Solar cars in the WSC each form part of a convoy – a typical convoy is shown above (click to zoom). The lead (front) escort vehicle and chase (rear) escort vehicle ride immediately in front of and immediately behind the solar car. The chase vehicle carries a warning sign (“CAUTION: SOLAR VEHICLE AHEAD”) that informs other traffic about the presence of the solar car. In addition, the chase vehicle carries emergency equipment like fire extinguishers and a first-aid kit.
Michigan’s lead and chase vehicles for the 2010 American Solar Challenge
The truck (or car with a trailer) rides further behind. It carries equipment and provides the ability to transport the solar car in the event of a breakdown.
Michigan’s semi-trailer driving down the Stuart Highway in the 2011 WSC (photo: Marcin Szczepanski)
The (optional) scout vehicle rides well ahead, checking out road conditions and potential hazards. There may also be additional vehicles, like a media car. All vehicles in the convoy stay in touch with each other using CB radio.
See also this excellent post by Solar Team Twente about their 11-vehicle convoy, illustrated in the infographic below (click to zoom). As is often the case, their chase (rear) escort vehicle also houses the team’s Decision-Making Unit (DMU), who plan the strategy for the race.
Solar Team Twente’s convoy structure (driving left to right)
Scientific Gems 
Food for thought: 10 polluting cars in a convoy for 1 solar car trying to make a point to save the planet . . .
Well, they’re not just “making a point.” This is engineering research and engineering education in action.
It’s the ideas and the training that come out of the race which will hopefully one day help save the planet.
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