One Tesla Model S owner has been tracking the electricity his car draws from his home charging station since June, and the results may surprise you a bit. Tesla claims that the Model S will achieve a 91 percent efficiency rate when juicing back up from a home charging station, but are they being honest?
For the most part, yes. Rob M form Teslarati tracked the energy the car was pulling form his Tesla-certified home charging station and found about 82 percent of electricity the system was drawing from the outlet was making it into the car. This equals an 18 percent loss of electricity, when most EVs are said to charge at 88 to 90-percent efficiency.
This slightly greater loss of electricity means charging his Model S costs Rob about $26 more than previously calculated for 2,400 miles worth of driving after charging at 90 percent efficiency. He says it would be interesting for another Model S owner to do the same test, as it may yield a different result. Either way, he still saved $334 by driving his Tesla, as that is what it would have cost to fill up a vehicle with an internal combustion engine over the same month-long period. Is that enough to get you to go electric?