Harness the Energy of Your Shower Drain-Water

Did you know water heating is the second mostthe effects are dramatic. In a typical home, the
costly energy demand in homes, accounting forDWHR unit can easily raise the cold water
20% to 30% of total household energytemperature from 50° F to 77° F (10° C to
consumption? Or, that 90% of the energy used25° C) – thus saving you energy, time and
to heat water goes down the shower drain?money.
Good news: By installing a Drain Water HeatOther general highlights of non-storage DWHR
Recovery (DWHR) system at home, you cansystems may include:
recycle about 60% of the energy that would- Easy to install or retrofit in almost any home by
otherwise be wasted, and reduce your watermost “Do-It-Yourselfers” or plumbers
heating bills by 25% to 40% – and that's- May be used with tank, tankless, or solar water
without forcing you to alter your lifestyle!heaters
(NOTE: There are two main types of DWHR- Prevents hot water from running out
systems: storage-type and non-storage type. This- Causes no noticeable water pressure loss
article discusses the merits of non-storage DWHR- Provides perfectly save to drink water
units.)- Requires little to no maintenance, and comes
Non-storage DWHR units (e.g., copper heatwith long-term warranty
exchangers made up of two or more copper coils- May be used to harness the energy from cold
tightly wrapped around an inner copper pipe), forto “pre-cool” water or other liquids in
example, work by replacing part of your existingindustrial, commercial, or institutional settings
vertical shower drainage pipe. As you take aDWHR material and installation costs may vary
shower, the heat from the outgoing drain waterdepending on the size and length you need. Some
clings to the inner copper pipe wall and transfersDWHR units, for example, cost between $600
its heat to the incoming cold, freshwater in theand $1,000. Given the return on investment is
outer copper coils (i.e., “pre-heating” the15% to 50% per year (i.e., 2- to 5-year payback
water supply for the water heater).period), however, that is a relatively small
Since copper is an excellent conductor of heat,investment for 20+ years of savings.