Eight Months in Our Nissan LEAF, "Winter" Season Electric Costs

[Please click on any post to expand the view to the full size]

We've now spent eight months with our Nissan LEAF as a member of the family, and we're still delighted with it.  We drove fewer miles this month, partly due to a trip out of town in our Prius and partly due to some family health issues that required our presence closer to home, but our LEAF continues to be our primary vehicle for most of our driving.  It fits our family of four adults and a toddler very well, and it gives us a good feeling to know that we're driving on electricity.  We aren't emitting any CO2 or other pollutants into the air, and most of our electricity for driving is supplied by solar energy from the 24 solar panels on our home's roof.


As it always has, our LEAF drives quietly and smoothly, with very good pickup from a stop light due to the instant torque of its electric drive train.  No squeaks or rattles have developed and the car drives just like it did when it was brand new.  All of its components have held up well, and the tire rotation (the sole maintenance required) that we had done at the Nissan dealer last month hasn't affected the LEAF's performance at all.

November marks the second recent month under our utility, SCE's, winter rate schedule.  Two major factors about our household electrical use are different this year compared with last year.  One factor is that we have additional family members living with us temporarily, and the second is that we are charging the LEAF this year.  With both of these additional loads in place we've been using seriously more power than last year, almost 500 kWh more in November.  With temperatures dropping and with daylight hours getting shorter, we used slightly more total power than last month and our solar power system generated about 130 kWh less than last month.  I anticipated that with SCE's winter rates being less favorable to our solar credits and with more power usage, we would see a larger electric "bill" this month (really a charge against our annual net metering tab) that would eat into the $316 credit balance that we had at the end of October.  


Indeed, our "bill" this month is about $92, the largest monthly bill that we've had since our solar power system was installed.  But due to the credits built up in prior months because of our Time of Use rate schedule, we still carry a credit of $224 into the last three months of our net metering year.  Evenly divided, we can still receive bills of about $75 a month for the next three months and end the year with a power bill of zero. That is still possible, but judging by our power usage for the first part of a chilly December, there is a good chance that we'll end the year with a bill of some small amount by the end of February, the last month in our net metering year. Stay tuned for the exciting outcome at the end of February.




The Numbers:
2011 Nissan LEAF SL Placed in Service: March 30, 2011
Month:  November 2011
Total Miles at Month End:  7,171 miles
Miles Driven in Month:  775 miles
Electric Power Used for Charging in Month: 243.96 kWh (measured at wall power source, includes public charging)
Public Charging in Month, Power Use: 5.76 kWh 
Charging at Home in Month, Power Use: 238.2 kWh
Energy Efficiency, Month of November:  3.18 miles/kWh (wall to wheels)

Total Charging Energy Used, Lifetime: 2,261.1 kWh (Includes public charging)

Energy Efficiency, Lifetime:  3.17 miles/kWh (wall to wheels)
Energy Efficiency, Lifetime:  31.5 kWh/100 mi
Most Electric Energy Used for Charging in a Day in November: 20.71 kWh  (5.6 charging hours, including 1.8 kWh public charging)
Most Electric Energy Used at Home for Charging in a Day in November: 19.3 kWh (5.1 charging hours)
Least Electric Energy Used for Charging in a Charging Day: 5.8 kWh  (1.6 charging hours)
Average Electric Energy Used for Charging in a Charging Day:  11.3 kWh  (3.1 charging hours)
Household Power Used for Month:  803.8 kWh (without car charging)
Total Power Used for Month:  1,042 kWh (includes car charging)
Solar PV Power Generated for Month:  511 kWh
Net Power Used or Sent to Grid for Month:  531 kWh net used
Electric Bill, So Cal Edison, Schedule TOU-D-TEV:  $92.33 (A charge in this amount will be added to our net metering total charge for the year.)
Solar Net Metering Year Total Cumulative kWh Used at Month #9:  1,317 kWh (Total of 1,317 kWh net used for the year)
Solar Net Metering Year Total Cumulative Cost at Month #9:  -$224.09 (Total cost is a credit for the net metering year to date due to TOU rates)
Cost for Charging Car in November:  $0.00
Cost per Mile:  $0.00
Cost for Charging Car, Lifetime: $0.00
Cost per Mile, Lifetime: $0.00
(If We Didn't Have Solar Power, Est Cost for Charging Car in November: $30.97)
(If We Didn't Have Solar Power, Est Cost per Mile in November: $0.04) 
Average (Mean) Miles per Driving Day in November:  25.8miles
Average (Median) Miles per Driving Day in November:  24 miles
Longest Day's Driving in November:  69 miles
Shortest Day's Driving in November:  1.1 miles
Number of Times we Took the Prius Instead of the LEAF Due to Low Charge: Never
Unexpected Low Charge and Unable to Reach Destination:  Never