Energy audits play a crucial role in identifying opportunities for energy efficiency improvements in buildings. The audit process is comprehensive and iterative, typically involving several tasks tailored to the specific type and function of the building being assessed. While the sequence of tasks may vary, a general procedure can be outlined to guide the audit process.
Step 1: Building and Utility Data Analysis
This initial step focuses on gathering and analyzing data related to the building's energy systems and usage patterns. Key tasks include:
• Collecting at least three years of utility data to identify historical energy usage patterns.
• Identifying the types of fuel used (e.g., electricity, natural gas, oil) to determine the primary sources of energy consumption.
• Analyzing fuel usage patterns to identify peak demand periods.
• Understanding the utility rate structure, including energy and demand rates, to assess potential cost-saving opportunities.
• Analyzing the impact of weather on energy consumption.
• Conducting a utility energy use analysis based on building type and size to benchmark energy performance.
Step 2: Walk-Through Survey
This step involves a physical inspection of the building to identify potential energy-saving measures. Tasks include:
• Identifying and addressing customer concerns and specific needs.
• Reviewing current operating and maintenance procedures to identify areas for improvement.
• Assessing the operating conditions of major energy-consuming equipment such as lighting, HVAC systems, and motors.
• Estimating occupancy patterns, equipment usage, and lighting requirements to determine energy use density and operating hours.
Step 3: Baseline for Building Energy Use
The objective of this step is to develop a baseline model that accurately represents the existing energy usage and operating conditions of the building. Tasks include:
• Obtaining and reviewing architectural, mechanical, electrical, and control drawings to understand the building's infrastructure.
• Inspecting, testing, and evaluating building equipment for efficiency, performance, and reliability.
• Obtaining occupancy and operating schedules for equipment, including lighting and HVAC systems.
• Developing a baseline model for building energy use.
• Calibrating the baseline model using utility data and/or metered data to ensure accuracy.
Step 4: Evaluation of Energy-Saving Measures
In this final step, potential energy-saving measures are evaluated based on their feasibility and cost-effectiveness. Tasks include:
• Compiling a comprehensive list of energy conservation measures based on findings from the walk-through survey.
• Estimating energy savings resulting from each measure using the baseline energy use simulation model developed in Step 3.
• Determining the initial costs associated with implementing each energy conservation measure.
• Conducting cost-effectiveness analysis using methods such as simple payback or life-cycle cost analysis.
In summary, energy audits involve a systematic approach to assessing energy usage, identifying inefficiencies, and recommending cost-effective measures to improve overall energy performance. The iterative nature of the audit process allows for continuous refinement and optimization of energy management strategies.