Energy Auditing 101 Morgan KingCampus Lead: HSU, Chico, UCSC Morgan@seiinc.org
Introduction Who am I? Training Goal: Leave today with the motivation and know-how to conduct energy audits on your campus. What’s on tap for today? Energy Concepts and the Building as a System Energy Audit Practice and tool demo Recommendations Strategic Planning Session What are your expectations?
Energy True or False When my appliance is turned off, it’s off. Every unit of energy that goes into a power plant gets converted into electricity. Buying an efficient air conditioner or furnace will reduce my energy bill.
Energy Water EnvironWhat is an energy - mentalaudit? Protect ion Health Cost &•Systems Approach Waste Fuels Savings Comfor t•Inter-relationships Outputs•Comprehensive or Inputsspecific Energy Useful Work•Variety of diagnostic tools Water By- Materials Product/Was te Image Credit: Florida Public Service Commission, http://www.psc.state.fl.us/consumers/house/
Power vs. EnergyPower – Rate of applied Refrigerator Examplework or energy Energy• Units: Watt, BTU/hr 1000 900 800 700Energy – Applied power X Watts 600 500time 400 300• kW X hr = kWh 200 100• BTU/hr X hr = BTU 0 Time BTU –British Thermal Unit - the amount of energy required to raise 1 pound of water by 1 °F ~ 1 wooden kitchen match Natural Gas – Therm – 100,000 BTU Electricity – kWh ~ 3414 BTU
What is Energy Efficiency?To provide the desired amount of ‘work’ for as little energy input as possible η = Energy In – Losses Energy In How efficient is a 100W incandescent light bulb?
QuestionsA 100 watt light bulb has a lifetime of 1,000 hours. How much energywill it consume in its lifetime? (100 W) X (1,000 hr) X (1kW/1,000 W) = 100 kWhA 85,000 BTU/hr furnace is operated for 12 hours per day, for one full year. How much energy has it used in BTU and in therms?(85,000 BTU/hr) X (12 hr/day) X (365 day/yr) = 372,300,000 BTU/yr(372,300,000 BTU/yr) X (1 therm/100,000 BTU) = 3,723 therm/yr
Energy CostsElectricity$0.12-$0.14 per kWh0.514 lbs CO2 per kWh(PG&E)1.3 lbs CO2 per kWh (US)Natural Gas$1.20 per therm13.4 lbs CO2 per therm
QuestionsHow much money will it cost to operate the 100 watt light bulbover it’s lifetime of 1,000 hours, assuming energy costs $0.125 per kWh? (100 kWh) X ($0.125/kWh) = $12.50 How many pounds of CO2 will be emitted from using 3,723 therms/yr to operate the furnace for a year (assuming 1 therm = 13.4 lbs CO2)? (3,723 therms/yr) X (13.4 lbs CO2/therm) = 49,888 lbs CO2
Residential Building Energy Consumption Core Areas of Concern: HVAC/ Building Envelope Water HeatingCommercial Plug Loads Lighting Source: EIA, Commercial Buildings Energy Consumption Survey, Table E-5A, 2008
Energy Audit Focus Areas Focus Area Assessment Tools EE Measures Inspect heating/cooling Air sealing, insulation improvements, equipment, distribution IR thermometer, thermostat settings, window system, system balance, Heating/Cooling Thermal Leak treatments,reduce internal heat gains thermostats, leaks in Detector (cooling), smaller/more efficient envelope, building envelope equipment upgrades Inspect water heating Lower temperature set-point,Water Heating and equipment (e.g. boilers), Thermometer insulate, pipe wrap, heat trap, low Cooling pipes, fixtures, controls, usage flow fixtures behaviors Inspect plug-in equipment, Energy Star upgrade, remove Plug Loads phantom loads, usage Watt meter redundancy, unplugging, (smart) behaviors power strips, plug miser controls Inspect age/type of lighting, Flicker Checker, Lighting Retrofit, task Lighting, Lighting light intensity, lighting Ballast Checker, lighting Controls, de-lamping controls, usage behavior Light meter
Building Shell and its implicationson heating and cooling Building Envelope – separates outside from inside environment Thermal Boundary – limits heat flow inside and outside of conditioned space Air Barrier – limits air flow between inside and outside of structureFor maximum efficiency and comfort, thethermal boundary and air barrier must becontinuous and in contact with each other!
