Energy Audit and Conservation
The Energy Audit abstract to refers the inspection and survey to analyse the energy consumption for energy preservation in a facility and system to reduce the amount of energy input into the system without negatively affecting the existing running loads. Energy Audit in an occupied building helps to reduce energy consumption while maintaining and improving human comfort, health and safety. Beyond simply identifying the sources of energy use, an energy audit seeks to prioritise the energy uses according to the greatest to least cost effective opportunities for energy savings.
Common types/levels of energy audits are distinguished below; generally, four levels of analysis can be outlined according to ASHRAE:
- Level 0 – Bench marking: This first analysis consists in a preliminary Whole Building Energy Use (WBEU) analysis based on the analysis of the historic utility use and costs and the comparison of the performances of the buildings to those of similar buildings. This bench marking of the studied installation allows determining if further analysis is required.
- Level I – Walk-through audit: Preliminary analysis made to assess building energy efficiency to identify not only simple and low-cost improvements but also a list of energy audit conservation measures (ECMs, or energy conservation opportunities, ECOs) to orient the future detailed audit. This inspection is based on visual verification, study of installed equipment and operating data and detailed analysis of recorded energy consumption collected during the bench marking phase.
- Level II – Detailed/General energy audit: Based on the results of the pre-audit, this type of energy audit consists in energy use survey in order to provide a comprehensive analysis of the studied installation, a more detailed analysis of the facility, a breakdown of the energy use and a first quantitative evaluation of the ECOs/ECMs selected to correct the defects or improve the existing installation. This level of analysis can involve advanced on-site measurements and sophisticated computer based simulation tools to evaluate precisely the selected energy retrofits.
- Level III – Investment-Grade audit: Detailed Analysis of Capital-Intensive Modifications focusing on potential costly ECOs requiring rigorous engineering study.
