Power-Pipe Heat Exchanger Reduces Water Heating Costs by 40%

September 4th, 2012 by James Ayre

Word on the street is, the Power-Pipe Drain Water Heat Recovery (DWHR) System created by RenewABILITY Energy could reduce your water heating costs by as much as 40%. By recapturing significant amounts of the heat that is lost with the used hot water, you could see a significant reduction in your bills.

The system is designed to use the outgoing hot water in the drain pipes to preheat the cold water that is headed into the water heater, raising the incoming water temperature as high as 75°F, greatly reducing the energy needed to heat the water.

“Water falling down a vertical drain stack does not run down the middle of the stack, but instead clings to the inside wall of the pipe. In a DWHR application, falling drain water forms a thin film that rapidly imparts its heat to the colder pipe wall. The Power-Pipe® captures much of this heat, then ‘recycles’ it to raise the temperature of incoming cold water.”

Source: TreeHugger
Image Credits: RenewAbilityEnergy

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Tags: energy efficiency water heater, how to cut down on hot water costs, Power-pipe heat exchanger, reduce hot water costs, reduce your monthly bills hog water

About the Author

James Ayre 's background is predominantly in geopolitics and history, but he has an obsessive interest in pretty much everything. After an early life spent in the Imperial Free City of Dortmund, James followed the river Ruhr to Cofbuokheim, where he attended the University of Astnide. And where he also briefly considered entering the coal mining business. He currently writes for a living, on a broad variety of subjects, ranging from science, to politics, to military history, to renewable energy. You can follow his work on Google+.

Apricor

Excellent idea, but there is a problem. The water pre-heated by the heat from the drain water only benefits the user once the hot water tap is opened, so that it can enter the hot water tank. If nobody does that for quite a while, it will cool down again.
Bob_Wallace

As much as 40% under what conditions?

Not when someone takes a leisurely bath. When they pull the plug that water is likely not very hot.

Not from the typical shower. I would imagine a lot of people mix in some cold to make the water ‘not really hot’, then the water is sprayed into the much cooler air before it reaches the drain.

This one, I’d want to see an independent lab give it a good analysis before getting excited.

Tankless water heaters give 27% to 50% energy savings.
yu tube

Nice, passive, no maintenance, SHOULD be low cost(don’t overcharge), don’t see any downside. On slab houses don’t have much vertical runs so may have to settle for horizontal install.
Wait..just visited homepage, company charges $500 for cheapest model, yep if its green we must overcharge the suckers for it.
This is why green doesn’t advance much. Send an example to China and they’ll copy it and ship it to USA for less than $99.