Retrocommissioning for California State Buildings Energy Efficiency ForumSheraton Grand Hotel, Sacramento September 27, 2006
What is Retro-commissioning? Definition: Retro-commissioning (RCx) is a systematic method for investigating how and why an existing building’s systems are operated and maintained the way they are, and identifying ways to improve overall building performance.
Core Elements of Retro-commissioning • Ensure that the building is performing as efficiently and as the owner expects • Recommend and implement measures that improve equipment performance • Verify that the building owner and staff receive • Documentation and assistance to implement improvements • Training on monitoring and maintaining the improvements • Provide documentation and tools to enhance O&M practices
California State Facilities California’s Public Facilities State, Local Government, K-12 Schools and Community Colleges
Building Commissioning Guides • Developed by the California Commissioning Collaborative (CCC) for the CEC • Two documents: • California Commissioning Guide: New Buildings • California Commissioning Guide: Existing Buildings www.cacx.org
California Commissioning Guide: Existing Buildings www.cacx.org Answers the following questions: • What is RCx and why should I use it? • What are the benefits and costs of RCx? • What happens during the RCx process? • Who should be a part of the RCx team? • How can the benefits of RCx persist over time? • How do I get started with a RCxproject?
The Retro-commissioning Process Phases • Planning • Investigation • Implementation • Hand-off Team • Retro-commissioning provider • Building owner or agent • Building manager and staff • System specialists
Common RCx Findings • Variable speed drives that are not working • Controls that are circumvented or set up improperly • Equipment that is running more than necessary or running inefficiently because of improper control • Controls that were never tuned or need to be re-tuned to provide an appropriate response time or to avoid hunting
Retro-commissioning Benefits • Assist owners and managers with long-term planning • Improve system operation beyond preventative maintenance • Improve equipment performance • Increase O&M staff capabilities and expertise • Increase asset value • Energy savings • Improved indoor air quality, comfort, productivity
Retro-commissioning Costs Costs depend on the size, complexity and scope of the project • Total costs $0.13 to $0.45/sqft Simple Payback 0.2 to 2.1 years (LBNL study of 106 RCx projects: “The Cost-Effectiveness of Commercial-Buildings Commissioning”, E. Mills et al.) • Benefits (same study): • Value of Energy Savings $0.11 - $0.72/sqft • Value of Non-Energy Savings $0.10 - $0.45/sqft • California Caveats: • Data is almost 3 yrs old • Only 14 CA buildings in study • Considerable pricing volatility in all A.E.C. areas at present
Retro-commissioning and Regular Maintenance • RCx should become part of regular maintenance • The State will be recommisioning on a 5-year cycle • RCx pays for itself • Over time, in-house RCx capabilities should grow • RCx can separate the easily implemented improvements (in-house) from the capital retrofits require outside experts
RCx Resources • California Commissioning Collaborativewww.cacx.org • For information on the Architectural Revolving Fund (ARF), contact Howard Sacks, DGS Retro-commissioning Unit, (916)376-1794, Howard.Sacks@dgs.ca.gov Norman BourassaCalifornia Energy CommissionPIER - Buildings End-Use Program NJBouras@energy.state.ca.us David BruderSouthern California EdisonDavid.Bruder@sce.com