Water heat recycling
Water heat recycling (also known as drain water heat recovery, greywater heat recovery, or sometimes shower water heat recovery) is the use of a energy recovery heat exchanger technology to recover and reuse hot water heat from various activities such as dishwashing, clothes washing and especially showers. The technology is used to reduce primary energy consumption for domestic water heating. Standard units save up to 60% of the heat energy that is otherwise lost down the drain when using the shower.
The technology is fully recognized in Canada where the federal ecoENERGY retrofit for homes program offers grants for installations and the EnerGuide for New Houses program has energy savings and energy credit calculations that it uses for new home construction.
The retail price for a domestic drain water heat recovery unit ranges from around $500 to $1,000. [1] For a regular household, water heating is the second highest source of energy demand. The savings in energy results in an average payback time for the initial investment of 2-10 years. [2]
See also
- Heat recovery ventilation
- Green building
- Renewable heat
- Zero energy building
- Low-energy building
- Pinch analysis