That's cool. Dealerships are horrible. Will be interesting to see if they extend that to the new model in 2019. I guess they will if you buy the same package you did.
Saying savings at the pump seems misleading. That's like saying taking Uber everywhere reduces your gas consumption. Nobody says their golf cart is free energy cost. Cost is being transferred to the electricity bill. Could be close to the same $/mile? What is the kWh/charge and miles per charge and we can calculate that $/mile consumption.
The cost for eV on a per mile basis beats gas unless you factor in increased initial cost and that your "gas tank" will be much smaller in 10 years no matter how many miles you put on it.
^^ Thanks for the qualitative answer. I'd like to calculate the quantitative numbers though. Do you know the miles per charge and kWh per charge?
Depends on where you live and your electricity rate. It is 12 cents/kwh where I live. Should be around 8-9 cents/kwh in Houston. Model S is 240-290 miles per charge depending on which battery you have(70kwh or 90kwh pack). Takes 4-8 hours for a full charge at home depending on output. At Superchargers (proprietary Tesla charger) it takes 40 mins for 80% charge. Free. https://www.teslamotors.com/supercharger They are building these everyday.
You need to factor in charge loss (at the cells) and charger loss (at the battery charger) also. It isn't a 100% efficient process from your plug to the kwh put into the pack. Would probably be harder to factor in self discharge as the time spent charged is variable.
Assuming one is paying .12kwh (are taxes included?) and assuming one is averaging 30mpg, electric would be half the cost of petrol? This is the assumption one is paying $2.50 a gallon. The key is to charge up when its not on your dime.
At $2.5 a gallon, and 30mpg, you are paying $2.5/30mpg = $0.083/mile At $0.12/kwh, 70kwh full charge, going 240miles = $0.035/mile Also, depending on your state electricity rates fluctuate during peak/off-peak times. So charging at night should be cheaper.
Your calculations assume a 100% efficiency in converting AC to DC, regulating the voltage/current, cooling, powering the circuit and charging the cells. I mean sorry for "hating on Tesla" but your calculation is garbage.
Yes, it is miles per (kwh at the meter)...not what is reported in the car. There can be as much as 80% efficiency loss between what the electric meter reads vs what the car registers on the dash. Tesla wants to report 91% efficiency, but better data shows less. Research has shown that there is about 82% efficiency between what the meter reads as used vs what the car gets. Thus a 85 kW battery costs you 103.6 kW to charge. Price assumptions: 300 miles/charge for a Model S 85 kW battery (there's a lot of data showing 300 miles is a good measure) 103.6 kWh electricity used to charge the pack at 82% charging efficiency 30 mpg ICE $2.00/gal Houston current price (for midgrade from GasBuddy.com) 10 cents/kWh per Houston TrueCost average (fees included) (btw: my Colorado bill is 14.5 cents/kWh) Tesla = $10.36 per 300 miles (using 82% efficiency to charge the pack) ICE = $20 per 300 miles 2016 Houston Cost Saving is roughly 50% of costs per mile.
Considering his is right (with his justifications and assumptions) and yours is wrong, yes. I think the efficiency of charging he used and the kWh/mile he used are a bit optimistic, but far better than the ones you used. ie none.
That is about what I am ball parking, a 1:2 or 1:3 ratio. Rates will fluctuate for both electric and petrol. Its a bit silly to calculate fuel cost difference when one price is on the low side (petrol). One should at least consider the lifetime ownership of their vehicle's (3-5 years) fuel/recharge rates based on educated guesses of the future. $1.50-$2.00 wont last for long. By the time the Tesla 3 comes out, I suspect we maybe seeing a 1:4 ratio.
I did 10 cents per kWh. You did 12.5 cents. You're simply just missing the 82% efficiency loss during the charging. Your electric bill will be higher than your calculations show. My calculations using your $2.50 / gal and 12.5 cents / kWh are: Tesla = $12.92 per 300 miles ICE = $25 per 300 miles My calculation is a 48% savings Your calculation is a 58% savings
My calculations are on 12 cents not 12.5, but anyways. If you want to be that exact, then you should also take into account the vast majority of home charging will be overnight, when electricity rates are lowest, not the average. For example on Teslas you can set them to start charging at 12 am - 6am etc. Also it is worthwhile to note, you are comparing a 30mpg ICE car to a 4600 pound performance Model S. It may be better to wait and see what the numbers are for the Model 3 - which will have a lower drag coefficient and much smaller/lighter compared to the Model S.
At the end of the day, I am not concerned about theoretical costs. Leave that voodoo to the liberal drones. EV's are not a solution for everyone. They work better for some than others. I am strongly considering one. Two points concern me the most. The first is the proliferation of charging stations. If EV's really take off, will the government help subsidize the cost for businesses to install them. Regardless of charge efficiency, if I am getting a free charge at Hippie Food Mart, or the mall or at work, that is infinite times more efficient than petrol to me, cost wise. A huge cost of petrol is transportation and refining. You can essentially build a charge station anywhere on the grid at a very reasonable rate. Gas station ... not so much. The second concern I have is battery life and replacement costs.
So you did your own calculation now. It is half the $/mile, not even close - at $2.00 gas, in a 30mpg ICE car. Saying savings at the pump seems pretty fair.
