19% Kwh lost? or 23.5% more Kwh used than claimed by Model S? Seems too much lost.
So many of you on the forum are much more knowledgeable than I am, what am I missing?
Took delivery of Model S in early December. 2nd meter installed prior to delivery. Only one outlet at the other end of the 2nd meter - Nema 14-50. Just received my 2nd electric bill.
Total of 735 Kwh charged by PG&E from early December to Jan 31, 2013.
Model S instrument panel says I used 595 Kwh to Jan 31.
735 is 23.5% more than 595. Or, 19% of 735 is lost as Model S says only 595 Kwh used.
Where is the loss?
- Tesla ownership experience tells me charge efficiency is 92%. Perhaps 92% is ideal, so real life efficiency is less than 92%?
- Model S loses miles just sitting there (4.1 and 4.2 both). Does the control panel register the Kwh lost? I don't think so.
- When one is in the car with screen on, climate on, does control panel register the Kwh used? Not sure.
- Any other source of loss?
Regardless, In 8 weeks, Model S says I went 1694 miles on 595 Kwh, or 351 wh/mile.
PG&E says I used 735 Kwh, or 434 wh/mile. Big difference!! 23.5% more than 351 wh/mile.
My region has among the highest electricity charge in the country. For those in PG&E territory other than Palo Alto or with solar panels, virtually everyone quickly ends at 33.5 cents per Kwh. With the 2nd meter and on E9 time of use rate card, I averaged 11.2 cents per Kwh. The 2nd meter was costly to put in, but I should make it back in a few years.