Electricity Units Pt. 2
 BTU
= a standard unit of measurement to
denote the amount of heat energy in
fuels.
A
BTU is the amount of heat requirement
to increase 1 pound of water by one
degree Fahrenheit
Electricity Units Pt. 2
 According
to some data, the average
U.S. citizen uses 312.9 million BTU per
person, per year
 Per
capita = per person, individual
Electricity Units Pt. 2
 In
order to compare our data we need to
calculate the per capita kWh use in our
homes per year
 Then
find the class average and convert
to millions of BTU ( MMBtu)
 If
the average person uses 312.9 million
BTU per person, per year, how many kWh
does that person use?
1
MMBtu = 293.2972 kWh
 Spend
some time and go over questions
1-4 on the “Home Energy Audit”
worksheet
 Convert
the annual per capita
energy use in the U.S. (in 2011) to
kWh and choose two more
countries to compare
 You
must convert the data from
MMBtu to kWh
 Is
the class below average or
above average?
Consumption per person per state
 The
Average BTU used per person in Iowa
per year is 472,000,000 in 2009
1
kWh = 3412.1416 BTU
 Lets
look at problem #7
Estimating your Home Energy
Use
Heating:
26,500 Watts
7941 Watts
1440 Watts
900 Watts
600 Watts
750 Watts
Furnace, 2000 sf, cold
Furnace, 1000 sf, warm
Space Heater, High
Space Heater, Medium
Space Heater, Low
Gas Furnace
Estimating your Home Energy
Use
Cooling:
3500 Watts
1440 Watts
900 Watts
325-425 Watts
Central air, 2.5 tons
Window unit, Huge
Window unit, small
Fan only