--- title: "Execution phase of energy audit" subject: "Industrial Power Distribution and Illumination" chapter: 10 key: "semester_6/industrial_power_distribution_and_illumination:energy-audit-execution-phase" source: https://www.bctengineer.com/q/semester_6/industrial_power_distribution_and_illumination/energy-audit-execution-phase site: BCT Engineering --- # Execution phase of energy audit Industrial Power Distribution and Illumination · Chapter 10: Electrical Energy Audit in Industry - Asked in: 2078 Chaitra, 4 marks - Video: [Energy Audit - Need for Energy Audit - Types of Energy Audit](https://www.youtube.com/watch?v=OsJ-j1LHTHk) — Energy Insight Hub (EIH) - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_6/industrial_power_distribution_and_illumination/energy-audit-execution-phase - Whole chapter: https://www.bctengineer.com/md/semester_6/industrial_power_distribution_and_illumination/chapter-10 ## Question Explain the execution phase of Energy Audit. ## Short answer In the execution phase, detailed surveys and portable measurements are performed on processes, utilities and distribution. Data are analyzed for load profiles, losses and specific energy consumption, then energy conservation opportunities are identified and evaluated techno-economically. ## Answer The **execution (audit) phase** is the main working stage of an energy audit, where measurements are taken and energy-saving opportunities are found, after the pre-audit planning. #### Steps in the execution phase 1. **Detailed survey of each section:** process, utilities (boilers, compressors, pumps, HVAC, lighting) and electrical distribution. 2. **Measurements with portable instruments:** power analyser (kW, kVA, pf, harmonics, load profile), clamp-on meters, lux meter, thermal imager, flue gas analyser, tachometer, flow, pressure and temperature meters. 3. **Data analysis:** load profiles, maximum demand, power factor, transformer and motor loading, losses. 4. **Energy and material balance:** quantify how much energy each area uses and how much is lost. 5. **Specific energy consumption** (e.g. kWh/ton) compared with benchmarks and past data. 6. **Identify energy conservation opportunities (ECOs):** pf correction, efficient motors, VFDs, lighting retrofits, air leak repair, insulation, heat recovery, load shifting. 7. **Techno-economic evaluation:** estimate savings, investment, payback period, NPV/IRR; rank as no-cost, low-cost and high-cost measures. 8. **Discussion with plant staff** to check that recommendations are practical and safe. The output of this phase feeds the **post-audit phase** (report, implementation and monitoring). ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. What is the execution (audit) phase mainly for? A. Forming the team and setting the budget B. Taking measurements and finding energy-saving opportunities C. Presenting the final report D. Monitoring savings after implementation Answer: B. It is the working stage where data are measured and ECOs identified, after pre-audit planning. (Key point: Phase purpose) 2. Which instrument records kW, kVA, pf, harmonics and load profile? A. Lux meter B. Flue gas analyser C. Tachometer D. Power analyser Answer: D. A power analyser measures the electrical parameters and load profile. (Key point: Instruments) 3. What is done in the techno-economic evaluation step? A. Estimate savings, investment, payback, NPV/IRR and rank measures as no-cost, low-cost or high-cost B. Measure lux levels C. Hold the first meeting with management D. Collect last year's bills Answer: A. ECOs are costed and ranked so management can decide. (Key point: Techno-economic evaluation) 4. Where does the output of the execution phase go? A. Back to pre-audit B. Into the post-audit phase for the report, implementation and monitoring C. Directly into plant production D. Nowhere; it is discarded Answer: B. Results feed the post-audit report and implementation. (Key point: Output of phase) ## Related in Industrial Power Distribution and Illumination - [Need of energy audit and technique](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_power_distribution_and_illumination%3Aenergy-audit-need-technique) — Industrial Power Distribution and Illumination, chapter 10, asked 3× - [Energy audit definition and process](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_power_distribution_and_illumination%3Adefine-energy-audit-process) — Industrial Power Distribution and Illumination, chapter 10 - [Energy audit technique and saving opportunities](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_power_distribution_and_illumination%3Aenergy-audit-technique-opportunities) — Industrial Power Distribution and Illumination, chapter 10 ## Related in other subjects - [Energy audit types and audit procedure](https://www.bctengineer.com/question.md?key=semester_6%2Fenergy_resources%3Aenergy-audit-types-procedure) — Energy Resources, chapter 9 - [Energy audit instruments and energy balance](https://www.bctengineer.com/question.md?key=semester_6%2Fenergy_resources%3Aenergy-audit-instruments-measurements) — Energy Resources, chapter 9 - [Preparing and presenting an energy audit report](https://www.bctengineer.com/question.md?key=semester_6%2Fenergy_resources%3Aenergy-audit-report-preparation-presentation) — Energy Resources, chapter 9 - [Energy saving calculation: lighting and motor](https://www.bctengineer.com/question.md?key=semester_6%2Fenergy_resources%3Alighting-motor-energy-saving-case) — Energy Resources, chapter 9