Why are you so keen on electric cars?

It’s something I’ve been obsessed with since I studied physics at college — electric cars, space exploration and the transition towards a sustainable economy.

What has the reception for the Model S been like?

Very strong. We already have about 2000 deposits of $5000 for a car that won’t even be in production for a couple of years. We haven’t been promoting it, but so many people have asked to join a list that we’ve had to agree.

It looks nearly complete. Is it?

People like the look of it, but we still have plenty of development to do. And I’m not really happy with the interior package. We’re going to find at least 3cm more head room and some more room in the boot, too.

It’s said we need a battery breakthrough for electric cars to make a bigger impact. Is it coming?

Yes. In fact, we are making progress all the time. Over the past few years the energy density of the lithium ion battery has been expanding at a rate of 10 per cent a year. That’s big progress.

How can a car like the Model S be made suitable for long journeys?

Two ways. It can be quick-charged using high-voltage equipment: the battery pack can go from 10 per cent capacity to 90 per cent in 45 minutes, while you’re having lunch. Or there can be a quick-change system for the battery. We see those being set up on intercity highways. There’ll be no need for them in urban areas. The standard Model S will have a 230 to 250-mile range.

Could Tesla ever get interested in building hybrids?

No, our focus is on pure electric cars. I believe hybrids really only provide a transitory phase from gas-fuelled cars to electrics.

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