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At the North American International Auto Show in Detroit Tesla had many stories to tell. We displayed three cars, each representing a facet of the Tesla story. VIN 1000 embodied a significant production milestone. The Road Trip Roadster, filthy from its drive to Detroit, was a testament to the durability and toughness of our technology. The Model S symbolized Tesla’s future – the ruby red car dazzled media, fans, and industry leaders alike.

Bill Arnett is a software engineer who envies Renaissance and Enlightenment thinkers – people who tried to understand a large fraction of all human knowledge. During an attempt to retire and spend more time on hobbies such as photography and astronomy, Bill decided to learn HTML by creating an astronomy site. It became so popular that it generated enough revenue through Google AdSense to pay for his Roadster. Another recent project was an iPhone application that simulates mechanical watches.

Two weeks ago, I highlighted how Tesla moved from waves to bits in our motor and charge controller in the PEM. You might have left with the impression that as of June 2007, when the DMC replaced the analog controller, our work as DMC firmware engineers was complete. Fortunately for us (this is fun, remember!), that was far from true.

Ten years ago when I was driving an EV1, one of the best perks was free parking and charging at LAX. I would pull into one of the EV parking places by Terminal One, plug in, and go on my trip. The charger would turn on right away – typically this would be in the middle of the day – and the battery pack would be fully charged even before my plane had left the ground. When I would return a few days later, typically at night, the battery pack would have partially self-discharged and was cold soaked, having sat for days with the charger connected but off.

When I last posted to this blog in May, the news was a mixed bag. Martin (Founder Martin Eberhard) had just officially revised our range expectations down from 250 miles to greater than 200 miles, but we remained committed to holding the line on 4 second 0-60 mph acceleration and delivering the Tesla Roadster with the performance, handling, looks, and safety of a world-class electric sports car. Now it is September and in the last three weeks we have completed performance and range validation testing of Validation Prototype 1 (VP1 aka “the green car”) in order to verify our Tesla Roadster performance claims. I’m extremely pleased to say that the results are in and our hard work has really paid off!

In a battery-powered electric vehicle, regenerative braking (also called regen) is the conversion of the vehicle’s kinetic energy into chemical energy stored in the battery, where it can be used later to drive the vehicle. It is braking because it also serves to slow the vehicle. It is regenerative because the energy is recaptured in the battery where it can be used again.

Editor's note: Our last blog, Good Vibrations, chronicled some of the safety and durability tests we've been running on the Tesla Roadster. It prompted a number of questions, particularly related to climate control. So we convinced Brian, who is fully booked during regular business hours overseeing the tests, to postpone his holiday shopping a little longer and spend some time after work explaining in more detail how we ensure satisfying climate control in the Tesla Roadster. Here are his thoughts…