I can't really drive as long as I used to do. Not anymore. I would probably be fine taking a stop every four hours or so, for fifteen to thirty minutes, from now on. I'm just not equipped to do the sort of banzai runs I did a couple of decades ago.
That said, the first car I ever bought had the most range of any vehicle I have driven since. Rated at 28 MPG, I actually got something closer to 33 MPG. And that was with my setting the cruise control at 85 MPH while driving across I-10 and I-20. I could drive 530 miles in about six hours, then stop to fill up -- I wouldn't even start looking for a gas station until I had gone 450 miles. And the tank would typically still have another gallon or more inside it.
I would like to have an electric car that was capable of being driven the same way -- even though I can't personally drive that way anymore. That's because I have a sneaking suspicion that driving electric would excite that part of my youthful nature that loves to do banzai runs again. I believe the very experience would be enough to shake me from the doldrums and make driving a happier experience.
I've driven the same route from Los Angeles to the Family Homestead in Mississippi in cars that barely had a 250-400 mile highway range before. It was agonizing to have only half the range I was used to in my first car. Some of them had short range because they were
'economy' cars with tiny fuel tanks. Others were big, huge SUVs that ate gas like no tomorrow. Either way, I had to stop more often than I felt was necessary to make the trip.
It was nice knowing I could use 90% of the fuel without any range anxiety at all. I get the impression that many suffer from range awareness in an electric car when they have only used 70% of a charge. If you are a person that chooses not to charge beyond 90%, and you begin to panic once the battery is down to 20% capacity, the difference is that 70%. So the trick is to make sure that your own personal needs for daily, weekly, or road trip driving are handled by 70% of the battery pack capacity.
So effectively, when there is talk of a
'500 mile battery pack', what people really mean is that they must have a 350 range while using only 70% capacity. The EPA rates the Tesla Model S as using 380 Wh per mile. So by their numbers, a 500 mile battery pack would have to be 190 kWh in total capacity. 70% of that would be 133 kWh for 350 miles.
For a Tesla Model S to have range like my old car from 25 years ago, it would need a total range of about ~642 miles, to allow a cruising range of 450 miles, while leaving a 20% buffer of ~128 miles to find a Supercharger. That would require a ~244 kWh battery pack.
The tricky part, of course, is that the EPA doesn't actually use the energy stored in the battery pack for their calculations. They use the amount of electricity that leaves the wall, on its way to charging the battery pack. So any losses due to heat, or induction, are added to the efficiency totals, skewing them somewhat. In reality, people who own the Tesla Model S tend to average 280 Wh to 320 Wh per mile in their regular driving. That makes for a big difference, even if you split the difference, and call it 300 Wh per mile.
So really, it should only take a 192 kWh battery pack to achieve a 642 mile range... And only a 150 kWh battery pack to have a 500 mile range. But how much to pay for them? There is a lot of talk about what Tesla Motors' cost is in dollars per kWh for batteries. Well, let's presume that Tesla would charge a Customer three times their own cost to upgrade, shall be? That means that if Tesla's cost is $250 per kWh, they would charge their Customers $750 per kWh. So...
ESTIMATED TESLA MOTORS COST/
RETAIL BATTERY REPLACEMENT
(USD PER kWh)
kWh
| 75/225
| 100/300
| 150/450
| 200/600
| 250/450
|
60
| 13,500
| 18,000
| 27,000
| 36,000
| 45,000
|
85
| 19,125 | 25,500 | 38,250 | 51,000 | 63,750 |
100
| 22,500 | 30,000 | 45,000 | 60,000 | 75,000 |
135
| 30,375 | 40,500 | 60,750 | 81,000 | 101,250 |
150
| 33,750 | 45,000 | 67,500 | 90,000 | 112,500 |
170
| 38,250 | 51,000 | 76,500 | 102,000 | 127,500 |
220
| 49,500 | 66,000 | 99,000 | 132,000 | 165,000 |
Since at least one Customer has reported a cost of ~$45,000 to replace an 85 kWh battery pack, and someone else has paid roughly ~$32,000 to replace a 60 kWh battery pack, I think it is safe to assume that Tesla Motors' current cost is likely below $200 per kWh. Thus, with a 30% reduction in their cost with the advent of the Gigafactory, they will likely be under $140 per kWh from that point forward. So retail cost for capacity would be somewhere in the $300-to-$420 range.
The real question is:
How much range do you want to add? 15 kWh equates to 50 miles of range, and would have a retail cost of $4500-$6300. 25 kWh adds 83 miles at a $7,500-$10,500 higher cost. 35 kWh gives 116 miles more, for a $10,500-$14,700 premium. 50 kWh allows 166 miles of total go power, and would cost between $15,000 and $21,000 as a bank statement hit.
I still don't think a sub-60 kWh battery pack should be offered for the Tesla Model ☰ at all. But I believe these relative costs may point to what you may expect as price differences at different trim levels based upon battery capacity. That is why I have hypothesized battery pack capacities as 60 kWh, 85 kWh, and 135 kWh. A 25 kWh increase from 60 kWh, and a 50 kWh increase from 85 kWh to 135 kWh.
So if a Model ☰ 60 were to cost $34,900... A Model ☰ 85 may be priced between $42,400 and $45,400... And a Model ☰ 135 may cost in the range of $57,400 to $63,400. I rather expect the base prices will be on the low end of that scale, and that options packages and accessories will add more to Tesla's bottom line.