Examples of where the thermal boundary and air barrier are not intact
Building Envelope - InsulationInsulation – slows heat transmission, reducestemperature fluctuations, reduces size of heating For Cal:and cooling systems, and reduces wintertime Attic: R30 – 50condensation by raising surface temperatures and Wall: R13-15preventing cool interior temperatures. Floor: R19-25R-Value – resistance to heat loss. Higher the R thebetter.R Values are additive!Example: What is the R-Value of the following wallsystem?Insulation: R-Value = 12 (approx 4 inches)Exterior Siding: R-Value = 3Interior Siding: R-Value = 3
ConductanceU-Factor – measure of thermalconductance of a building U = BTU/ft2 x ºF x hourmaterial. Small U means poorconductor. U = 1/R What is the R Value of a double pane window in a vinyl frame? R = 1/U = 1/0.46 = 2.17
Quantifying Conductive Heat Loss • Second Law of Thermodynamics – over time systems move from an ordered state to a disordered state – hot to cold, moist to dry, high pressure to low pressure • Conductive Heat loss rate q (BTU/hr) = U (BTU/ft2 x ºF x hr) x A (ft2) x ΔT (°F) Example: U = 0.46 A = 4’ X 2’ To = 48º Ti = 68º q = 0.46 x 8 x 20 = 73.6 BTU/hImage Credit: Preservation Premium Windows and Sidinghttp://www.preservationcollection.net/i/Windows/
Heating/Cooling Audit Focus Area Assessment Tools EE Measures Inspect heating/cooling Air sealing, insulation equipment, distribution IR improvements, thermostat system, system balance, thermometer, settings, window treatments,Heating/Cooling thermostats, leaks in Thermal Leak reduce internal heat gains envelope, building Detector (cooling), smaller/more efficient envelope upgrades equipment Let’s do a heating/cooling audit of this room!
Water Heating/Cooling • 120º max at the tap farthest from the boiler • Low flow fixtures • Shower heads ≤ 2.0 gpm • Faucet aerator ≤ 2.75 gpm • Refrigerated water fountains Inspect water heating/cooling equipment Lower temperature set-point,Water Heating (e.g. boilers), temp Thermometer insulate, pipe wrap, heat trap, and Cooling settings, pipes, fixtures, low flow fixtures, controls usage behaviors
Plug Loads• Watt meter, Energy Guide, name plate, online search
Plug Load Exercise Energy Consumption Energy Costs CO2 Emissions Phantom Phantom Phantom Phantom Phantom Run Load TotalPlug Load Run Operating Run Load Total Run Load Total Load Load Load Load Load CO2 CO2 Name Watts Hours/yr kWh/yr kWh/yr $/yr $/yr CO2 Watts hrs/yr kWh/yr $/yr lbs/yr lbs/yr lbs/yr A B C D E F G H I J K L M#1:Printer 149#2: 100 Phantom load on this printer is 2.8 watts. Run load is 250 watts. Printer is used 500 hrs a year. 1 pound of CO2 per kWh. $0.13 per kWh. Recommend 200 watt printer with no phantom load.
LightingThere are several factors to consider when comparing lamps: – Watt rating and kWh – Light output, in lumens – 100W incandescent = 1750 lumens – 40W fluorescent = 3150 lumens – How long lamp will last (lifetime) – Color Rendition (CRI) – Color Temperature – Illuminance (foot-candles): 1 footcandle = 1 lumen/square foot
Lighting IlluminatingEngineering Society (IES) Guidelines for Illuminance Levels
Lighting ExerciseConduct a lighting audit of the room!What is total energy lighting consumption?What is total energy cost and pounds of CO2?Any recommendations to reduce energy consumption?Assume: $0.13/kWh and 1 lbs CO2/kWh
Economics of Energy Efficiency• The more energy a home uses, the greater the potential for savings!• Cost variables include purchase price (capital cost), installation, life- span of retrofit, savings, and payback period• Simple Payback (SP), Life-Cycle Savings (SLC), Savings to Investment Ratio (SIR) preferred SIR is greater than 1.1SP = Initial Cost($) / Annual Savings($/yr)SLC = Annual Savings($/yr) X Life expectancy (yr)SIR = Life-Cycle Savings ($)/Initial Cost ($)
Cost Effectiveness of RetrofitsHomeowner spends $2,000 on new dbl-pane windows and receives $12 per month reduction in energy cost, what are the SP and SIR if there is a 20 year life expectancy? SP = $2,000 ÷ $144/yr = 13.9 years SLC = $144/yr x 20yr = $2,880 SIR = $2,880 ÷ $2,000 = 1.44