Stop Washing Valuable Energy Down the Drain

Ever wondered which renewable energy source has the quickest payback? Hint: It may be coming from your shower. Or toilet.

But first, a question: Did you take a shower today?

If so, you engaged in an activity that tosses 80 to 90 percent of the energy used to heat the water down the drain. Water heating is among the most energy intensive activities in most homes, and near the top most expensive as well.

For most people, it doesn’t even occur to them that there might be something to do about wasted energy from their morning shower, aside from reducing the amount of water used via a low-flow shower head. Other options available have typically meant fairly complex installations in limited locations -- too many barriers for all but the most motivated people.

Montreal, Canada-based Ecodrain has created a simple solution to the problem: Reuse the heat of the drain water, transferring it back to the water heater, with no mingling of clean and gray water.  Up to 45 percent of the heat is recovered. Water flow is optimized for maximum heat distribution, yet the system has no moving parts, so maintenance is greatly simplified. More than 4,700 iterations in the making, the system -- also called Ecodrain -- is designed to maximize utility while minimizing installation effort and eliminating clogs.

This quick, cheeky explainer video makes the case for heat exchangers entertainingly.

Where Ecodrain excels is in giving people the ability to make an environmentally beneficial choice while saving money, without needing to change their lifestyle or behavior. Such options are key to a broader section of the population making more choices like these.

The potential impact is substantial, and the payoff rapid (17 to 43 percent annually). For one person taking a 10-minute shower daily, Ecodrain saves the annual equivalent of:

• The CO2 emissions of 98.9 gallons of gas


• The greenhouse gas emissions of 728 pounds of waste sent to the dump rather than recycled


• The carbon sequestered in 22.6 tree seedlings grown for 10 years

Beyond the shower and into broader applications

While it’s most known for its home-related uses, Ecodrain is proving malleable to a range of commercial and industrial applications, creating reuse opportunities in unexpected places. Office air conditioning using the toilet, for instance. As Ecodrain puts it:

"Office buildings typically use a lot of cold water for bathrooms. Office buildings also use a lot of air conditioning in the summer. Since heat always naturally travels from hot to cold, air conditioners consume a lot of energy because they pump hot inside air into the even hotter outside air, against its natural tendencies.

"A more natural way to cool is to transfer heat from the hot air into cooler water. Cooling air using fresh water is not allowed in most buildings because it wastes water. However, cool drain water can provide the same low-cost cooling, without wasting any water."

Given that a typical office building uses more than 25 percent of its water supply for cooling towers, according to the EPA, the potential impact is significant. Factor in the fact that California, Texas and Florida are among the biggest users of air conditioning while also facing serious, persistent drought, pursuing options to minimize water use is a must.

When put to use in industrial settings like the Hopital de Rivière Rouge in Quebec, the impact is substantially amplified beyond that of personal-scale installations. Reusing their laundry water heat on one machine will means an estimated 768 times the energy and cost saving potential, as compared to private home use.

While solar and wind may have a higher profile in the renewable energy world, heat exchangers such as Ecodrain offer reliable, substantial, immediate and cost-effective benefits on resource uses ripe for optimization.

Readers: Where has your business been finding unexpected ways to better use its resources? Have you used heat exchangers in your operations? In what way? Tell us about it in the comments section. 

Image courtesy of Ecodrain

Paul Smith is a sustainable business innovator, global trend tracker, the founder of GreenSmith Consulting, and has an MBA in Sustainable Management from Presidio Graduate School in San Francisco. He creates interest in, conversations about, and business for green (and greening) companies, via social media marketing, including Ecodrain.