The ASHRAE Level 1 audit is walk-through audit that will identify energy efficiency measures (EEMs) while limiting the necessary engineering time and costs to produce the report.  The estimated savings and costs associated with each measure are of rough order magnitude.  The brief report focuses on low-cost and no-cost measures, although capital measures are identified when found.  The report also includes a summary of utility data, the estimation of savings associated with a rate change, the calculation of the energy use index, benchmarking, and targeting.

A small building will use very little energy, and will likely contain very little energy savings potential.  For these small buildings, an ASHRAE Level 1 audit should suffice.  Conducting more advanced audits on these small buildings may not be the most feasible option.

The ASHRAE Level 2 audit is more detailed and requires proficiency and thought to create a quality audit report.  The Level 2 audit includes a complete description of the facility, including an equipment inventory, an energy balance, detailed energy savings and costs associated with each low-cost and not-cost measure, financial analysis of each recommended measure, identification and rough estimates of capital project costs and savings, and a recommended measurement and verification plan for each recommended measure.

The Level 2 audit is the most likely type of energy audit for larger buildings.  The Level 2 audit balances the need for engineering rigor with the need to keep auditing cost effective.  The additional accuracy afforded by the Level 3 audit may not be worth the additional cost.

ASHRAE Level 3 audits are designed to provide additional engineering rigor for more expensive capital projects where risk is less tolerated.  In these audits, trend logs and data loggers are used to better understand how the buildings react to changes in ambient conditions and occupancy.  Calculations for HVAC measures are done with hourly simulations.  Detailed costing estimates are provided, as are life cycle cost assessments.  Typically a scope of work and schematics are provided with the audit so that the contractors installing the measures understand exactly what is to be installed. The reports contain more detailed descriptions of the measures.

Level 3 audits are sometimes called Investment Grade Audits (or IGAs).  These audits are typically done as part of a performance contract.

We investigate and quantify energy savings potential in: