21 st Century Cooling for Dry Climates

1. 21st Century Cooling for Dry Climates For the Napa Valley Wine Technical Group Dick Bourne, WCEC Assoc. Director January 22, 2009

2. Electricity: Cooling is the Culprit • July peak demand is 35% above January • Cooling causes electricity peaks • 7% Load Factor for Residential • 22% Load Factor for Non-Residential • Cooling peak reducers - best new peaking plants

3. Western Climates: Issues = Opportunities • Large Diurnal Temperature Swings • Issue – Poor Load Factor • Opportunity – Thermal Storage • Low Outdoor Humidity • Issue – Non-Optimized Equipment • Opportunity – Evaporation for Cooling, Radiant Cooling

4. WCEC: Who We Are • Part of the Energy Efficiency Center at University of California, Davis • Launched April 2007 • Current staff: • Mark Modera, Director • Dick Bourne, Associate Director • Marshall Hunt, Programs Director • Kristin Heinemeier, Senior Engineer • Seven Mechanical Engineering Students

5. WCEC: Who We Are • Affiliate Structure • Utilities • PG&E, SCE, SMUD, SEMPRA • Manufacturers • Delphi, Ice Energy, ICI, Lennox, Munters, NovaTorque, Seeley Intl., Speakman, Thermal Flow, Trane, Viega, VRTX • Contracting/Design Firms • Beutler, Davis Energy Group, Timmons Design Engineers • State Agencies • CEC, DGS • Retailers • Wal-Mart, Target

6. WCEC Goals • By 2030, reduce cooling demand and energy use from 2007 baseline • New buildings • Zero cooling peak demand • 50% reduction in cooling energy use • Existing buildings • 50% reduction in cooling peak demand • 25% reduction in cooling energy use

7. What We Do • Publicize cooling technologies optimized for hot, dry west • Support affiliate alliances and partnerships • Address market impediments (e.g. codes and standards) • Help bridge commercialization “valley of death” • Emerging technology demonstrations • Research and development • Identify, conduct and support key R&D • Technology development • Laboratory and field testing • Modeling and analysis • Outreach activities • Catalog of energy-efficient cooling systems • Website, newsletters, presentations, publications • Education – university and professional

8. Current WCEC Activities • Funded Projects • CEC - PIER Advanced Cooling Support Program • CIEE – State-building technology demonstrations (SDSU and UCSD lab sash project) • BERG – Improving the Cost Effectiveness of Radiant Floor Cooling Systems • SEMPRA- Energy Performance of Hotel Controls (with CLTC) • SMUD –Hybrid OASys Field Test • BERG at LBNL – Exhaust Duct Leakage Diagnosis in Multi-Family Buildings • EPRI – SEER Review, Status and Recommendations • LANEY COLLEGE/NSF – HVAC training • SCE • Water Management for Indirect and Indirect-Direct Evaporative Air Conditioning • Water Use by AquaChill evaporative condenser

9. Current WCEC Activities • Projects in Process • CEC – Three-Year WCEC Research Support • DOE – Development of lab tests for annual savings predictions • SEMPRA/PG&E/SCE – Statewide Initiatives (Evaporative Cooling, Hot Dry AC, Fault Detection/Diagnostics) • Newly-Funded PIER Projects • Radiant Cooling for Residences • Non-Residential Fault Detection Diagnostics

10. Current WCEC Activities • Current Key Activities • Western Cooling Challenge – announced 6/5/08 • Water Initiative – recent ASHRAE presentation • DOE SEER update • Current Technologies of Interest • Building-Integrated Cooling • Swimming-Pool Heating • WicKool • Dedicated Outdoor Air Systems

11. WCEC Technology Portfolio • Most technologies appropriate for new and retrofit • Rooftop units • Evaporative cooling technologies • Hybrid evaporative/vapor-compression equipment • Water-cooled condensers • Swimming-pool-based air conditioners • Thermal distribution performance • Night-sky radiative cooling • Some opportunities unique to new construction: • Low-cost chilled water storage • Radiant floor cooling

