Water heat recycling

An in-house greywater recycling tank holds 150–175 litres allowing for the majority of waste water to be stored.

[citation needed] Heating water accounts for 18% of the average household utility bill.

Typical retail price for a domestic drain water heat recovery unit ranges from around $400 to $1,000 Canadian.

[citation needed] A 2-year independent study of waste water heat recovery systems installed into residential houses in the UK found savings of 380kWh and 500kWh per person per year.

This reduces the required increase in temperature of the water before it can be supplied to the end user, and therefore lowering boiler fuel burn.