Certified Energy Auditor Practice Exam

How is boiler efficiency calculated?

1. Heat supplied to boiler divided by heat out of boiler

2. Heat out of boiler divided by heat supplied to boiler

3. Heat input divided by heat output

4. Heat output divided by total expenses

The correct answer is: Heat out of boiler divided by heat supplied to boiler

Boiler efficiency is calculated by taking the heat output from the boiler and dividing it by the heat input supplied to the boiler. This metric gives a clear understanding of how effectively the boiler is converting the fuel energy into useful thermal energy. The heat output is typically measured as the useful energy produced for heating or steam generation, while the heat input includes the energy content of the fuel being consumed. This method of calculation is important because it provides a percentage value that allows for comparison between different boilers or for assessing the performance of a single boiler over time. The closer to 100% the efficiency rating is, the better the boiler is at converting energy without losses. Understanding this calculation is crucial for energy auditors when analyzing the performance of heating systems and recommending improvements to reduce energy consumption and improve efficiency.