BEYOND O&M Shawn Maurer SEDAC Building Specialist Smart Design Assistance Center (SEDAC), University of Illinois at Urbana Champaign
PRESENTATION OVERVIEW and Take away: Regular costs less over the long term!
and MAINTENANCE AND BUILDING ENERGY ~40-50% of building energy and energy costs are from heating, cooling, fans, and pumps and much higher when adding in lighting. Some utility budgets exceed maintenance salaries Building Operator is in control of equipment operation, maintenance, and replacement.
BUILDING ENERGY EXAMPLE Newer School (~200,000 sf) with BAS. Exhaust Fans weren t scheduled. Estimated $7,000 in savings from scheduling off when school was unoccupied. goes beyond fixing broken equipment. is making sure the building systems are running in the best means possible. and
and UTILITY BILLS What are your utility costs or budget? The first step to excellent maintenance is knowing what you are using.
and UTILITY BILLS Usually finance department is in charge of these. Don t be shy to ask for them. You can typically download from the internet if you know account/meter numbers. Why look at these?
and UTILITY BILL EXAMPLE
UTILITY BILLS - TRACKING Many methods for this Spreadsheet Third Party Software Insights (ComEd) Portfolio Manager and
UTILITY BILLS - TRACKING
UTILITY BILLS - TRACKING One step further is to track weather Use Cooling and Heating Degree Days Represent intensity of weather for the day/month/year Available at degreedays.net Use closest weather station Add to spreadsheet 1,600 1,400 1,200 1,000 800 600 400 HDD CDD 200 0 Jul-08 Aug-08 Sep-08 Oct-08 Nov-08 Dec-08 Jan-09 Feb-09 Mar-09 Apr-09 May-09 Jun-09 Jul-09 Aug-09 Sep-09 Oct-09 Nov-09 Dec-09 Jan-10 Feb-10 Mar-10 Apr-10 May-10 Jun-10 and
Utility Bills - Tracking One step further is to track weather Use Cooling and Heating Degree Days Represent intensity of weather for the day/month/year Available at degreedays.net Use closest weather station Add to spreadsheet Utility Bills the Building Certifications
and UTILITY BILLS TRACKING WHY?
and UTILITY USE CASE STUDY Gas Use (therms) 25,000 20,000 15,000 10,000 5,000 Monthly Gas Usage Therms Heating Deg Days HDD line is a relative indicator of gas use Notice pretty good seasonal dependency 0 Feb-07 Aug-07 Feb-08 Aug-08 Feb-09 Aug-09 Feb-10 Aug-10 2,000 1,500 1,000 500 0 Heating Degree Days Electricity (kwh) 300,000 250,000 200,000 150,000 100,000 50,000 Monthly Electricity Usage On-Peak kwh Off-Peak kwh 2008 had summer school Some anomalies in 2007 Fairly high spring and fall baseload 0 Feb-07 Aug-07 Feb-08 Aug-08 Feb-09 Aug-09 Feb-10 Aug-10 500 400 300 200 100 0 Cooling Degree Days
and UTILITY USE CASE STUDY Electricity (kwh) Gas Use (therms) 25,000 20,000 15,000 10,000 5,000 300,000 250,000 200,000 150,000 100,000 50,000 Monthly Gas Usage Therms Heating Deg Days 0 Feb-07 Aug-07 Feb-08 Aug-08 Feb-09 Aug-09 Feb-10 Aug-10 Monthly Electricity Usage On-Peak kwh Off-Peak kwh Cooling Degree Days 0 Feb-07 Aug-07 Feb-08 Aug-08 Feb-09 Aug-09 Feb-10 Aug-10 2,000 1,500 1,000 500 0 500 400 300 200 100 0 Heating Degree Days Then, things go crazy. Cooling Degree Days
and UTILITY BILLS TRACKING BENEFITS Comparing current usage to historic usage may help to notice malfunctioning equipment, equipment off schedule, etc. Better estimating of utility budgets. Verify energy savings projects. May want to investigate submetering or an energy dashboard.
