1. Prepared for Enterprise Community Partners Special thanks to New Ecology, Homeowners Rehab Inc. & Performance Systems Development

2. Learning Objectives • Identify 2 reasons to track energy use • Identify heating and cooling “benchmark” energy targets • Identify key information needed to track energy use

3. Why Measure Energy & Water Use? • How much energy do we use ? • Understand our carbon footprint? • To compare energy usage between buildings? • To target improvements to reduce operating expenses? • To inform capital needs and renovation plans? • What else?

4. NYC Portfolio Benchmarking Shows Variability BTU/SF/HDD

5. Who Tracks Energy Usage in Your Portfolio? • Who tracks usage? • What kind of information do you have at your fingertips? • Who reviews the information? • Is is easy to access and understand?

6. What Is Benchmarking? • A similar comparison would be a miles per gallon rating for a car. • Benchmarking a building documents the buildings energy usage per square foot. • Energy use is standardized by converting electric, gas, oil and/or propane into BTUs (British thermal unit). • Our ideal measurement is BTU/ft2/HDD

7. How to Calculate BTU/ft²/HDD • Calculating the square footage of “conditioned” space allows you to standardize the energy usage per square foot of conditioned space. • After we have our BTU/square foot (ft2), it’s then standardized again for climate conditions so buildings in every climate can be compared. This is done by dividing by Heating Degree Days (HDD) which can be found at www.weather.com. Example: 10,000 ft2 Gas Heated Building in Chicago 10,634 therms/yr x 99,976 = 1063144784 BTU 9,845 kWh/yr x 3412 = 33591140 BTU 1096735924 BTU/yr ÷ 10,000 ft2 = 109674 BTU/ft2 109674 BTU/ft2 ÷ 6536 HDD = 17 BTU/ft2/HDD

8. Heating Degree Days (HDD) Heating Degree Days are a measure of how much (in degrees), and for how long (in days), outside air temperature was lower than a specific base temperature

9. Cooling Degree Days (CDD) Cooling Degree Days are a measure of how much (in degrees), and for how long (in days), outside air temperature was higher than a specific base temperature

10. Calculating HDDs & CDDs Daily TempDefined AsDescription CDD (T - 65) T is daily Average Temp (F). Daily CDD less than 65F, CDD = 0 HDD (65 - T) T is daily Average Temp (F). Daily HDD greater than 65F, HDD = 0. Average Tmax + Tmax (High) & Tmin (Low) (Mean) Tmin 2 whole values. Temp of the day

11. What Affects Energy Use? • Weather conditions (if you are looking at heating or cooling bills) • Changes in building occupancy • Occupants’ behavior • Ex: Failure to close doors and windows • Ex: Using air conditioners in the winter due to over heating • Equipment failure • Building improvements

12. Energy Benchmark Targets CategoryTarget for High Performance Space <10 BTU/ ft2/HDD Cooling <10 ft2/CDD Consider an Energy Audit >15 BTU/ ft2/HDD >15 BTU/ ft2/CDD Consider Low Hanging Fruit Upgrades 11-14 BTU/ ft2/HDD 11-14 BTU/ ft2/CDD HDD= Heating Degree Day CDD= Cooling Degree Day ft2 = square feet

13. High Performance Energy Benchmark Examples • 1st Energy Star Certified Multifamily Building in NYC operates at 6 BTU/ft2/HDD • This building was built and designed to be energy efficient • 100 Unit Multifamily Building Retrofit in NJ operates at 8 BTU/ft2/HDD • As a retrofit project, this building was not designed to be energy efficient.

14. Sample Energy Use Report

15. Sample Energy Use Report Source: Bright Power

16. Electric Use (kWh/ft2/Month) One High Use Bldg Which buildings should we target for electric reduction? 0.015 0.010 0.005 Dec 2006 Sep 2007 Mar 2006

17. Energy Use In BTU/ft2/HDD

18. Which Buildings Should Be A Target For Action? Energy Use in BTU/ft2/HDD

19. Energy Use & Costs In A Multifamily Building Energy usage per end-use Energy costs per end-use

20. Sample Energy Usage Report

21. Sample Report From Portfolio Manager

22. Ashes To Green: Cambridge MA Energy Retrofit • Building Envelope • Walls Polyicynene R-19 in walls • Roof – R40 • Low E Glass windows • HERS 34 • PV & Solar Domestic Hot Water

23. Retrofit (Blue Line) Achieves Reductions

24. Data To Organize • Years worth of bills • Know your meters and what they serve • Square footage of conditioned space • Special conditions or events in past year – what would make the data odd? • Difficult to determine exact square footage • Rentable ft2 vs. gross ft2 • Heating Degree Days www.weather.com

25. Sample Software Options • Bright Power www.brightpower.biz • Building Performance Compass www.psdconsulting.com/buildingperformance • EPA Portfolio Manager www.energystar.gov/index.cfm?c=evaluate_performance.bus_portfoliomanager • WegoWise www.wegowise.com • Energy Scorecards www.energyscorecards.com • Your own spreadsheet

26. Review Learning Objectives • Identify 2 reasons to track energy use • Identify heating and cooling “benchmark” energy targets • Identify key information needed to track energy use Turn to Benchmarking Exercise 1: Benchmarking Energy Usage