The Greenest Little Schools in the Midwest

Transcription

1 The Greenest Little Schools in the Midwest And what we can do to get there Andy Robinson LEED AP, Energy Engineer Smart Energy Design Assistance Center

2 Overview Introduction A Little About SEDAC The Language of Energy Technologies for Energy Efficiency New Construction Existing Buildings Pedagogy

3 SEDAC Background Funding by IL DCEO in partnership w/ Ameren and ComEd. Managed by UofI School of Architecture Since starting in 2005 SEDAC has completed over 600 Energy Audits with reports. Over 51 million sf of buildings audited 8 million sf of projects currently on the books Have audited a wide variety of building types

4 SEDAC Services No-Cost Energy Audits Private Businesses, Public Buildings 4 Levels of service ~700 reports in 6 years State Retrocommissioning Pilot Public buildings with HVAC problems State New Construction Incentive $0.08/kWh saved over baseline model Up to $2/sf for LEED buildings

5 SEDAC School Audits Have audited 60 schools in Illinois K-12 Higher education Energy savings ranged from 15 70% Average of 29% Some included renewables. Cost savings ranged from % average of 31%. Average savings for K-12 was $48,636.

6 Typical SEDAC L3 Service Varies with project Design Review and/or Site Inspection Computer Modeling Base Case Alternatives with ECRMs Energy Savings Analysis Life Cycle Cost Analysis Final Report with Recommendations

7 Building Codes and Beyond Illinois Energy Conservation Code 2009 ASHRAE International Energy Conservation Code 2009 ASHRAE Standard % less energy than ASHRAE

8 Why save energy? It is cheaper to invest in energy efficiency than pay for energy over the long term Who should get your money? The utilities or your education funds Example: If total annual utilities = $1.6M 10% energy savings = $160,000 Roughly enough to hire three new teachers, buy 300 new computers or purchase 7,000 new textbooks. This is money we can t afford to leave on the table (or in the utility s coffers)!

9 Why is energy wasted? Some problems are invisible Users are not aware of the significance People don t know what to do There is conflicting information Sometimes it s not easy or convenient We don t always remember that many little steps add up to big savings

10 Benchmark (is it a Hog?) Use your energy bills to estimate: $/sf per year (quick and dirty, but use with caution) < $1/sf = good $1 to $2/sf = fair to slightly poor (typical) $2 to $3/sf = probably room for improvement >$3/sf = oink (unless there is a process) kbtu/sf per year More accurate than dollar metric Use TargetFinder

11 Level 2: Bill Results

12 Therms Degree Days kwh Degree Days Level 3: Bill Results 600, , , , , ,000 0 $21,500 Reheat kwh HDD CDD 1,500 1, $ 25,000 Winter heat. Can this be reduced next? 12,000 10,000 8,000 6,000 4,000 2,000 Billed Therms HDD 1,600 1,400 1,200 1, $22,000 Saved with 2 roof insulation 0 0

13 kbtu/sf-yr Level 3: Benchmarking Plug Loads, $6,900, 5% Cooling, $10,502, 7% Lights, $38,400, 25% Kitchen, $4,102, 3% Fans and Pumps, $5,105, 4% Water Heating, $2,796, 2% Annual Consumption Annual Costs Average Unit Cost Electricity 796,719 kwh $ 76,997 56% $ $/kwh Natural Gas 59,038 therms $ 60,023 44% $ $/therm Floor Area 50,000 sf Energy Use Intensity 172 kbtu/sf-yr Electric Use Intensity 16 kwh//sf-yr Total $ 137,020 Energy Cost Intensity Gas Use Intensity $ 2.74 $/sf-yr 1.2 therms/sf-yr Table 1: Estimated Annual Energy Totals, Cost, and Energy Use Intensity Heating (Gas), $78,391, 52% Envelope, $21,549, 14% Infiltration, $28,368, 18% Ventilation, $33,270, 22% Existing building kbtu/sf-yr Package 1 Package 2 ENERGY STAR

