To drive the Stuart Highway, the 3000km stretch of road which runs between Darwin in the north of Australia and Adelaide in the south, is a test of the endurance of any vehicle. For the World Solar Challenge, the objective is simple: to complete this route in a little over 6 days, using only energy collected from the sun. As an undergraduate starting university in 2007, I had little doubt that to be part of a team which would compete in this event was an opportunity I couldn’t afford to miss.
A little under four years later, I flew out to Darwin with 11 other recently graduated engineers from the University of Cambridge for the 2011 Veolia World Solar Challenge. By this point our team had already built a car which had competed in the 2009 race (the World Solar Challenge is run every two years), and we were using the same car again although we had made several significant changes. In 2009 the car had suffered major problems with its battery and the reliability of the electrical systems, so we had fixed these issues and also made major aerodynamic improvements to the canopy and wheel fairings. Nonetheless, we knew that the build quality of Endeavour MkII was not good enough for us to be able to match the top teams – our aim was simply to complete the race.
Five weeks in Darwin saw us complete all the tasks we needed to prepare Endeavour, and also complete over 400km in testing. There were a few late nights, but the work on the car went largely to plan. My main responsibility was to organise the logistics – freighting of the solar car, arranging hire cars, accommodation, budgets for food and fuel, planning when to do testing and scheduling the work on the car, etc. As it turned out this was where we had the most problems, but when you’re doing everything on a strict budget and have never dealt with some of the systems before this isn’t really surprising. In my defence, most of the issues were due to unforeseen events and you just have to deal with them as best as you can. When an airline loses all your sponsors’ logos three days before the start of the race, you find somewhere in Darwin to print them that same day for the same price you paid in the UK. And when another driver crashes into your hire car, you don’t let the $3300 excess charge from the hire company ruin your race – you scrape together the money from whatever you have available. Somehow, in the end, everything worked out okay.
Seeing the solar car drive on the road for the first time is the best thing ever – especially when it just works. Solar car racing is never really going to be an exciting spectator sport, so sitting in cruise control at 60kph a few hundred metres ahead of Endeavour as she drives through the Australian outback is actually quite relaxing. As long as she keeps working there’s not actually that much else you can do, and if we had one advantage it was at least that Endeavour MkII was reliable. So testing was a great boost to our confidence, and having sorted out one or two niggles we could see that things were starting to go well.
Of course, we had some time to relax away from work on the car as well. We wouldn’t have been doing any of this without the support of our sponsors and so we are very, very grateful to everyone who has supported the team. BOC provided us with a workshop at their facility in Darwin, and the staff there were unbelievably generous to us. Their manager, Harry, invited us for barbeques at his house and Hendrick took us for a day out at Lichfield National Park. Moreover, they had plenty of advice about how best to adapt to the climate in the Northern Territory and what we would need to survive during the race – invaluable for making sure we could perform as best as we could.
On Sunday 16th October, 37 solar cars rolled out of Darwin on their way to Adelaide. We had qualified low down in 30th, but we didn’t care – our aim was to complete the race and our qualifying result wasn’t going to change the outcome in that respect. For the first two hours Endeavour cruised seamlessly at 60kph towards Katherine, the first control stop. But as we came to do our first driver change an electrical problem caused the car to cut out completely. My first reaction was one of distress – it was the first time Endeavour MkII had broken down unexpectedly. You know almost instantly that it’s a dodgy connection somewhere, and stuck at the side of the road it could take hours to detect and resolve it. It was fixed in little under an hour by changing our steering wheel to an old model – and unwanted setback, but not a disaster.
At this point we made our only bad decision of the race. A fault in our chase car (the car which follows the solar car) meant we didn’t have any telemetry data about how much power Endeavour was using and we decided to drive at a speed which would allow us to reach the Katherine control point on time. Unfortunately this wasn’t sustainable, and we soon drained the battery. Still needing to maintain progress, we had no option but to trailer the car. It was very demoralising for all. As our first day of proper solar racing, at least one mistake should have been expected.
Thereafter, the race went well for us and we would have been able to continue driving for the rest of the time on solar power had conditions not conspired against us. We might not have quite completed the rest of the race distance, but we would have come close. Monday morning saw good sunshine, but the afternoon brought cloud and thick haze from a large bushfire – a dramatic site to see such a wide plume of smoke rising from the ground – and we were again forced to trailer towards the end of the day. Tuesday brought a full day of driving on solar power, albeit aided by a four hour stop due to more bushfires on the road, which enabled us to almost fully recharge the battery. On Wednesday Endeavour again drove well, but the continued haze meant that progress was slow and so we eventually trailered to Alice Springs.
By this point in the race, we all knew exactly what we were doing and our teamwork was flawless. The race only allows us to drive between 8am and 5pm, but we would always be up before dawn and have camp cleared long before 7am. This gave us plenty of time to trailer Endeavour back to her starting point for the day, and to point the array directly at the sun right up until we were ready to start driving. Each day our scout van, driven by Henry and Oli, would often race ahead to replenish our fuel and water supplies – they did an excellent job and we always had plenty of whatever we needed. The team members in the lead and chase cars, which must always be either side of Endeavour, worked hard to keep track of our progress, to decide what speed to drive at and to provide the solar car driver with encouragement and information. The solar car is cramped, and with no air conditioning the temperature can easily reach 40oC in Australia, so driving Endeavour is by no means comfortable. As for me, I spent most of the time driving our trailer vehicle – a brand new Discovery 4 generously lent to us by Jaguar LandRover. It was a hard life for some!
Thursday saw more great progress until the afternoon when the sky clouded over and it eventually started to rain. We can’t drive Endeavour in the rain – not least because the driver can’t see – and so we trailered to a small resting place called Cadney Homestead. As we arrived the rain had turned to thunder and lightning, and by now most of teams had also been forced to trailer. That evening there were more than 10 teams who had all stopped at Cadney – an impressive site for what is normally a deserted truck stop.
The sky on Friday was completely overcast, but with some charge left in the battery we drove on until we had drained it completely. It was not until Saturday morning at 11am that the sun came out again, and after a brief stop to give the battery at least some charge we drove the rest of the distance to Port Augusta. By this point the roads are starting to get busier, and so the police don’t allow us to drive between Port Augusta and Adelaide after 11am on the Saturday. This meant we knew we had no reason to conserve energy and so driving directly from the midday sun we averaged 80kph for the final 120km to Port Augusta. At least it was a positive note on which to end our solar driving.
In Adelaide, the display in the main square and the awards ceremony were great events to be part of. It was also one of the last chances to meet up with the members of the other teams, many of whom we had made friends with in Darwin and along the route – all the participants in the World Solar Challenge are certainly highly motivated about what they do. We finally finished in 25th position having completed 1487km under solar power, but the numbers do not reflect the full story. Only 7 teams completed the full race distance.
As we look to the future, we maintain our strong ambition to win the race, but we know that we are not going to be able to compete with the top teams at their own game. We have made significant progress in developing a concept for a vehicle which will be more relevant as a practical mode of transport, and this fits in well with the ideals of the event. Many of the team will remain at Cambridge to complete their PhD and so we will be able to provide good continuity to the younger members of the team.
I myself am not continuing at university, but I shall remain involved with the team as best as I can. Was the World Solar Challenge an opportunity not to be missed? Definitely.