You pay to heat the water for your shower, so wouldn't it make sense to milk that energy for all its worth instead of letting it just go down the drain?
That's what Montreal designer David Velan thought. He designed the EcoDrain, a unique patent-pending heat exchanger that transfers heat from hot shower waste water to cold incoming water, therefore cutting water heater usage for showers by 25% to 70%. The result is less energy to produce hot showers, and it could save you $50 to $300 a year...
It's definitely not something you can just install on a Saturday afternoon. It's meant to be installed during construction or remodeling, and it'll cost you $300 - $600.
See more at Ecodrain.
Via The New York Times.