An energy audit is a systematic verification and analysis of use of energy. Energy Conservation Act, 2001, defines energy audit as: “The verification, monitoring and analysis of use of energy including submission of technical report containing recommendations for improving energy efficiency with cost benefit analysis and an action plan to reduce energy consumption”.
Objective of Energy Audit: The primary objective of energy audit is to identify processes where energy is used inefficiently or where energy is being wasted. The energy consumption is compared with available 'benchmarks'. Energy audit gives inputs for managing energy use in the organization and also provides basis for planning a more effective usage of energy.
Stages of Energy Audit: Thus Energy Audit can be classified into the following two types:
- Preliminary Energy Audit
- Detailed Energy Audit
Preliminary Energy Audit: Preliminary energy audit is a relatively quick exercise and uses existing or easily obtained data:
- Details of energy consumption in the organization (energy bills).
- Estimate the scope for saving.
- Identify the easiest areas for attention (un-necessary lighting, higher temp setting, leakages etc).
- Identify immediate (especially no-cost/low-cost) improvements/ savings.
- Setup a baseline or ‘reference point’ for energy consumption.
- Identify areas for more detailed study/measurement.
Detailed Energy Audit: A comprehensive audit provides a detailed energy project implementation plan for a facility, since it evaluates all major energy using systems. It is carried out in the three phase:
- Phase I - Pre Audit Phase
- Phase II - Audit Phase
- Phase III - Post Audit Phase
Phase I – Pre Audit Phase.
- Plan and organise for the audit. Walk through audit & informal interview with energy managers, production manager / plant manager.
- Conduct of brief meeting / awareness programme (2-3 hours) with all divisional heads and persons concerned - for building cooperation, orientation and awareness.
Phase II - Audit Phase.
- Primary data gathering: process flow diagram, energy utility diagram, single line diagram, annual energy bills, energy consumption patterns, historical data.
- Conduct survey and monitoring: Motors, A/C, EA set and lighting.
- Conduct of detailed trials / experiments for selected energy guzzlers.
- Analysis of energy use.
- Identification and development of Energy Conservation Opportunities (ECO): Use brainstorming, contact vendors for new/efficient technology.
- Cost benefit analysis: assess technical feasibility, economic viability and prioritization of ECO for implementation.
- Reporting & Presentation to the top management.
Phase III - Post Audit Phase.
- Implementation and follow-up: Assist and implement ECO and monitor the performance. Make action plan and schedule for implementation. Follow-up and do periodic review.
Energy Audit Instruments:
- Tongue Tester
- Load Manager
- Smart Energy Meters
- HT Megger
- LT Megger
- Earth Tester
- Sling Psychrometer
- Lux Meter
- Temperature & Humidity Monitor with RS-232
- Pressure Gauge
- Specific Gravity Meter