Thermal Energy Storage and LEED GOLD

Transcription

1 Thermal Energy Storage and LEED GOLD Mark M. MacCracken, PE, LEED AP, Pte CALMAC Mfg. Corp. Englewood, NJ USA Calmac.com ECOSTOCK

2 Storage is Natural

3 Most common TES System Water Heater (Electric) Assume one low-flow shower ((2.5gpm x 8.33 lb/gal x (110-60)) x 60 minutes/hr / 3,414 Btu/kW = 18.3 kw East Coast of US 100,000,000 people x 25% x 1/12 Hr/shower x 18.3 kw= 38 Gigawatts = CA Electric Peak on Summer day 4.5 kw Heater Gas Water Heater Design Load = 2 Showers at a time 18.3 kw x 2 x 3414 = 124,950 Btus TES has already impacted US infrastructure

4 Utility Load Factors* in the USA Percent Year *Load Factor = Avg. Load Peak Load

5 ASHRAE 90.1 Base Building Non-Storage Electrical Profile k W Cooling Pumps Fans Lighting Base Load Peak Load 2000 kw Avg. Load 1050 kw Total kwh = 28,000/day (Load Factor = 53%)

6 Design 30% better than 90.1 Non-Storage Electrical Profile k W Cooling Pumps Fans Lighting Base Load Peak Load 1500 kw Avg. Load 800 kw Total kwh = 19,200/day (Load Factor = 53%)

7 Off Peak Cooling (OPC) Electrical Profile k W Charging Storage 40% Peak Load Reduction 600 kw Shed Pumps Fans Lighting Base Load Peak Load 900kW Avg. Load 800kW Total kwh = 19,200/day (Load Factor = 88%)

8 Power continue to be less expensive at Night because of Generation Load Factor 4 Buildings x 1 Megawatt = 4 Megawatts 8,000 mw-h h Sold 5 Buildings with 0.8 mw = 4 Megawatts 10,000 mw-h h Sold! The same generator produces 25% more sellable kw-h!

9 3-D Electric Load Profile -- Full Year 4200 ton-hr of Storage Installed 1990

10 Almost like Non-Storage System Control Logic Chiller Based System Closed System Heat Transfer Fluid 75%H 2 0/25%EG So what is Different? Temperature Modulating Valve Storage Tanks

11 1 Bryant Park, New York City Bank of America / Durst Organization ~2.2 Million ft 2 Going for LEED Platinum History Channel Sky Scrapers

12 Thermal Storage Tank Ice-on-Coil Internal Melt Tank Expansion Chamber Insulation Heat Exchanger

13 Coil & Glycol ton Chiller 31 Ice ton On-Peak Load Temperature Control Valve

14 Coil & Glycol ton Chiller 54 Ice 500 ton Load 44 Temperature Control Valve

15 Coil & Glycol ton Chiller 60 Centrifugal Screw Scroll Reciprocating Ice Melted Ice ton Load Temperature Control Valve

16 How do you measure Green? One Metric is. LEED Green Building Rating System

17 LEED TM Credits Sustainable Sites: 14 points Water Efficiency: 5 points Energy* & Atmosphere: 17 points Materials & Resources: 13 points Indoor Environment Quality: 15 points Innovation & Design: 5 points 69 points Materials & Resources Indoor Environmental Quality Energy & Atmosphere *10 Energy Credit are based on ASHRAE 90.1 which is based on Energy COST Reduction Water Efficiency Sustainable Sites

18 William & Flora Hewlett Foundation LEED Gold 35% Energy Cost Reduction (5points)

19 Project Overview

20 Project Overview Lighting System Indirect Natural Lightening Operable Windows with Natural Ventilation PV for 24 hour lights Off Peak Cooling system Section

21 Basic Components (Calculated 90 ~ 100 ton Peak Load) 80 Ton Evaporative Condensing Chiller 1100 Ton-Hrs of Storage

22 Back Pressure Regulating Valve CHILLER P1 V1 V2 Air Handlers ICE STORAGE P2

23 Design Day Off-Peak Cooling System Tons Making Ice-Meeting Load Ice Discharge Chillers Meeting Load Ice Charge ICE CHARGE Installed Chillers Max Capacity CHILLERS ICE DISCHARGE Storage System 80 ton Chiller 1,100 ton-hr Storage Load Reduction 90 ton or ~ 70 kw Time

24 William & Flora Hewlett Foundation Teamwork Owner The Hewlett Foundation Owner s Representative Bennington/Conover & Associates Shell Architect B.H. Bocook Architects Interior Architecture and Design Hawley Peterson & Snyder Architects Landscape Architect The Office of Cheryl Barton Contractor Vance Brown, Inc. Environmental Building Consultant Simon & Associates Building for Sustainability

