Which option reduces electrical loads by scheduling device usage?

• A. Drain water heat recovery system
• B. Solar hot water storage
• C. Heat pump
• D. Condensing boiler

Answer: (A)

The key idea here is reducing how much electricity is needed by the hot water system. A drain water heat recovery system does this by capturing heat from wastewater (like shower and sink water) as it drains and using it to preheat incoming cold water. That means the water heater has to do less work to bring the water up to the desired temperature, so the electric energy used for heating water drops. It’s a passive, energy-saving approach that directly lowers electrical demand without requiring extra energy input.

Other options either rely on electricity to run (a heat pump), burn fuel (a condensing boiler), or depend on solar energy with auxiliary power in some configurations (solar hot water storage). While those can reduce electrical loads in some ways, the drain water heat recovery system provides a straightforward, ongoing reduction in the electricity needed for hot water, which is a common and sizable electrical load in homes.