An energy audit is an effective way to identify various energy efficiency (EE) opportunities in residential, commercial, institutional, and industrial facilities. The energy audit determines the most effective energy- and cost-saving measures that can be implemented without adversely affecting the quality of work and the positive environmental aspects of the equipment and processes. A detailed, investment-grade audit (IGA) is the basis for further engineering analysis and design, and investment in EE improvements.
What should you include and consider in an investment-grade audit?
Answer: The IGA contract must describe the scope of work, beginning with a list of facilities that will be included in the project. An accurate IGA can help identify the most cost-effective projects, which will save time and expense when fulfilling project goals. Alternatively, a low-quality audit can create an unrealistic savings analysis, duplication of work in the engineering and design process, and potential problems in performance contract agreements. Because energy audits may become a basis for investment in and establishment of distributed generation facilities, in the present energy market, energy audit work may have significant economic repercussions.
Energy savings performance contract (ESPC) projects, delivered by an energy services company (ESCO), are dependent on IGAs. An ESCO will establish the energy usage baseline, based on the previous 24 to 36 months of utility bills and weather data. After the contract is signed, the savings will be reconciled against the guaranteed values over time. The ESCO will compare actual energy usage to the baseline usage and adjust the baseline to show what the energy use would have been for that year, if that year’s weather had occurred during the base year. Similarly, if occupancy or operating hours have changed, the baseline will need to be adjusted accordingly.
During an audit, the ESCO will perform a detailed investigation of the facilities included in the project. It will record data on all equipment, investigate operating parameters, and establish operating efficiency for the equipment. Also, an ESCO will prepare a complete inventory of all lighting fixtures, including lamp types and wattages, as well as measure power drawn in select locations. Once the ESCO has collected all information, it will develop an energy model for each building. This model will be used to establish the reduction in energy use that is expected to occur when operating more efficient equipment.
Based on the model output, the ESCO will then develop a list of all possible energy conservation measures (ECMs) for each facility, followed by an audit report. The facility owner and the ESCO should review and discuss the audit report and settle on what conservation measures to pursue. Based on the agreed upon measures, the ESCO will develop a complete ESPC proposal, including preliminary installation drawings. Finally, the IGA contract must include a date by which the ESCO will deliver the complete ESPC proposal to the owner.
For additional questions regarding IGAs and ESPCs, please comment to this post or submit a request through the Technical Assistance Center.
Content for this Blog post courtesy of Sentech-SRA/ICF International