Deep retrofits: You get what you pay for Leslie Kramer, Stanford University

1. Deep retrofits: You get what you pay for Leslie Kramer, Stanford University and Jonathan Schoenfeld, kW Engineering June 17, 2014

2. Whole Building Energy Retrofit Program • Deep retrofits in highest energy using buildings on campus • Maximizes energy savings in each building within cost-effectiveness criteria • Looks at a package of measures: no cream skimming • Big payoffs from in-depth energy audit, advanced control strategies, and relentless performance testing.

3. WBERP Process Consulting Engineers Contractors Stanford Team

4. Results • Savings of $3.5 million per year to date • Total cost $14.6 million to date • PG&E rebates of $2 million • Overall simple payback period under 4 years

5. Case Study: Packard • $400,000/year energy cost • 3 stories and a basement • Faculty and grad student offices and dry labs • Built in 2000 • Chilled water, steam and electricity from Stanford’s central plant • 122,500 gross square feet • 4 Air Handlers, 212 VAV boxes • 12 fan coils for additional cooling • VAV boxes controlled by pneumatic thermostats • DDC control of air handlers INITIAL BASELINE CONDITIONS: NOT BAD!

6. Energy Audit Process • ASHRAE Level I • Rough savings estimates • Go/No-Go decision for measure analysis • Level II (Measure Analysis) • Limited trend review • Calibrated eQUEST Model

7. Audit Findings • No-cost Measures • Increase zone setpoints for unoccupied rooms • Schedule how water pumps • Low-cost Measures • Daylighting controls • Eliminate air handler heating coil operation when economizing • Zone Level DDC Conversion • Deadband thermostats • Pressure and Supply Air Temperature Resets • Zone scheduling and override

8. Zone Level DDC Implementation Options • Design-Bid-Build • Develop request for proposal (RFP) for design • Develop design documents • Bid construction • Design-Build • Develop RFP • Bid design-construction • Design-Assist with Performance Specification • Energy consultant develops performance specification • Bid design-construction

9. Performance Specification Development • Input from Multiple Parties • Stanford Facilities Energy Management Team • Stanford Energy Management & Control Systems (EMCS) • ACCO & Sunbelt Controls • kW Engineering • Key Contents: • Equipment specifications • Hardware installation including control hardware locations and wiring pathways • System integration • System architecture & control schematics • Sequence of operations

10. Basis of Energy Savings Supply air temp. (SAT) and duct static pressure (DSP) setpoints Cooling, Heating, Damper Requests Airflows Existing DeltaV Control System SAT & Status Schedule & Setpoints VAV box w/ New DDC controls Existing Air Handling Unit (AHU)

11. Ensuring Persistence of Performance

12. Commissioning Findings (UPDATE Graphic)

13. Verified Energy Savings Figure 3: Relationship between chilled water usage data and CDD

14. Verified Energy Savings Figure 4: Relationship between steam usage data and HDD

15. Verified Energy Savings

16. Efficiency Measures Still Available • Global temperature adjustment • Occupancy based scheduling

17. Take-Aways • Deeper savings require a comprehensive approach • Even relatively new buildings may have out-of-date control systems that are wasting energy • A detailed specification ensures maintenance and energy savings persist • Consider using energy-experts with input from all parties to specify, commission and verify control systems • Private, not-for -profit institution • 8,500 acres • Oldest buildings from 1890s • Santa Clara County is the main jurisdiction • >14 million square feet, 700 buildings • ~$70 million annual utilities spend

18. Thank you for your time! QUESTIONS??