Electrical Energy Audit of Buildings
By Bharat Yadav
Energy cost is one of the significant contributors of production cost for most of the Industries and Buildings. Hence, reduction in energy consumption electrical, thermal or in any other form always helps in business sustenance and growth.
Electrical Energy is most common form of energy used in all walks of life including most Plants and Buildings. One of the measures of Sustainability is Specific Energy Consumption.
The need for Energy Conservation through Energy Management Systems and energy audit is gaining further importance with increasing energy cost.
Energy Conservation Measures (ECM) are to be identified and implemented such that it should not impact: Safety, Power Quality, Product Quality, Productivity and Statutory compliance.
Audit of Electrical system covers aspects such as:
- Lighting (including adequacy)
- Air Conditioning (including adequacy)
- Power Quality (including Power Factor and harmonics)
- Safety/statutory compliance
- Applicable Codal compliance such as Building Code and Energy Conservation Code
- O&M aspects
- Cost Benefit Analysis for recommendation
Following activities are typically included for Buildings:
- Measurement of illumination levels
- Measurement of Electrical Parameters for Lighting System
- Measurement of Electrical Parameters for HVAC system (For Fans, Compressors, Total)
- Measurement of Electrical Parameters such as Voltage, Current, kVA, kVAr, THDv, THDi, Current harmonics for Capacitor Banks and non-linear loads such as UPS
- Analysis of Current Harmonics for feeders with high harmonic content
- Measurement of Temperature and RH
- Area wise HVAC calculations are done based on Temperature, RH, room size, equipment load, lighting load, occupancy and compared with details of existing Air-conditioning equipment
- Visual observations during walk through of the facility for safety related observations.
- Cost Benefit Analysis for activities involving CapEx such as Luminaire replacement and circuit regrouping
Lighting System Energy Management Options (LEMOs) include:
- Verifying illumination levels as per applicable standards
- Suggesting energy efficient lighting system components such as luminaire (lamp as well as controlgear/drivers)
- Appropriate lighting controls to be incorporated based on usage and cost-benefit analysis
- Luminaire relocation to avoid shadows and ensure better illumination
- Need based illumination control in unmanned technical areas
- O&M measures including housekeeping
- Lighting circuit regrouping to reduce replacement cost, lighting heat load and reduced load on Air Conditioning (& Maximum Demand)
Few Air-Conditioning aspects to be addressed include:
- Ensuring adequacy and effectiveness of cooling
- Air quality including Fresh air intake
- Fire Barriers and dampers for safety while ensuring proper air conditioning
- Air Distribution system modification for proper Air balancing
Electrical System related aspects include:
- Suggestions for Power Quality improvement (including Harmonics)
- Significance of harmonics interference with communication equipment
- Thermal imaging for identifying hot spots with possibility of safety risks, increased losses and increased maintenance
- Safety Measures for Electrical Installation
TCE already has a wealth of knowledge and experience in conceptualizing and designing Buildings related MEP systems both in domestic and in international arena for varying system sizes and industries to review the Audit findings in line with best equipment, system, technology, Instrumentation, measurement, commissioning and maintenance practices.
TCE has been conducting energy audits/steam audits for various Plants and buildings since 1985 even before it was mandated by statute. The segments include oil refinery, telecom, buildings, Pulp & Paper plants, Exhibition complex, Tyre, Power Plant, Synthetic fibre, Petroleum Coke; Automotive components related Foundry, Match factory, Water network for Towns and City Municipal Corporations.
Sustainability aspect is also taken care by TCE subsidiary EcoFirst.