basic feedback system. Usage causes pressure to drop which cause water to be released which increases pressure. They are exactly balanced. Edited February 26, 2015 by TimG

[On Guard for Thee]

Yes they do. If there is no demand the pressure will be fixed. If demand increases the pressure decreases unless water is released. It is basic feedback system. Usage causes pressure to drop which cause water to be released which increases pressure. They are exactly balanced.

That makes no sense at all. You dont seem to get that there is never a time there is no demand in a big city. The pressure and volume available is there to address fluctuations in demand. Therefore at times of low demand there is excess energy which is what Portland is taking advantage of.

[Wilber]

Yes they do. If there is no demand the pressure will be fixed. If demand increases the pressure decreases unless water is released. It is basic feedback system. Usage causes pressure to drop which cause water to be released which increases pressure. They are exactly balanced.

I realize that the value of this system will vary with each application but you are saying that all the energy stored in a reservoir is required to move the water to through the system, no exceptions. I say bull pucky.

[Derek 2.0]

Yes they do. If there is no demand the pressure will be fixed. If demand increases the pressure decreases unless water is released. It is basic feedback system. Usage causes pressure to drop which cause water to be released which increases pressure. They are exactly balanced.

Exactly, and is why in ones home, if every fixture is on, pressure will noticeably decrease.......

[Wilber]

Exactly, and is why in ones home, if every fixture is on, pressure will noticeably decrease.......

Yes but main pressure still has to be reduced before it goes into your home's system. It doesn't matter if main pressure is 300 psi or 100 psi, your home only needs 50 psi. One way of reducing that pressure is extracting energy from the flow.

[On Guard for Thee]

If every fixture is on, the pressure drops ad the load is automatically taken off the generators. Is that so hard to comprehend...

[TimG]

Yes but main pressure still has to be reduced before it goes into your home's system. It doesn't matter if main pressure is 300 psi or 100 psi, your home only needs 50 psi. One way of reducing that pressure is extracting energy from the flow.

Nope. High pressure water at low speed can be converted to low pressure water at high speed with no energy loss other than parasitic loses. Works just like electrical transformers. If you "extract" energy you will have to draw more water than you actually need in order to meet the pressure/flow rate requirements. Edited February 26, 2015 by TimG

[TimG]

I realize that the value of this system will vary with each application but you are saying that all the energy stored in a reservoir is required to move the water to through the system, no exceptions.

That is not is what I am saying. I am saying the system only releases the amount of energy required to meet the demand and there is no "excess" to exploit. If demand is low the energy stays in the reservoir. If demand is high more energy is released. Edited February 26, 2015 by TimG

[On Guard for Thee]

That is not is what I am saying. I am saying the system only releases the amount of energy required to meet the demand and there is no "excess" to exploit. If demand is low the energy stays in the reservoir. If demand is high more energy is released.

Nope. The energy is already there. Ad there are excesses built i which can be availed.

[Wilber]

That is not is what I am saying. I am saying the system only releases the amount of energy required to meet the demand and there is no "excess" to exploit. If demand is low the energy stays in the reservoir. If demand is high more energy is released.

And I am saying there is more energy stored in many systems than is required to deliver the water.

[TimG]

And I am saying there is more energy stored in many systems than is required to deliver the water.

But what you say makes no sense because there is no reason to release more energy than necessary to meet the current demand. Lets put it this way: if what you say is true then the energy must be going somewhere today as waste heat. Where is that heat? Remember it would have to be a lot heat if you expect to use it for electricity generation. Edited February 26, 2015 by TimG

[On Guard for Thee]

But what you say makes no sense because there is no reason to release more energy than necessary to meet the current demand. Lets put it this way: if what you say is true then the energy must be going somewhere today as waste heat. Where is that heat? Remember it would have to be a lot heat if you expect to use it for electricity generation.

Here is a simple way of looking at it. Lets say you plan a dinner ad you expect 10 people to be there, you prepare food for that number, but 2 dont show up. You hae extra food to do with what you wish. Same thing happens sometimes when you prepare for everybody to turn on their taps, but a bunch dont for whatever reason. The water flows down those mains constantly.

[Wilber]

But what you say makes no sense because there is no reason to release more energy than necessary to meet the current demand. Lets put it this way: if what you say is true then the energy must be going somewhere today as waste heat. Where is that heat? Remember it would have to be a lot heat if you expect to use it for electricity generation.

So you believe these guys and the city of Portland have no clue what they are doing. OK.

http://www.gizmag.com/portland-lucidpipe-power-system/36130/

[TimG]

So you believe these guys and the city of Portland have no clue what they are doing.

