Enter the total energy output (J) and the total energy input (J) into the Return on Energy Invested Calculator. The calculator will evaluate and display the Return on Energy Invested.

## Return on Energy Invested Formula

The following formula is used to calculate the Return on Energy Invested.

EROI = EO / EI * 100

• Where EROI is the Return on Energy Invested (%)
• EO is the total energy output (J)
• EI is the total energy input (J)

## How to Calculate Return on Energy Invested?

The following example problems outline how to calculate Return on Energy Invested.

Example Problem #1:

1. First, determine the total energy output (J).
• The total energy output (J) is given as: 175.
2. Next, determine the total energy input (J).
• The total energy input (J) is provided as: 350.
3. Finally, calculate the Return on Energy Invested using the equation above:

EROI = EO / EI * 100

The values given above are inserted into the equation below and the solution is calculated:

EROI = 175 / 350 * 100 = 50 (%)

Example Problem #2:

For this problem, the variables needed are provided below:

total energy output (J) = 600

total energy input (J) = 800

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.

EROI = EO / EI * 100 = ?