This is how Tesla was able to increase range for some Florida owners fleeing Hurricane Irma

Late last week, as Irma was bearing down on Florida as a Category 5 hurricane, and many inhabitants of the state were evacuating, a lone Tesla owner contacted the carmaker and asked for an increase in range to be able to escape the storm more easily.

That owner, according to Tesla, did not have the current base Model S or X with a 75 kWh battery pack. For a period of time, Tesla sold the Models S and X with a 75 kWh pack that was limited by software to 60 or 70 kWh. For $6,500, owners could upgrade to the full 75 kWh capacity.

Most owners were upgrading, so Tesla discontinued the cheaper option. However, some of those vehicles are obviously still on the road, and Tesla certainly did the right thing by maxing out their range in Florida. (The upgrade will remain in effect until September 16, and it really was as simple as flipping a switch - or beaming out some computer code.)

So what's going on with paying about $60,000 for a Tesla that's actually toting around a battery than can serve up the same range as a car that costs much more?

For Tesla, the idea was twofold. First, have a cheaper car to sell while waiting for the less-expensive Model 3 to arrive. Second, create an upselling opportunity.

There were other factors, chiefly Tesla not being forced to produce lots of different battery packs. Sticking with just the 75 kWh pack and restricting its charging capacity means only a single "base" battery had to be manufactured.

Owners also got some time to determine if they wanted the additional range. Tesla is now doing something similar with its Autopilot technology: all new vehicles have the hardware, but Tesla "unlocks" capabilities using software, if owners want to pay the additional cost.

This might all sound a bit weird if you're used to gas-engined cars that have a stated range and that's it. But for Tesla, managing variations using software makes sense, given that the company sells only three vehicles currently.

The cheaper versions of its cars aren't for sale anymore, but putting them on sale in the first place was Tesla solution to competing in effectively only two segments, and luxury ones at that: mid-size sedans and SUVs.

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