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The cost of heating water

is usually the second-biggest energy expenditure in a multi-unit residential building, exceeded only by the cost of space heating.

As building envelopes become more energy efficient, the cost of water heating grows as a proportion of overall building energy load profiles and costs. Currently, nearly 90% of the heat energy in warm drain water is wasted down the drain. In terms of overall annual energy expenditures, this has a significant impact on a building owner''s budgets. Considering the lifecycle of a building, the cost of this wasted energy is enormous.

The Power-Pipe® Drain Water Heat Recovery (DWHR) System is a proven and effective means to immediately reduce building water heating costs by 20 to 40% and to continue saving throughout the entire building lifecycle.

The Power-Pipe is simple to specify and easy to install. With its exclusive patent-pending design, it is the only heat exchanger that efficiently allows for up to four apartment or condominium units to be plumbed on a single Power-Pipe unit, without a discernible water pressure loss.

Technically known as a falling film heat exchanger, the Power-Pipe is based on a fundamental physical principle called the "falling film" effect. Water falling down a vertical drain stack does not run down the middle of that stack, but instead clings to its inside wall. This creates a thin "falling film" from which the all-copper Power-Pipe can readily recover heat energy.

Built of quality materials and with no moving parts, the Power-Pipe System is simple, effective, foolproof, and maintenance-free, with an expected service life of more than 50 years.

The Power-Pipe's performance has been verified by Natural Resources Canada, the University of Waterloo, as well as other American and Canadian agencies and power companies, in independent third-party testing. The Power-Pipe's proven technology is presently at work in many multi-unit residential projects, including condominiums, apartment buildings, affordable housing developments and university residences.

With its low initial cost and ability to recover up to 40% of the heat energy that is otherwise lost in drain water, the Power-Pipe helps building owners realize an attractive return on their investment, with a full payback typically in 3 to 4 years. In addition, the Power-Pipe qualifies for energy efficiency financial incentives available from numerous governments, as well as many power utility companies.

RenewABILITY Energy Inc. offers free technical support for architects, engineers, developers and building owners, including energy savings studies, feasibility analyses, system design consultations, CAD drawing elements and installation support.

In short, the Power-Pipe:


The Power-Pipe was designed and is manufactured by RenewABILITY Energy Inc. (REI), a developer of cost-effective energy saving solutions for institutional, commercial, industrial and residential customers around the world.


To learn more about Power-Pipe DWHR Systems, or to get started with an installation: