Revenge of the Tesla Roadster

The Long, Hot Summer of 2012 – Part 2

What fun can I have with the Tesla Roadster this summer? Oh, I know – how many miles range can I get the Tesla Roadster up to? Gosh this is going to be – Such fun!

The Tesla Roadster has two gauges – The first is an ‘Ideal miles’ gauge which is the range you’ll get if you’re driving at a steady 55 mph on the motorway. This is normally about 187 miles on a standard charge and 240 miles on a full range charge. The range charge squeezes every last electron into the battery pack for those long ‘range’ journeys. The second gauge is an ‘Estimated’ range which reports how many miles to empty while you are driving the way you are driving at the moment. Tesla reckon that if I drive the car how it’s designed to be driven I’ll get 187 miles to empty… I think I can do better than that.

‘A wise man once told me that it is far, far better to cruise than to Regen.’

Let’s see what happens… The first morning of driving the Tesla saw its ‘range’ miles stand at 198, hmm okay, that’s already better than Tesla’s reckoning. On the second morning it’s at 222, on the third morning it’s 238, and while driving it went up to 247 – so I must be driving it correctly (ed: Or not!). The fourth morning it was at 238 again, – hang on, did Michael go out in it that night? – but, then Michael did drive it for a couple of days and it went back down to 160… he must have been driving it rather quickly! When I drove it again after the rather dismal 160, I managed to get it back up to 192 just driving it gently on a 10 mile journey. I’d be interested to see what I can get the range up to over a weeks worth of driving – Michael can have the ActiveE for a whole week… But, does that mean that the ActiveE will come back with a low range?  I expect so… Ugh!

Well the fun didn’t last long – my personal mileage challenge has taken a complete nose dive. I think Michael saw me having too much fun with the Roadster and couldn’t take it anymore! Every time he drives it, the estimated range is always down to 160, so I spend the whole day (35 miles) driving gently and usually manage to get it back up to 200. Maybe I should hide the keys so he can’t take the Tesla Roadster until I’ve at least driven it for the whole week. As each Monday morning rolls around, it’s looking promising that I’ve got the Roadster for the week, but then by Tuesday evening, “I need to go further than the ActiveE’s range tomorrow so I’ll have to take the Roadster”, says Michael… hmm… I think it’s more that he misses his Tesla!

My conclusion – I have been able to get the range of the Tesla Roadster up to 247 miles on a ‘standard’ charge and would probably have maintained that range if I was driving it all the time – that’s a third more than Tesla estimate – could I get an extra 80 out of a ‘range’ charge? Could I get 320 miles on a full charge? In 2009, a couple of Aussies managed to go 313 miles in the blazing heat of the Australian outback – perhaps I should have been driving!

I consider my local attempt to be a success and will continue trying to improve on that when I get the chance to drive it again and, if I have the car for more than a couple of days. I’m going to be doing more miles per day than Michael soon so I’m back to the ActiveE… am I sad about that? Actually, yes I am a little, however, the roads I will be driving on are not that great, there are so many potholes, so I’d rather be in the ActiveE for that.

My other conclusion (and I expect the truth)… I think Michael was just a little bit jealous that I was driving the Tesla Roadster.

Oh and by the way – the ActiveE came back with a very low 3.6 mls/kWh after the swap. I had left it at the beginning of this swap at 4.2 mls/kWh. It has taken almost 4 weeks of my driving (but then Michael ruins things at the weekends) to get it back to 4.1 mls/kWh.

Interesting note – the ActiveE has returned from it’s third service (only a day and a half this time – well done BMW!) with a little problem. It would appear that some software update or something has me able to maintain a rather good 4.5 mls/kWh for over a week now, I’m even seeing 4.6. Here’s the problem – I’m now on a mission with the ActiveE to see how high I can get the mls/kWh up to – sorry everyone who’s driving behind me!!  Now, if only there wasn’t quite so many hills around here…

What affects efficiency?

Well that’s easy… Speed, hills and temperature.

Speed – The faster you drive the less efficient the car is as it works harder and harder against wind resistance.

Hills – We’re talking uphill here… well that just ruins everything as the car has to literally lift itself up! It’s not a lightweight car but, whilst it’s true that it’s weight actually improves the performance of the regenerative braking, overall, it still loses more than it gains.

Temperature – As the outside temperature starts to go down, so does the mileage range even with temperature managed batteries – at lower temperatures, the batteries can’t soak up as much energy, nor can they release it as efficiently. Using the heater in the car reduces the range too – precondition whenever you can.