12. Example Technology: DualCool • Accessory system for RTUs • Pre-cools condenser and ventilation air • DOES NOT add moisture to indoors • 25-30% energy and demand savings SYSTEM SCHEMATIC A - High quality condenser air pre-cooler B - Pump & copper supply/return piping C - Ventilation air precooling coil D - Controls

13. Example Technology: Roll-Out Radiant Floor • Prior cost $6-7/ft2 • Rollout cost ~$2/ft2 • Full-scale installation at Wal-Mart store

14. Example Technology: Radiant Floor Benefits • Reduces latent cooling and blower energy • Facilitates non-compressor cooling • Projected savings 60-65% • Projected demand reduction 45%+

15. Example Thermal Storage Technology • Residential/Commercial Swimming Pools • Night-time cooling (non-refrigerative) makes pool water available for day-time low-temperature heat rejection • 20-40oF reduction in refrigerant condensing temperature • 20-50% improvement in EER – higher at peak conditions • Rejected heat serves useful function • Eliminates/reduces gas consumption for pool heating

16. WCEC Market Activities • Demonstrations • Integrated retrofits for strip malls • Technology demonstrations on state-owned buildings • Policy and Market Drivers • Western Cooling Challenge • Hot, Dry Air Conditioners • Water Initiative • Water management for evaporative air conditioning • DOE • SEER regional standards • Lab tests for annual savings predictions

17. Target Market: Rooftop Units (RTUs) with 3 – 30 ton capacity (>500-unit production capacity) • RTUs cool 70% of non-residential floor space in the Western US • Target Performance: 40% reduction in energy use and peak electricity demand • Reward Structure: MOUs w CA IOUs and SMUD for incentive programs – Retailer program sponsorship Western Cooling Challenge

18. January 2009 Laboratory testing of WCC entries can begin June 2009 Field testing of WCC entries can begin January 2010 Shipments of WCC-compliant products can begin Western Cooling Challenge: Schedule

19. New Indirect Heat Exchangers Coolerado • Unique multi-stage indirect design • 90%+ effectiveness, balanced flow • 250 cfm per module, 10” high, 20” long, 19” wide • Used in Coolerado & Desert Cool Aire prototypes

20. New Indirect Heat Exchangers HyPak • High-speed production process • 80%+ effective in lab test • Delivered 4.3 tons for 2’ width • Many other applications

21. Example Market Issue: Water Initiative • Impediments to water-based cooling • On-site water use • Equipment maintenance • Successful water-based systems for buildings • Cooling towers • Pressurized domestic water • Pools • Irrigation • Water conservation • Techniques exist • Not optimized for small-scale evaporative cooling

22. Evaporative Cooling: Water Use Metrics • Evaporative Cooling Water Use • Cooling potential = mass of water * heat of vaporization • Potentially as low as 1.37 gallons/ton-hr • Maintenance Water Use • Rule of Thumb: 2/3 evaporation, 1/3 maintenance • Large Impact of Water Quality • Indirect Water Consumption for Electricity Generation • Enormous range of values - 0.1-72 gal/KWh

23. Water Use for Condenser-Air Pre-Cooling • Analysis Technique • Calculate change in EER with respect to condenser air temperature • Relatively linear • 1-2% change per oF • Calculate condenser temperature change per unit of water evaporated • Use EER change to calculate extra cooling delivered for the same electricity consumed

24. Example Market Issue: Water Issue Resolution • Roles for the WCEC • provide “institutional memory” on water issues • water-use yardsticks • access large cadre of water scientists at UCD • pursue water conservation solutions • save rain runoff for cooling • irrigate w/flushed water • night-sky water cooling

25. Wine Industry Opportunities • Evaporative condensing and pre-cooling • Pre-cooled ventilation air (e.g. Fetzer) • Thermal storage (wine is ideal!) • Radiant cooling to reduce blower power (may need desiccants in high humidity areas) • CHP (e.g. Vineyard 29) • Others?

26. WCEC Mission Summary “Partner with stakeholders to identify technologies, conduct research and demonstrations, disseminate information, and implement programs that reduce cooling-system electrical demand and energy consumption in the Western United States.” http://wcec.ucdavis.edu/ Mark Modera mpmodera@ucdavis.edu