Which statement about EROI interpretation is true?

Which statement about EROI interpretation is true?

• A. EROI equals energy invested divided by usable energy obtained.
• B. EROI equals usable energy obtained divided by energy invested; higher values indicate more favorable energy sources.
• C. EROI measures only the environmental impact.
• D. EROI must always be less than 1 for viable energy sources.

Answer: (B)

ER OI is the ratio of energy you get back from a source to the energy you had to invest to obtain it. It’s calculated by dividing the usable energy obtained by the energy invested, so a larger number means more energy is produced per unit of energy spent. This is why higher EROI values indicate a more favorable energy source—the more energy you recover for each unit you spend, the more efficient the overall energy process is. It’s not a measure of environmental impact, and viable energy sources must have an EROI greater than 1, since you need to produce more energy than you put in.

ER OI is the ratio of energy you get back from a source to the energy you had to invest to obtain it. It’s calculated by dividing the usable energy obtained by the energy invested, so a larger number means more energy is produced per unit of energy spent. This is why higher EROI values indicate a more favorable energy source—the more energy you recover for each unit you spend, the more efficient the overall energy process is. It’s not a measure of environmental impact, and viable energy sources must have an EROI greater than 1, since you need to produce more energy than you put in.