This morning, the Roadster was taken out for one of its last road trips for a while – the Urban Cycle course around Adelaide, heading up into the hills through Belair and then down through Magill and North East Road before returning to the city centre to attend an official welcome by the SA premier, Mike Rann.

After 3,147 kilometres, we’ve successfully driven our team all the way from Darwin to Adelaide, with the Roadster travelling completely on electric power – and we set a world record on the way. Nothing to laugh at!

Now, for those of you a little confused about the nature of this Eco Challenge, and whether or not it was a race, and if you’re wondering how well each of the cars did, I’ve got a few numbers for you. Unfortunately, these numbers do not relate to the two electric cars (the Roadster and the Deep Green Research Honda Civic) – those are coming tomorrow once the data-monkeys can crunch some numbers.

So. For the rest of the pack, their ‘performance’ is based upon a comparison with published Australian Design Regulation figures. This is how it panned out, for each of the VFACTS classes entered in the Challenge:

As you can see, everybody’s a winner! (Well, almost…)
See you tomorrow night at the presentations, we’ve been told there’s a few more awards that they haven’t announced just yet!

Congratulations to everybody involved – it wouldn’t have been the same without you!

Gliding Sky

A brilliant day for the last long distance run of this event.

Mild tailwind, a smooth road, and a sky full of cumulus clouds that a glider pilot loves to see (well, almost as much as he likes to see it from the air :) ).

Previous, far longer, stages made this 300 km journey seem very short indeed.

Pit Stop

The good weather and great road meant that we had energy to spare, and we drove this stage mostly at 90 km/h, relatively fast for an ‘economy’ event. We even had time for a quick pitstop along the way.

It took some adjustment to finding ourselves back in a large city like Adelaide, after a week in the bush. Even the presence of traffic lights seemed like a bit of a culture shock.

We ended the stage today at the Torrens Parade Ground in the city, which is the holding point for both competitors vehicles and support vehicles for the event until it is fully completed on the weekend.

Torrens Parade Ground

Tomorrow (Friday) sees us complete one last event stage, the ‘Adelaide Urban Cycle’, testing the fleet in city conditions.

Its ‘only’ about 100 km, so I expect to have a great time driving around the streets of my home town – for the first time ever in this car (and alas, given that its event road permit expires on Saturday at midnight, also for the last time in a while… sniff :( ).

I’ve got lots of other things to write about regarding the event, which I hope to do next week once we’ve all packed up from this very intense week.

Meantime, for anyone in Adelaide who’d like to see the Eco Class cars:

We will complete the Friday stage and then drive in a convoy with police escort up King William St to a display area in Victoria Square, arriving at a ceremonial finish point there at about 2pm.

The cars will also be on display at Victoria Square on Saturday (31st October 2009) from 9am until 4pm, and that display will mark the official end of the event.

I’m already keen to do this again next time. Its a stunning life experience.

Emilis is an old friend with whom I have shared many journeys – most often in sailplanes.

Here are some of his notes from this shared journey at ground level.

Emilis Prelgauskas at a recharging stop

About Emilis Prelgauskas

A 59 year old environmental architect based at Monarto in South Australia, where he has a 100 acre land revegetation site on which he built 25 years ago his self sufficient solar powered home office; who for near to 10 years has driven hybrids, and for 4 decades has flown sailplanes.

The common theme here is an abiding interest in effective resource use,  in particular energy efficiency.

The sailplane mindset is to gain energy and use it appropriately in speed and direction to maximise flight.

His 2000 Prius has 230,000km with minimal repair cost and a lifetime 4.7 l/100km fuel use. His partner Rachel has a 2005 model, and is achieving 4.3 average with the same drive style.

Driving Technique

The Tesla Roadster distance record drive of 27th October 2009 drew on these approaches to look to extract mileage during the drive.

Traditional wisdoms from fossil fuel cars are to hold steady direction and high gear and torque band optima.

Hypermile thinking more closely follows the sailplane mode of minimising energy loss and maximising effective work:

• speed is varied in line with (even minor) road elevation variation, looking to crest each peak with minimum ascent energy use, and maximise speed on downslopes at less than the speed at which aerodynamic losses rise.
• entering regen mode in the electric drive system is minimised
• position on the road is adjusted to seek the least rolling resistance

On the Alice Springs – Coober Pedy drive, sections paved with a smooth ‘hot mix’ surface offered almost 1kW less resistance than gravel topped bitumen segments. Alternate sections and road widening sections of different surface types were found along the stage.

Heavy trucks have dimpled the most used road travel line through the bitumen into the sub-grade. Less resistance was found on the unused road shoulder and its thick line marking paint.

Pot holes and imperfections were studiously avoided.

A varied line on the road width was therefore sought.

With the factory standard Tesla, none of the usual vehicle tweaks (thin high pressure LRR tyres, aero mods, etc.) were available on this trip.

Instead cruise control was used as a hand throttle to promote precise and gentle change speed control.

The result was high driver workload even at the modest speeds being used.

But with record distance results.