ERG provides comprehensive commissioning (Cx), retro-commissioning (RCx), and monitoring-based (MBCx) commissioning services for buildings with automated HVAC control systems (Building Automation Systems or BAS).

Typically, these are existing buildings larger than 50,000 square feet, and the retro-commissioning study results in recommendations that have paybacks of less than 18 months. Retro-commissioning is recommended by ASHRAE on either a periodic basis or as an ongoing process (monitoring based commissioning), because modifications to building spaces and controls can significantly degrade even the best building’s energy performance over time. Studies have shown that retro-commissioning saves between 8-40+% of a building’s energy usage. ERG typically sees savings of more than 20%.

ERG’s commissioning process also includes a re-validation of building loads which can lead to significant capital savings when replacing equipment at life-cycle. Our RCx studies often identify investment opportunities that have longer payback periods than the 18-months of a retro-commissioning effort. These measures qualify for “custom audit” incentives.

ERG is a qualified partner for both Ameren Missouri’s and Ameren Illinois’ Retro-commissioning programs. Incentives from Ameren can often reduce costs for a retro-commissioning project to less than one-year paybacks. In some cases, the payback periods for the RCx study and implementation can be as short as a couple of months.