You have to read the fine print. It only works with gravity fed pipelines which means the water being extracted from a natural high elevation reservoir. In this situation there would be excess energy provided by the sun which fills the reservoirs. Nothing in that technology supports your notion that it would be beneficial to use with lines coming from water towers. Edited February 26, 2015 by TimG

[Wilber]

You have to read the fine print. It only works with gravity fed pipelines which means the water being extracted from a natural high elevation reservoir. In this situation there would be excess energy provided by the sun which fills the reservoirs. Nothing in that technology supports your notion that it would be beneficial to use with lines coming from water towers.

Water towers use gravity to feed the system as well. Do you think the water knows how it got into the tower?

[TimG]

Water towers use gravity to feed the system as well. Do you think the water knows how it got into the tower?

The question is whether there could be net energy production. Water towers take power to keep full. You could put these generators on the outflow pipes and they would produce power but you would end up using more power to keep reservoirs full so you would have a net deficit.

BTW: I am being generous by assuming the technology provides a net benefit in the case of natural reservoirs. It could all be a scam by a business seeking to benefit from politicians looking for "green" energy sources. Economic viability is not a requirement when decisions are made based on ideology and marketing literature can be extremely deceptive.

Edited February 26, 2015 by TimG

[Wilber]

The question is whether there could be net energy production. Water towers take power to keep full. You could put these generators on the outflow pipes and they would produce power but you would end up using more power to keep reservoirs full so you would have a net deficit.BTW: I am being generous by assuming the technology provides a net benefit in the case of natural reservoirs. It could all be a scam by a business seeking to benefit from politicians looking for "green" energy sources. Economic viability is not a requirement when decisions are made based on ideology and marketing literature can be extremely deceptive.

The water required to supply the system is the same whether it comes from a natural reservoir or a tower. If you can recover energy from one you can do it from the other. No one is saying anything about net energy production, just recovering more of what has been stored.

Edited February 26, 2015 by Wilber

[TimG]

No one is saying anything about net energy production, just recovering more of what has been stored.

ROTFL. Do you really believe it makes sense to install a system that produces 80kW if that means the energy required to keep the tower full goes from 1000kW to 1100kW?

[Wilber]

ROTFL. Do you really believe it makes sense to install a system that produces 80kW if that means the energy required to keep the tower full goes from 1000kW to 1100kW?

You don't have to add any more bloody water to the tower because the system isn't using any more water. I give up.

[On Guard for Thee]

You don't have to add any more bloody water to the tower because the system isn't using any more water. I give up.

I have too. Some folks just aint good at science and wont learn.

[TimG]

You don't have to add any more bloody water to the tower because the system isn't using any more water.

Yes you do! That is the point I have trying to make. Perpetual motion machines cannot exist. You cannot extract energy without increasing the flow required to maintain pressure. If the flow is larger than it needs to be to supply the demand then it would make more sense save energy by reducing the flow to match the demand. It does not make sense to increase the flow to run turbines. Edited February 26, 2015 by TimG

[Wilber]

Yes you do! That is the point I have trying to make. Perpetual motion machines cannot exist. You cannot extract energy without increasing the flow required to maintain pressure. If the flow is larger than it needs to be to supply the demand then it would make more sense save energy by reducing the flow to match the demand. It does not make sense to increase the flow to run turbines.

The amount of pressure exerted by a column of water is proportional to its weight not its volume. If you filled the reservoir with gasoline it woild exert 20% less pressure even though the volume was the same because it is lighter. Puting an energy recovery tubine in a water line is not going to make people consume more water so why do you need to put more in the reservoir? I don't kniw how many times I have to say this, water systems are designed to deliver water, not balance energy consumption.

[TimG]

The amount of pressure exerted by a column of water is proportional to its weight not its volume.

You are talking about static pressures if there is no motion. The rules change once water starts moving. You need moving water to spin a turbine so you need to ignore what you know about static fluids and learn about dynamic fluids. If you have a turbine extracting energy from the column then pressure drops at the turbine output unless the flow is increased.

uting an energy recovery tubine in a water line is not going to make people consume more water so why do you need to put more in the reservoir?

It is a choice. If you extract energy the pressures will drop. If you don't want the pressure to drop you can release more water and throw it away since no one wants it. I am assuming we agree that the pressure should not drop so that means additional water needs to be removed from the reservoir to prevent the pressure drop. Edited February 26, 2015 by TimG