What an exiting adventure! After more than two years of hard work and a 3000 km race through the Australian outback, our Huawei Sonnenwagen made it across the finish line in Adelaide.
The last months were full of new challenges, teamwork, emotions, surprises and sleep deprivation. Since time has gone by very quickly lately, it is time to recap our trip to Australia.
The weeks before the race
The first few members of the team arrived in Darwin at beginning of September, just a few days before the planned arrival of the solar car. Being accommodated in one of the largest (and loudest) hostels in the city, we had trouble to stay concentrated to get the necessary paperwork done that was necessary to get our car through the customs and the biosecurity checks at the Australian boarder. Luckily, the local Charles Darwin University provided us with a number of calm and air-conditioned offices.
Shortly after we managed to leave the Darwin harbour with our solar car, we were joined by the second group of team members. At the same time, we moved into our own little work shop that was kindly provided by a local car dealership.
We spent the last few weeks before the race start with testing and tweaking our solar car, finalising our telemetry and driving strategy system and preparing the camping equipment and our convoy vehicles. None of us would have expected how many technical and logistical challenges there were still left for us to master so close before the race. Not only did our urgently needed tires get stuck in the customs control in Brisbane, but we also had a few major problems with our solar panel wiring, the battery charger, one of our driving strategy computers and a number of other components. After a series of sleepless nights and due to surprisingly fortunate circumstances, somehow everything turned out well and we made it to the start line just in time.
Race day 1
Unlike the troublesome days before the race, we did not have any urgent technical problems during the first race day. The weather was only a little cloudy, the telemetry systems constantly and without interruption reported the good state of all components and, unlike many of our competitors, our solar car handled beeing passed by huge road trains easily without leaving its lane. During the first hours, we were overtaken by a few more experienced teams. We kept our speed low, so that we could save battery for the bad weather that was predicted for the following days. Right in time at 5 pm, we found an appropriate camping spot, set up our equipment and inclined the solar panel to catch the last remaining sun light. Even though we noticed the solar panel output to be slightly lower than expected, we could not find an obvious fault. Unfortunately, we also could not carry out any tests after the sun was gone. While a few people were still working on the car to prepare for the next race day, the rest of the team prepared dinner. The air was still very hot and we were surrounded by large and strange insects but all of us fell asleep in no time.
Race day 2
In the morning of the second day, we noticed that one of our maximum power point trackers did not work as expected and identified a slack joint as the problem. Even though the fault could quickly be fixed, we probably lost a bit of precious energy. Only a few minutes after we continued our trip, the car suddenly stopped driving. Within a very short time, we managed to identify a cable rupture as the cause and could luckily fix it within a few minutes. Unlike our trailer and one of our support vehicles that both had a flat tire during that day, our Sonnenwagen could make it through the day without further issues. Unfortunately, our battery drained much quicker than predicted at the end of the day due to cloudy weather and, even worse, our driving strategy system predicted a serious energy shortage for the next few days. We slowly realised that we might not be able to reach all control stops and went to bed with mixed feelings.
Race day 3
The third day of the race went by really quickly and without any technical problems. As predicted, the weather started to get worse around noon and our battery started to drain in a ominous speed. We managed to get to our camp spot in the evening as expected but with almost no charge left in the battery. We expected not to be able to keep the minimum speed during the next day and hence be excluded from the race. By this time, more than one half of all cars that started from Darwin already had been excluded from the race due to technical reasons or because they could not maintain the minimum speed.
Race day 4
We woke up early in the morning on the fourth day because it started to rain heavily and the winds got really strong. We decided to dismantel our camp to protect our equipment and the solar car. As we left our camping spot in the rain a few hours later, we had almost gained no additional energy from our solar panel. We also had a long and steep hill ahead of us and had only little time left to reach the next control stop in Alice Springs, 1500 km away from the start line in Darwin. Consequently, we expected the solar car to shut down every moment while trying to maintain the minimum speed.
It was just in this moment that we got a call on our satellite phone from one of our team members who already was in Alice Springs. We were surprised to hear that the opening times of the control stop had been extended by two hours due to bad weather, enabling us to reach the next control stop in time easily. In Alice Spring, we were welcomed enthusiastically by our team members and a large crowd of spectators. It was incredible to see that the clouds suddenly disappeared after we left the control stop. Until we reached our campsite, the road led us through an amazing landscape and our battery was finally gaining charge again. Except for a small shower of rain in the evening, the weather forecast predicted a cloudless sky for the next days. Nevertheless, we knew that we would have to maintain a relatively high speed throughout the next day to reach the control stop in Coober Pedy in time.
Race day 5
At the fifth day of the race, the solar car worked like a charm and the solar panel output was even better than expected. Since the weather forecasts predicted a slightly clouded sky in the late afternoon and our driving strategy model warned us about possibly running out of charge before the control stop. That was why we decided to go with the minimum possible speed to reach Coober Pedy in time. Unfortunately, the battery ran out of charge just a few kilometers away from the control stop so that we missed the opening times by a hair. Even though we were excluded from our race class because of this, we were more than happy to end up as the best newcomer team.
Race day 6
In order to get to the victory ceremony in Adelaide in time, we were supposed to put the solar car on our trailer for a distance of about 200 kilometres. Since the weather was really good and we were very pleased with the performance of our solar car, we decided to put it on the raod again for the last few hundred kilometers until the finish line. Due to the good weather, we could easily go more than 80 kilometres per hour on average and reached the beautiful city of Adelaide in short time. No words can decribe how good it felt to cross the finish line and take the obligatory bath in the fountain at Victoria Square.
The next challenge: Getting ready for the next World Solar Challenge in 2019
The whole team is determined to accept the challenge again in 2019, when the next World Solar Challenge in Australia will take place. The development of the next car will be focussed on testing of the components and the solar car's aerodynamics and weight. We are very confident that we will be able to use our experiences from the first race to make it to the top next time.