25 The LEED Bandwagon Incomplete list of groups that mandate, encourage or reward LEED Certification or designs to LEED Criteria Air Force EPA US Army GSA US Navy State Dept. Arizona California Maine Maryland Michigan Missouri New Jersey Oregon New York Pennsylvania Washington Wisconsin Alameda Cty, CA Arlington Cty, VA Cook Cty., IL Dane Cty., WI King Cty., WA San Mateo Cty, CA Arlington, MA Atlanta, GA Austin, TX Berkeley, CA Boulder, CO. Bowie, MD. Chula Vista, CA Dallas, TX Eugene, OR Houston, TX Kansas City, MO Los Angeles, CA Omaha, NE Phoenix, AZ Pleasanton, CA San Diego, CA San Francisco, CA San Jose, CA Santa Monica, CA Seattle, WA Vancouver, BC, Portland, OR and Scottsdale, AZ require LEED Gold on municipal projects

26 Real reasons Off-Peak Cooling is Green: 1. It is much more Energy Efficient to create and deliver a kwh of Electricity at night then during the hot of the day. Research from the California Energy Commission on 2 Cal. Utilities Reports 8 to 34% savings in raw fuel when comparing On and Off Peak Operation! Heat Rates for Base Load Plants ~7,800 Btu/kWh vs. Peaking Plants ~9,400 to 14,00 Btu/kWh 2. The last power plants to come on during peak hours are normally the dirtiest per kw Ashok Gupta (Director of Energy, NRDC) in NYTimes article Peak Shifting results in lower emissions because some of the plants used to meet demand peaks are among the dirtiest in the city New CA Report by Greg Kats The Costs and Financial Benefits of Green Buildings states Peak power in CA is twice as dirty as Off Peak Power.

27 Other Green Issues 1. Safety Factors/Redundancy (Oversizing) Well documented that oversizing chiller plants creates less efficient real world operation. Engineers have to protect their license Storage is the Natural solution

28 Safety Factor and Redundancy Without Oversizing for same Cost Conventional System* ton Chillers Storage System Excess Capacity Storage System Design Day Load ton Chiller 3,500 ton-hr Storage Tons Time * as per GSA Guideline P-100

29 Design Day Off-Peak Cooling System Tons 600 Discharge Storage Chillers Meeting Load Charge Storage Installed Chillers Max Capacity STORAGE DISCHARGE Storage System ton Chillers 3,500 ton-hr Storage 500 ton Load Reduction or ~ 375 kw STORAGE CHARGE CHILLERS (ONLY 500 TONS) Time

30 1400 Capacity on Design Day with One Chiller Failure Storage System Shortfall Storage Storage Chiller Storage System ton Chiller 3,500 ton-hr Storage Tons 600 Conventional ton Chillers Time

31 Costs of Storage What s the Installed Cost of a ton of Chiller Plant? $1000/ton, $1200/ton, $1400/ton $1600/ton, $1800/ton Storage Costs installed ~ $100 to $150 per ton-hr Depending on location, application and design For each 1 ton of chiller you reduce you need about 8 to 9 ton-hrs of storage. Costs are about the same

32 Other Green Issues 1. Safety Factors (Oversizing) Well documented that oversizing chiller plants creates less efficient real world operation. Engineers have to protect their license 2. Efficiency and Water Use Electric Chillers Absorption Chillers

33 Chiller Energy and Water Efficiency Comparison Chiller Type "Site" COP EER KW/Ton Source Energy COP* Site Heat Rejection Factor Water Use Increase Electric Centrifugal Electric Screw or Centrifugal Making Ice ,000 Btu/ton ,400 Btu/ton Electric Scroll ,000 Btu/ton Absorption (Double Effect) Absorption (Single Effect) ,000 Btu/ton ,000 Btu/ton --- 3% 7% 57% 71% *Assumes 33% National Electric Grid Efficiency

34 Thermal Energy Storage and Sustainable Buildings (Ashrae Journal Sept 04) Topics: LEED Why Green Safety Factory Redundancy Back-up Generation

35 16.6/kWh 4.7/kWh 8.2/kWh 4.7/kWh

36 Time Dependent Values August 20 th Units = k-btu/kwh 2.4 x 4 x 10am 11am 12pm 1pm 2pm 3pm 4pm 5pm 6pm 7pm 8pm 9pm pm 11pm 12am 1am 2am 3am 4am 5am 6am 7am 8am 9am

37 The Plaza At PPL Center Allentown, PA Commercial Office, Retail New construction 280,000 sq. feet Project scope: 8-story Urban setting Completed July 2003 Ice Storage 2800 ton-hr Rating: LEED Gold

38 Fossil Ridge HS Poudre School District Ft. Collins, CO LEED Gold 290,000 ft 2 Peak Load 243 Tons Actual Chiller 125 Tons 1280 Ton Hrs Ice Storage

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40 Off-Peak Cooling in over 6000 installations in 35 countries, many installed over 20 years ago

41 Summary Storage is Nature s way to Balance Supply and Demand Engineer s Paradigm must change. Instead of adding 20-30% to estimated Load, reduce by 20-30% and add Storage for Safety at no extra Cost. Cool Storage reduces Operating Costs Load on Grid Impact on Environment Questions?