Definition for word: Waste Heat Recovery

A conservation system that utilizes byproduct heat that would otherwise be lost to assist in heating water or a conditioned space. As an example, by utilizing specialized hardware, the waste heat from showering and washing dishes or clothes can be recovered and used to preheat water before it enters a water heating appliance.

Referrence from

A waste heat recovery unit (WHRU) is an energy recovery heat exchanger that recovers heat from hot streams with potential high energy content, such as hot flue gases from a diesel generator or steam from cooling towers or even waste water from different cooling processes such as in steel cooling.

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