BENCHMARKING Once you know your consumption you can begin to compare to other buildings. Compare on a per foot basis. Usually seen as kbtu per square foot per year Can also compare electricity or natural gas use per square foot. Know how much room there is to improve and
and BENCHMARKING - TOOLS ENERGY STAR s Target Finder Commercial Buildings Consumption Survey (CBECS)
TARGET FINDER Uses similar buildings types in the same areas Input zip code, facility characteristics, and annual energy consumption Receive a score of how you compare If your score is higher than 75 you could qualify as an ENERGY STAR building and
and SCHOOL BENCHMARKING Use Intensity (kbtu/sf/yr) 140 120 100 80 60 40 20 Electric kbtu/sf Gas kbtu/sf 0 2 - HS 4 - Elem 6 - MS 8 - MS 10 - K-8 12 - MS 14 - Elem 16 - Elem 18 - Elem 20 - HS 22 - Elem 24 - HS 26 - HS 28 - Elem 30 - Elem 32 - K-12 34 - Elem 36 - HS 38 - MS 88 - Elem 41 - Elem 43 - HS 45 - HS 47 - Elem 49 - HS 51 - Elem 53 - K-12 55 - Elem 57 - Elem 59 - MS 61 - Dist 63 - Elem 65 - Elem 67 - HS 69 - MS 71 - Elem 73 - HS 75 - MS 77 - Pre-k 79 - Elem 81 - Elem 83 - MS 85 - HS 87 - HS 88 - K-12
and SCHOOL BENCHMARKING New Schools, < 20 years old Use Intensity (kbtu/sf/yr) 140 120 100 80 60 40 20 Electric kbtu/sf Gas kbtu/sf 0 2 - HS 4 - Elem 6 - MS 8 - MS 10 - K-8 12 - MS 14 - Elem 16 - Elem 18 - Elem 20 - HS 22 - Elem 24 - HS 26 - HS 28 - Elem 30 - Elem 32 - K-12 34 - Elem 36 - HS 38 - MS 88 - Elem 41 - Elem 43 - HS 45 - HS 47 - Elem 49 - HS 51 - Elem 53 - K-12 55 - Elem 57 - Elem 59 - MS 61 - Dist 63 - Elem 65 - Elem 67 - HS 69 - MS 71 - Elem 73 - HS 75 - MS 77 - Pre-k 79 - Elem 81 - Elem 83 - MS 85 - HS 87 - HS 88 - K-12
and BENCHMARKING MOTIVATION Comparing current usage to historic usage may help to notice malfunctioning equipment, equipment off schedule. Comparing to other buildings can help quantify your potential for energy savings / reduction.
and PERFORMANCE AND MAINTENANCE Performance of the building is heavily influenced by maintenance.
and VARIOUS MAINTENANCE APPROACHES US DOE s Federal Management Program: Operations and Best Practices: Reactive ( run it until it breaks ) $18/hp Preventative ( follow the schedule ) $13/hp Predictive ( test when to replace ) $9/hp Reliability Centered (hybrid) $6/hp
and COST OF DEFERRED MAINTENANCE Graphic from Stonegate Property Inspections, LLC
ECONOMICS OF MAINTENANCE It is estimated that O&M programs targeting energy efficiency can save 5% to 20% on energy bills without significant capital investment (PECI 1999) Tune-ups typically translate to energy savings of 5% to 15% (E SOURCE) Cost of tune-up (ENERGY STAR) $0.01-$0.10/sf newer bldg $0.10-$0.50/sf older bldg US DoE Forrestal Bldg. Steam trap maintenance program saved $250,000/yr and
and CHILLER TUNE-UPS = 5% OF COOLING COSTS To maintain efficiency in O&M Maintain economizers Test at least twice a year Damper operation Adjust air temperature sensors Clean and replace air filters Inspect and clean evaporator and condenser coils Measure and correct and refrigerant charge Fix leaks in cabinet and supply ducts Reset condenser water temperature Stage multi-chiller operation to improve part-load performance Other: Raise thermostat settings Reduce run hours Reset chilled water temp Clean evaporator and condenser tubes Minimize use of reheat Don t cool unused space
and BOILER TUNE-UPS = 6% GAS SAVINGS To maintain efficiency in O&M Develop and implement routine inspection and maintenance program Check steam traps and lines (replace as necessary) Condensate pumps Boiler tune program once per year Insulate piping and central storage tank Blowdown to remove accumulated dissolved solids Excessive blowdown wastes water, energy, and chemicals Water treatment program to prevent scale and corrosion Clean and inspect boiler water and fire tubes Use expansion tank to temper boiler blowdown drainage Install meters on boiler system make-up lines and recirc water loop Consider summer shutdown
and STEAM TRAP MAINTENANCE 15-30% FAILED To maintain efficiency in O&M Test traps and replace as failed Sight method (visually observe steam escaping) Sound method (ultrasonic measuring equipment) Temperature method (thermography) least reliable Automatic diagnostics (self-diagnosing steam trap) Checklist for possible trap failure Abnormally warm boiler room Condensate received venting steam Condensate pump water seal failing prematurely Boiler operating pressure difficult to maintain Vacuum in return lines difficult to maintain Water hammer in steam lines Higher than normal energy bill Inlet and outlet lines to trap nearly the same temperature
UP NEXT: SHORT BREAK Presentations will be available at: presentations.sedac.org Web site: www.sedac.org Contact: info@sedac.org 1-800-214-7954 Illinois Now 1-800-214-7954 www.ilenergynow.org