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15 1 - MS 2 - Elem 3 - HS 4 - Elem 5 - Elem 6 - MS 7 - HS 8 - K Elem 10 - HS 11 - HS 12 - Elem 13 - Elem 14 - HS 15 - Elem 16 - Elem 17 - HS 18 - HS 19 - Elem 20 - Elem 21 - Elem 22 - HS 23 - K Elem 25 - Elem 26 - Elem 27 - MS 28 - MS 29 - HS 30 - Elem 31 - Elem 32 - Elem 33 - MS 34 - Elem 35 - HS 36 - Elem 37 - Elem 38 - Pre-K 39 - Elem 40 - Elem 41 - MS 42 - HS 43 - Elem 44 - Elem 45 - Elem 46 - HS kbtu/sf-yr $/sf Illinois School Benchmarks (K-12) SEDAC Illinois K-12 School Energy Use Intensities Electric kbtu/sf Gas kbtu/sf $/sf $3.50 $3.00 $ $2.00 $1.50 $1.00 $ $-

16 How Schools Use Energy Building Envelope (Walls, Roof, Windows, Floors) Lighting Heating, Ventilating, and Air Conditioning (HVAC) Internal and Process Loads (cooking, hot water, swimming pools, laboratories, food service, etc.) Typical ECRMs Envelope Insulation and windows Lighting LED exit signs HVAC upgrades

17 Increase Envelope R-Values Insulate Walls to at least R-13 + R-7.5 c.i. Insulate Roofs to at least R- 20, Attics to R-38. Floors over unconditioned spaces to R-30. These are code minimums. Highly Efficient Buildings will have values which exceed these.

18 Window Characteristics Five key parameters: U-Factor Solar Heat Gain Coefficient (SHGC) Visual Light Transmittance (VLT) Air Leakage (cfm/sf) Condensation Resistance

19 Magic Windows? Low-e The e stands for emissivity Absorptivity and Emissivity describe how materials respond to radiation. The properties are wavelength dependent. This allows a material to transmit light but block heat. Gas fill Air Argon Krypton

20 Window Shades and Films Insulating shades Insulating shades are costly but might be a viable retrofit Glare Protection Open to let light in when appropriate (turn lights off) Close at night to hold heat in Low-e films can be added to existing windows Tints don t help save energy

21 Air Sealing Air Sealing is just as important in a school as it is in your home maybe even more! Wind and Stack effects are greater in multi story buildings. Warm air rises, sucking more air in low while it pushes air out high.

22 New vs. Existing HVAC Systems New Options Geo Thermal (Ground Source Heat Pump) Most efficient, most expensive Air Source Heat Pump also possible VAV (Variable Air Volume) With proper controls (and maint.) are very efficient BUT Reheat can cause systems to fight each other Dedicated Outdoor Air with dehumidification is best Existing Options Boilers - Install most efficient Chillers - Need proper maintenance and controls Air Handling - Controls

23 Solutions to VAV Reheat Problems Supply Temperature Reset Saves cooling energy Saves reheat energy Increases hours when economizer can be utilized. Static Pressure Reset Provides significant fan energy savings since system is often at part load Reduces fan noise Static Pressure Reset Demand Control Ventilation (schedule, CO2)

24 Boilers, Chillers, Etc. Chillers Shut down chillers when OA temperatures are consistently below 50, and use economizer. Water Supply Temp Lower boiler water supply temperature in mild weather. Raise chilled water supply temperature in mild or dry weather. Older Equipment Begin to plan for replacement now!

25 Boilers Boilers Don t start boilers until OA temperatures are below 50 consistently. Install modular boilers Install high-efficiency condensing boilers Isolate boilers/piping to eliminate heat losses Consider shutting down boilers used for AC reheat in the summer or resetting the supply water temperature.

26 Demand Control Ventilation A huge energy saving!

27 Programmable Thermostats They work when you use them. Set Heating to 68 F, set-back to at least 60 during unoccupied periods. Let condensation be your guide. Set cooling to 74, set-up to 80 during unoccupied periods. Developing morning recovery schedule based on demand charges or system capacity. Easy to do on systems without reheat. Work with recovery times to determine best fit for your building and system.

28 Motors Replace motors with premium motors rather than rewinding them. Immediate replacement Any new motor should be premium efficiency If used > 8000 hours per year Low efficiency or not reliable >50 hp and has been rewound 3 times At failure Used hours per year Currently in good condition Do not replace Used less than 4000 hours per year Can be rewound

29 Commissioning Commission new buildings Retro- or Re-commission existing buildings UofI has saved 20% of energy use with paybacks less than 1 year on retrocommissioning

30 Lighting Lighting Power Density 1.2W/sf maximum. <1.0W/sf preffered Direct/Indirect lighting helps reduce LPD Combine with daylighting wherever possible Add controls to allow for lower light levels where possible.

