UK car shapes up for solar challenge

This is the super-sleek shape a British team hopes can bring it glory in next year's World Solar Challenge.

The 3,000km race through the Australian desert, from Darwin to Adelaide, is the classic test for innovators trying to push the boundaries of what is possible with a Sun-powered vehicle.

Solar Team Great Britain will be entering the event's Cruiser Class, which puts the emphasis on practicality as well as efficiency.

The cars must carry passengers.

They cannot simply be some pencil-thin, ultra design that only a driver can squeeze into through a removable cockpit canopy.

"Cruiser Class is about two or more seats. It's about a practical car," said Steven Heape, who leads the team of volunteers behind Solar Team Great Britain.

"In many ways, it's the class that goes back to the roots of the competition. It was envisaged as a design competition for cars that could run on the Sun, but extrapolating that forwards it meant we would ultimately get to the productionisation of solar vehicles."

To succeed, the Brits will have to overcome expert teams from the Netherlands. 

Throughout its 30-year history, the competition has been dominated by the Dutch - so much so that 2017's race is being promoted on Twitter with the hashtag #BWSCTakeOnTheDutch.

Mr Heape, an engineer and renewables consultant, has pulled together a range of talents. 

At one end, he has students; at the other, he has experienced hands from the likes of Airbus and QinetiQ. 

There's even a former Concorde aerodynamicist in the group.

Development work on the car is coming on apace. The motor and drive technology have been identified, and the vehicle control system is already running on a test bench. 

The chassis is expected to go into production in mid-January. By early New Year, the final shape of the car should also have been frozen as well. 

"What you see is our Version 5.1," explained Mr Heape. 

"We have a strategic relationship with the Centre for Modelling & Simulation (CFMS) in Bristol, who have one of the UK's largest supercomputers, and we'll be using that to run our aerodynamics design through until mid-Jan, early Feb. We want to chase down every last little bit of drag."

Race strategy will be critical. Although the car will carry a five-square-metre silicon solar array to collect energy from the Sun, the rules do permit the vehicle to be charged externally from the mains. But any team that wants to take an energy boost from the grid will also need to compensate by having  more passengers (weight) onboard.

"Teams will be thinking through the permutations. Is it better to charge more often and put more people in; or charge less often and put in fewer people?"

The 2013 event saw a four-seater solar car travel from Darwin to Adelaide with an external energy consumption of only 64 kilowatt hours. In comparison, a modern family car consumes around 56mpg and will have an energy consumption of approximately 5,000kWh.

Solar Team Great Britain wants to be road testing its vehicle come April. The car would then be shipped to Australia in July. The race itself starts on Sunday 8 October. 

"It’ll be a harsh environment - 3,000km through the desert, with the flies and the dust and the heat. But if you want to show you've produced a robust and resilient solar design - that’s the environment you need to go into," Mr Heape told BBC News.