Here are the results for the Sasol Solar Challenge in South Africa, as at day 3 out of 8. The big storm at the end of day 1 is marked. Only the Challenger class is shown (not the car from Hong Kong, which is driving non-competitively). Black spots mark time penalties, and the photo is from here. See also my teams list and information page, which includes links to team social media.
In the Sasol Solar Challenge, teams drive a fixed route each day, with the option of detouring around a “loop” 0, 1, 2, 3, … times. These “loops” are highlighted in the chart above. For example, on day 1, Nuon and Tokai both drove the fixed route as well as driving the 76.1 km loop five times (however, these “loops” actually happen somewhere in the middle of the day’s route, not at the end).
These “loops” mean that strategy essentially becomes a version of the difficult knapsack problem. Teams must maximise the sum of the lengths of the chosen loops, subject to time and energy constraints. This is further complicated by the uncertainty of future energy input (will it be cloudy in 4 days time?) and the psychological cat-and-mouse between the leaders (something which Nuon generally excels at). It will be interesting to see how Nuon and Tokai play the strategy game over the next 5 days.
Nuon has excellent videos about the race (Dutch with English subtitles) for day 1, day 2, and day 3.
Update: NWU apparently had battery problems. CPUT is still hoping to fix their car so that they can get it off the trailer and onto the road. Days 4 and 7 will see some shorter loops, so some distance might open up between Nuon and Tokai then. Weather forecasts for the race route are:
- Tuesday Sept 25 – Windy
- Wednesday Sept 26 – Sunny
- Thursday Sept 27 – Sunny
- Friday Sept 28 – Rain
- Saturday Sept 29 – Mostly cloudy
Scientific Gems 