- Q. A customer asked me how to compare the cost of
different heating fuels (natural gas, propane, oil, and
electricity). Can you provide a chart with this
information?
A.Energy and sustainable design consultant Andy
Shapiro responds: The tables at right are based on seasonal
delivered efficiency. Because it accounts for equipment, pipe,
duct, and other losses, seasonal heating efficiency is lower
(by about 5% to 15%) than the listed efficiency of the
equipment (the AFUE, or annual fuel utilization efficiency) or
the steady-state tested efficiency.
| Oil |
| Cost per million Btus,
delivered |
| Cost per
gallon | 50%
efficiency | 70%
efficiency | 85%
efficiency |
|
$0.80
|
$11.76
|
$8.40
|
$6.92
|
|
$1.00
|
$14.71
|
$10.50
|
$8.65
|
|
$1.25
|
$18.38
|
$13.13
|
$10.81
|
|
$1.50
|
$22.06
|
$15.76
|
$12.98
|
Efficiencies for oil equipment range
from 50% for lower-efficiency water heaters to 85% for the best
oil furnaces and boilers. Older boilers typically have seasonal
efficiencies around 70%.
| Propane |
| Cost per million Btus,
delivered |
| Cost per
gallon | 50%
efficiency | 75%
efficiency
| 90%
efficiency |
|
$1.00
|
$21.39
|
$14.26
|
$11.88
|
|
$1.25
|
$26.74
|
$17.83
|
$14.85
|
|
$1.50
|
32.09
|
$21.39
|
$17.83
|
|
$2.00
|
$42.78
|
$28.52
|
$23.77
|
|
$3.00
|
$64.18
|
$42.78
|
$35.66
|
| >Natural gas |
| Cost per million Btus,
delivered |
| Cost per
ccf or therm | 50%
efficiency | 75%
efficiency | 90%
efficiency |
|
$0.70
|
$14.00
|
$9.33
|
$7.78
|
|
$0.85
|
$17.00
|
$11.33
|
$9.44
|
|
$1.00
|
$20.00
|
$13.33
|
$11.11
|
Efficiencies for propane and natural
gas equipment range from 50% for lower-efficiency water
heaters, to 80-85% for typical new furnaces and boilers, and
90% for condensing furnaces and boilers.
| Electricity |
| Cost per mllion Btus,
delivered |
| Cost/kWh | 90%
efficiency | 100%
efficiency | 200%
efficiency | 300%
efficiency |
|
$0.05
|
$16.28
|
$14.65
|
$7.32
|
$4.88
|
|
$0.08
|
$26.04
|
$23.44
|
$11.72
|
$7.81
|
|
$0.11
|
$35.81
|
$32.23
|
$16.11
|
$10.74
|
|
$0.15
|
$48.83
|
$43.95
|
$21.97
|
$14.65
|
Efficiencies for electric equipment
range from 90% for older water heaters and 95% for new water
heaters to 100% for resistance heating, 200% for typical heat
pumps, and 300% for the highest-efficiency ground-source heat
pumps, depending on particular equipment and
climate.