Electricity Cost Per Charge = 26 Cents
Electricity Cost Per Mile = 1.3 Cents
A common question is how much
electricity does it take to charge the
battery. To the right we have a charge
rate graph. You can click on the graph
to see a larger version. The chart shows
how much power is being drawn from the
110VAC outlet during the charge cycle.
Each dot represents 15 minutes of charge
time. Charging occurs in two steps,
these are known as bulk charge and float
charge. The first step takes about 6.5
hours as you can see on the graph. This
is where the majority of the charge
occurs. At this point the charger steps
down the power for the remaining 20% of
the charge cycle.
Average power utilization can be
calculated by adding all of the plot points
together and dividing that number by the number
of plot points. In this case we take 83
and divide it by our 40 plot point for
an average power draw of 2.075 amps.
Watts equal voltage times amperage so we
multiply 110 X 2.075 to get 228.25
watts. Our charge time is 9.5 hours so
we multiply the average power draw of
228.25 times 9.5 to get 2.168 kilowatt
hours.
In California, PG&E’s baseline rate per
kilowatt is $.12 (as of August 2008).
Multiply this rate (.12) times the total
watt hours used (2.168) to charge the
battery and we find that it costs about
26 cents to fully charge an exhausted
battery. A fully charged battery has
range of 20 miles with this model so we
can see that it costs just 1.3 cents per
mile for electricity to operate this
scooter. |
