1. Energy Auditing 101
Morgan King
Campus Lead: HSU, Chico, UCSC
Morgan@seiinc.org
2. 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?
3. 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.
4. Energy Water Environ
What is an energy -
mental
audit? Protect
ion
Health
Cost &
•Systems Approach Waste Fuels
Savings Comfor
t
•Inter-relationships
Outputs
•Comprehensive or Inputs
specific 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/
5. Power vs. Energy
Power – Rate of applied Refrigerator Example
work or energy Energy
• Units: Watt, BTU/hr 1000
900
800
700
Energy – Applied power X
Watts
600
500
time 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
6. 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?
7. Questions
A 100 watt light bulb has a lifetime of 1,000 hours. How much energy
will it consume in its lifetime?
(100 W) X (1,000 hr) X (1kW/1,000 W) = 100 kWh
A 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
9. Questions
How much money will it cost to operate the 100 watt light bulb
over 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
10. Residential Building Energy Consumption
Core Areas of Concern:
HVAC/ Building Envelope
Water Heating
Commercial
Plug Loads
Lighting
Source: EIA, Commercial Buildings Energy Consumption Survey, Table E-5A, 2008
11. 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
12. Building Shell and its implications
on 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
structure
For maximum efficiency and comfort, the
thermal boundary and air barrier must be
continuous and in contact with each other!
13. Examples of where the thermal boundary and
air barrier are not intact
14. Building Envelope - Insulation
Insulation – slows heat transmission, reduces
temperature fluctuations, reduces size of heating For Cal:
and cooling systems, and reduces wintertime Attic: R30 – 50
condensation by raising surface temperatures and Wall: R13-15
preventing cool interior temperatures. Floor: R19-25
R-Value – resistance to heat loss. Higher the R the
better.
R Values are additive!
Example: What is the R-Value of the following wall
system?
Insulation: R-Value = 12 (approx 4 inches)
Exterior Siding: R-Value = 3
Interior Siding: R-Value = 3
15. Conductance
U-Factor – measure of thermal
conductance of a building U = BTU/ft2 x ºF x hour
material. Small U means poor
conductor. 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
16. 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/h
Image Credit: Preservation Premium Windows and Siding
http://www.preservationcollection.net/i/Windows/
17. 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!
18. 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
21. Plug Load Exercise
Energy Consumption Energy Costs CO2 Emissions
Phantom
Phantom Phantom Phantom Phantom Run Load Total
Plug 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.
22. Lighting
There 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
25. Lighting
Illuminating
Engineering Society
(IES)
Guidelines for
Illuminance Levels
26. Lighting Exercise
Conduct 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: $0.13/kWh and 1 lbs CO2/kWh
27. Economics of Energy Efficiency
• The more energy a home uses, the greater the potential for savings!
• Cost variables include purchase price (capital cost), installation, life-
span of retrofit, savings, and payback period
• Simple Payback (SP), Life-Cycle Savings (SLC), Savings to Investment
Ratio (SIR) preferred SIR is greater than 1.1
SP = Initial Cost($) / Annual Savings($/yr)
SLC = Annual Savings($/yr) X Life expectancy (yr)
SIR = Life-Cycle Savings ($)/Initial Cost ($)
28. Cost Effectiveness of Retrofits
Homeowner 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