31 Low Wattage T8 and T5s T12 planned phase out Magnetic ballasts no longer made. Lamps July 2012 Improved lighting quality Retrofit has energy savings as high as 40 % over standard T8. 28W T8s (actually called 32W). Make sure they are compatible with ballasts. 25W T8s (also 32W) coming on the market T5 Great for new fixtures, harder to retrofit.

32 HID to Fluorescent Retrofit Existing System: 400watt High Pressure Sodium and 400watt Metal Halide. Each fixture uses 460 watts (400 for lamp, 60 for ballast) Retrofit One-for-one replacement 6-lamp fluorescent Each fixture uses 234 watts (lamps and ballast combined) Light levels increase 10-20% Long life Better visibility

33 Street and Parking Lot Lighting Probe Start HID to Pulse Start HID a typical retrofit. Fluorescent Induction, and LEDs making moves into market

34 Occupancy Sensors Use them for: Classrooms Offices Restroom lighting Storage Areas Mechanical Rooms Get creative use for HVAC in individual rooms or zones. Wireless sensors now available.

35 LED Exit Signs Payback is quick Rebates available Very basic lighting energy savings measure Chicago approved Change from incandescent at >28W to LED at <2 W

36 12:00 Manage Plug Loads Personal Occupancy Sensor Know what can be turned off Phantom loads Kill-A-Watt meter Great for classes!

37 Computer Power Management

38 Vending Energy Management Install vending Energy Management systems on all drink and snack vending machines. Rebates are available of $100 per beverage machine and $30 per snack machine (which cost $79 each)

39 Water Savings Measures Saves water and energy costs Domestic Water Faucet Aerators Low Flow Shower Heads Low Flow Water Closets Low Flow Urinals Cooling Systems Reduced cooling loads reduce cooling tower water usage Eliminate once-through cooling systems where possible

40 Lower Water Heater Temperature Set domestic water heater temperature to 120 F. Use gas fired booster heater where higher temp is required. Insulate pipes and tank. ~ 1% savings per degree reduced per 8 hours used

41 Samples of DCEO Incentives Lighting K-12 University Relamp to T8 $11.00 $8.50/lamp Delamp $10.00 $7.50/lamp New T8/T5 fixture $0.60 $0.50/Watt reduced CFLs $ $ /lamp Occupancy Controls $0.16 $0.13/Watt controlled LED exit signs $25.00 $23.00/fixture Custom $0.12 $0.09/kWh saved Cooling $25 + $19 + /ton Must meet all guidelines and specifications

42 Solar PV Example North canopy 2'x5' 220 SF of Panels 2,200 Peak Output kw 36.5 factor of 1,200 (factor of 1,200-1,600/kW typical) 43,824 $/yr $0.10/kWh $4,382 Renewable Energy Credits ($0.04-$0.135/kWh possible) $5,916 Total savings/year $10,299 Initial $6/W (6-8 typical) $219,120 Simple Pay Back (yrs) 21.3 Illinois Clean Energy Community Foundation Grant $9,000 ISBE 50% ($250,000 max) $109,560 State 50% Rebate for Public ($50,000 max) $50,000 30% State Rebate N/A 30% Federal Rebate N/A Federal MACRS tax accelerated depreciation N/A Cost after Rebates $50,560 SPB after rebates (yrs) 4.9

43 No-Cost Strategies Find/assign a Champion Involve the students! Benchmark Schools Free strategies: Turn off lighting Control classroom thermostats Establish a plug load plan Close windows and doors when HVAC is on Establish a recognition program Savings from 10 15%

44 Pedagogical Approach Use as a teaching opportunity Update Curriculum Incorporate into math and science curriculum Develop support from students Create environmental clubs Assign an individual or class to track monthly energy use, chart, and make information available to the school Reward students and staff for saving Apply for ICECF renewable grants Fundraisers for light bulbs, cell phones, and batteries

45 To Apply for SEDAC Assistance Call or, Visit the SEDAC web site at and download an application.

46 To Apply for SEDAC Assistance Call or, Visit the SEDAC web site at and download an application.