Waste-Heat Recovery systems can be adapted to air conditioning systems to provide

• A. Water heating.
• B. Space cooling only.
• C. Electric power generation.
• D. Lighting.

Answer: (A)

Waste-Heat Recovery in air conditioning uses heat that would otherwise be discharged and puts it to work. In many systems, the hot condenser or exhaust heat is routed through a heat exchanger to heat water for domestic or building use. This directly provides a practical service—water heating—so it offers a clear energy-saving benefit by offsetting the need for a separate water heater. The other options don’t fit because lighting isn’t driven by recovered heat, electric power generation would require a different conversion setup not usually part of a standard AC heat-recovery retrofit, and space cooling is the job of the air conditioning system itself rather than a product of the recovered heat.