Not all energy audits are created equal. The term “energy audit” gets thrown around loosely, but there are actually distinct levels of assessment, each with a different scope, cost, and level of detail. Here is a breakdown of what each type involves and when it makes sense.
Virtual or Remote Energy Audit
A virtual audit uses your building’s existing data (utility bills, meter readings, BAS data) to diagnose issues without anyone visiting the site. This is a great starting point because it can identify red flags, unusual consumption patterns, and areas worth investigating before committing to an on-site visit.
Virtual audits are especially useful for:
- Portfolio owners screening multiple buildings to prioritize which ones need attention
- Buildings in remote locations where site visits are expensive
- Getting a quick initial assessment before deciding on a deeper audit
At Alert Energy, we often start with a virtual audit to guide the scope of any follow-up on-site work. This saves our clients time and money by focusing on-site efforts where they will have the most impact.
ASHRAE Level I: Walk-Through Analysis
A Level I audit involves a brief on-site visit combined with a review of utility bills and building characteristics. The goal is to identify low-cost and no-cost energy saving opportunities and to flag areas that warrant deeper investigation.
What you get:
- A summary of your building’s energy use patterns
- Identification of obvious inefficiencies
- Rough estimates of potential savings
- Recommendations for operational improvements
A Level I audit is typically done in a single day and produces a concise report. It is a good fit if you want a quick health check on your building without a major investment.
ASHRAE Level II: Energy Survey and Analysis
A Level II audit is more detailed. It includes everything in a Level I plus a deeper analysis of specific systems (HVAC, lighting, envelope, controls) with calculated savings estimates and payback periods for each recommendation.
What you get:
- Detailed analysis of major building systems
- Specific energy conservation measures (ECMs) with cost estimates
- Financial analysis including payback period and ROI for each measure
- Prioritized list of recommended improvements
This is the most common audit level for commercial buildings considering capital improvements. It provides enough detail to make informed investment decisions.
ASHRAE Level III: Detailed Analysis of Capital-Intensive Modifications
A Level III audit focuses on specific, high-cost measures identified in a Level II audit. It involves detailed engineering analysis, energy modeling, and sometimes sub-metering to precisely quantify savings potential.
This level is typically reserved for:
- Major mechanical system replacements
- Building envelope upgrades
- Projects requiring detailed financial justification for investors or lenders
Which level does your building need?
The right level depends on your goals:
- Just need a quick check? Start with a virtual audit or Level I.
- Planning upgrades and need to justify the budget? Level II gives you the financial analysis.
- Considering a major capital project? Level III provides the engineering detail.
We often recommend starting with a virtual audit and moving to deeper levels only where the data points to real opportunities. This keeps costs proportional to potential savings.