Mike Triassi
New Member
Honda rates the Clarity at 110 MPGe in electric mode....finally got close after 7 months!
Most information you find about plug in hybrids is on electric range. During our upstate NY winter there were many days that the range was close to 30 miles but now that it is warmer it is getting the rated range of about 47 miles. Range is good information but I am more interested in efficiency and cost to operate so I have been tracking odometer, gas usage, and electricity usage closely and have now superimposed weather info. Below is a graph of how it did.
Scales on MPGe, Farenheit temps, and percentages are aligned for easier reading.
October 2018 is before a smart charger was installed so it is just a guess.
MPGe calculation
Some notes on how these calculations were done. A home JuiceNet charger and the ChargePoint network provide detailed charging records of electricity usage. Gas usage is based on logs of gas fill ups. Since February 2019, I am filling up at the end of the month whether it is needed or not. I had to interpolate monthly usage prior to that. This should be fairly accurate though since they were all within a few days of the month end and I only use 2 to 4 gallons per month. MPGe calculation is based on a conversion of 33.6 KWHr per gal of gas in summer (June-Sept) and 33 KWHr per gal in winter. The MPGe combined number should be very accurate.
Hybrid and % Electric Distance estimates
Determining Electric MPGe and % Electric Distance is estimated by deducting the estimated gas miles using Honda's rating of 42 MPG and a winter de-rating of 32 MPG in winter assuming that the starting and stopping in cold weather will be detrimental to performance. I wish Honda would provide a computer odometer reading of Hybrid vs Electric miles. Even using less aggressive de-rating of 36 MPG does not change the graphs all that much.
Observations
It was surprising that the winter performance took such a big hit. Tracking an SUV performance for four years it would go from 25 MPG in summer to 21 MPG in winter (16% drop). It is not obvious how much temperature impacts performance versus snowfall on the ground. Next winter maybe there will be some all electric months to get a better sample. There was only one month so far that was all electric and it was in April 2019.
As far as cost of operation, costs for a hybrid vehicle in these colder 7 months of operation would have been about $499 at 36 mpg (mostly winter) assuming $2.80 per gallon for regular gas. It actually cost approximately $317 using ethanol free gas at about $3.00 per gallon and electricity at $0.10 per KWHr (and some free electricity on ChargePoint network).
Things should get much better in the summer. In May, 984 miles traveled in a hybrid vehicle getting 42 MPG would have cost $65.60 assuming $2.80 for regular gas. It cost $36.25 for 3.97 gallons at $3.35 for ethanol free gas and 229.54 KWHr at $0.10 plus 20.79 free KWHhr on ChargePoint.
On a final note. I really like the car. It is fun to drive and has a roomy truck. It was a great price after $7500 federal and $1800 state rebates. The techy side of me just wants to better understand how it performs. It would be great to hear what everyone thinks about this approach to estimate MPGe numbers and cost of operation. All ears for better ideas.
If anyone knows a way to get electric miles on Clarity using OBD port or any way else it would be much appreciated.
Notes
1) Snow tires were used from Nov 2018 to Apr 2019
2) Most of my miles were city but I do not have a good breakdown of highway vs city.
3) I drove 6420 miles in 8 months (802.5 miles per month) using 2398 KWHr of electricity and 27.79 gallons of gas. 56.27 KWHr were free on the ChargePoint network.
4) Weather data and number of days with snow on ground came from this site...
https://www.usclimatedata.com/climate/rochester/new-york/united-states/usny1232
Most information you find about plug in hybrids is on electric range. During our upstate NY winter there were many days that the range was close to 30 miles but now that it is warmer it is getting the rated range of about 47 miles. Range is good information but I am more interested in efficiency and cost to operate so I have been tracking odometer, gas usage, and electricity usage closely and have now superimposed weather info. Below is a graph of how it did.
Scales on MPGe, Farenheit temps, and percentages are aligned for easier reading.
October 2018 is before a smart charger was installed so it is just a guess.
MPGe calculation
Some notes on how these calculations were done. A home JuiceNet charger and the ChargePoint network provide detailed charging records of electricity usage. Gas usage is based on logs of gas fill ups. Since February 2019, I am filling up at the end of the month whether it is needed or not. I had to interpolate monthly usage prior to that. This should be fairly accurate though since they were all within a few days of the month end and I only use 2 to 4 gallons per month. MPGe calculation is based on a conversion of 33.6 KWHr per gal of gas in summer (June-Sept) and 33 KWHr per gal in winter. The MPGe combined number should be very accurate.
Hybrid and % Electric Distance estimates
Determining Electric MPGe and % Electric Distance is estimated by deducting the estimated gas miles using Honda's rating of 42 MPG and a winter de-rating of 32 MPG in winter assuming that the starting and stopping in cold weather will be detrimental to performance. I wish Honda would provide a computer odometer reading of Hybrid vs Electric miles. Even using less aggressive de-rating of 36 MPG does not change the graphs all that much.
Observations
It was surprising that the winter performance took such a big hit. Tracking an SUV performance for four years it would go from 25 MPG in summer to 21 MPG in winter (16% drop). It is not obvious how much temperature impacts performance versus snowfall on the ground. Next winter maybe there will be some all electric months to get a better sample. There was only one month so far that was all electric and it was in April 2019.
As far as cost of operation, costs for a hybrid vehicle in these colder 7 months of operation would have been about $499 at 36 mpg (mostly winter) assuming $2.80 per gallon for regular gas. It actually cost approximately $317 using ethanol free gas at about $3.00 per gallon and electricity at $0.10 per KWHr (and some free electricity on ChargePoint network).
Things should get much better in the summer. In May, 984 miles traveled in a hybrid vehicle getting 42 MPG would have cost $65.60 assuming $2.80 for regular gas. It cost $36.25 for 3.97 gallons at $3.35 for ethanol free gas and 229.54 KWHr at $0.10 plus 20.79 free KWHhr on ChargePoint.
On a final note. I really like the car. It is fun to drive and has a roomy truck. It was a great price after $7500 federal and $1800 state rebates. The techy side of me just wants to better understand how it performs. It would be great to hear what everyone thinks about this approach to estimate MPGe numbers and cost of operation. All ears for better ideas.
If anyone knows a way to get electric miles on Clarity using OBD port or any way else it would be much appreciated.
Notes
1) Snow tires were used from Nov 2018 to Apr 2019
2) Most of my miles were city but I do not have a good breakdown of highway vs city.
3) I drove 6420 miles in 8 months (802.5 miles per month) using 2398 KWHr of electricity and 27.79 gallons of gas. 56.27 KWHr were free on the ChargePoint network.
4) Weather data and number of days with snow on ground came from this site...
https://www.usclimatedata.com/climate/rochester/new-york/united-states/usny1232
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.. The mileage cost of turning on the 2 baseboard heaters is extreme! AC has almost no effect -getting 98 km (59 miles) with AC on. As far as comparing mileage with the ICE - that is actually not fair - as the waste heat from the engine provides cabin heat. JMHO YMMV
