
Doing the math
Firstly, thanks to everyone who posted corrections about the Nissan Leaf charging times, and the availability of our Electric Highway (which is capable of charging Nissan Leaf and others) in as little as 30 mins at many motorway services in the UK :)
Now, Tesla says that they can offer free supercharging to their customers forever, and they can do that because all the cost is in the infrastructure, the actual electricity cost isn't so great and they build the charging cost into the car. When we looked at it the cost was around £2,000 to add free supercharging to your Tesla order, or free if you have the top end car - but safe to presume the £2,000 is built into that.
We can see that the 60kW car does 2.9 miles to the kWh and the 85kWh does 2.6 (these are the most gas guzzling EVs on the planet BTW) - and against that you have £2,000 most of which is spent on infrastructure. If you assume infrastructure is free, that £2,000 would pay for about 44,000 miles of driving in the 85kW car at today's prices (assume 12p a kWh).
That's hardly a lifetimes driving - it's more like a couple of years worth - and that assume zero infrastructure cost, whereas Musk says it's the other way round, negligible energy cost.
Something clearly does not add up. Are Tesla making promises they won't later be able to keep?