Which of the following is an example of the process of cogeneration?

1. Using timber waste products as biofuel

2. Using wastewater from electricity production for heating homes

3. Using corn crops for ethanol fuel production

4. Using the reservoir behind a hydroelectric dam for recreation

Answer:

✅ 2. Using wastewater from electricity production for heating homes

Explanation:

Cogeneration (also called combined heat and power, or CHP) is the process of simultaneously producing electricity and utilizing the excess heat for another purpose, improving overall energy efficiency.

Thus, option 2 best represents cogeneration, where waste heat is reused for heating homes.