World Solar Challenge 2019 Revisited: some additional charts

Revisiting the World Solar Challenge, the chart below shows distance/speed plots for seven WSC teams (for other teams I was either missing some GPS data, or did not have access to explanatory social media). Distances shown are road distances (not geodesic), while speeds are estimated from distance and time information (because speeds were not included in the GPS data that was kindly supplied to me). As a result of data limitations, the compulsory 30-minute stops at Katherine etc. are shown by sharp speed dips, but not necessarily ones that drop all the way to zero.

Vattenfall (3) had a devastating battery fire; Top Dutch (6) were the best new team, finishing 4th; Agoria (8) won the Challenger class; Twente (21) tragically crashed while in the lead; Sonnenwagen Aachen (70) were one of two teams to come back from a serious crash and still finish; Blue Sky (77) were the 11th and last Challenger team to reach Adelaide on solar power; and Kogakuin (88) were the other team to recover from a major crash.

Night stops in the chart above are marked in red. Photos are from their tweet posted minutes before the fire and from a tweet posted shortly afterwards.

Control stop times for Vattenfall: Katherine: Sunday 12:19:21, Daly Waters: Sunday 15:59:21, Tennant Creek: Monday 11:45:23, Barrow Creek: Monday 14:51:01, Alice Springs: Tuesday 9:30:33, Kulgera: Tuesday 12:51:41, Coober Pedy: Wednesday 8:39:31, Glendambo: Wednesday 12:40:58, Port Augusta: Wednesday 16:44:32.

The chart shows Top Dutch’s multiple stops just out of Tennant Creek with battery problems. Top Dutch finished 4th, and won the WSC Excellence in Engineering Award.

Control stop times for Top Dutch: Katherine: Sunday 12:16:27, Daly Waters: Sunday 15:57:03, Tennant Creek: Monday 12:12:55, Barrow Creek: Monday 15:28:35, Alice Springs: Tuesday 10:39:32, Kulgera: Tuesday 14:41:40, Coober Pedy: Wednesday 12:00:43, Glendambo: Wednesday 15:48:50, Port Augusta: Thursday 10:47:39, Adelaide: Thursday 15:30:00.

Night stops in the chart above are marked in blue. Agoria had a virtually perfect race, winning the Challenger class. Visible in the chart after Coober Pedy is the 80 km/h speed limit imposed by the WSC on Wednesday morning after wind gusts caused multiple crashes.

Control stop times for Agoria: Katherine: Sunday 12:17:04, Daly Waters: Sunday 16:05:54, Tennant Creek: Monday 11:55:56, Barrow Creek: Monday 14:56:40, Alice Springs: Tuesday 9:46:28, Kulgera: Tuesday 13:10:50, Coober Pedy: Wednesday 9:22:36, Glendambo: Wednesday 13:05:06, Port Augusta: Wednesday 16:51:59, Adelaide: Thursday 11:52:42.

Twente’s tragic crash (due to a strong wind gust) occurred at about 2165 km from Darwin, just before Coober Pedy. Photos are from a tweet posted the day before the crash and from a tweet posted shortly afterwards. I was one of the people that signed the car after the crash. Twente won the Promotional Award, for their excellent media.

Control stop times for Twente: Katherine: Sunday 12:08:43, Daly Waters: Sunday 15:32:39, Tennant Creek: Monday 11:33:01, Barrow Creek: Monday 14:31:33, Alice Springs: Tuesday 9:17:16, Kulgera: Tuesday 12:40:40.

Sonnenwagen Aachen stopped for five hours to repair their car on Wednesday, just before Coober Pedy, after the car was blown off the road (their first priority was the driver, of course). There was another stop between Glendambo and Port Augusta, due to a broken shock absorber that had been damaged in the crash (Western Sydney Solar Team kindly helped get them back on the road). Sonnenwagen Aachen finished 6th. They also won the Safety Award and and the Spirit of the Event Award (for not giving up).

Control stop times for Sonnenwagen Aachen: Katherine: Sunday 12:27:34, Daly Waters: Sunday 16:09:06, Tennant Creek: Monday 12:17:32, Barrow Creek: Monday 15:12:27, Alice Springs: Tuesday 9:52:06, Kulgera: Tuesday 13:31:00, Coober Pedy: Wednesday 15:08:20, Glendambo: Thursday 9:35:27, Port Augusta: Thursday 14:49:06, Adelaide: Friday 10:03:48.

Blue Sky (Toronto) had several brief stops of a few minutes (including for electrical issues on Monday), but no particularly dramatic events. They were also slowed somewhat by clouds on Wednesday morning. Blue Sky finished 11th (the last Challenger team to reach Adelaide on solar power).

Control stop times for Blue Sky: Katherine: Sunday 12:49:29, Daly Waters: Monday 8:03:38, Tennant Creek: Monday 14:42:34, Barrow Creek: Tuesday 9:54:44, Alice Springs: Tuesday 14:23:40, Kulgera: Wednesday 11:00:30, Coober Pedy: Thursday 10:34:55, Glendambo: Thursday 15:01:18, Port Augusta: Friday 10:53:25, Adelaide: Friday 15:47:10.

Kogakuin was forced to stop with an overheated motor just after Katherine. They also crashed twice due to strong winds. The second, more serious, crash was due to a mini-tornado or willy-willy just before Glendambo (see their report here), and required overnight repair in town on Wednesday night. Kogakuin finished 5th. They won the CSIRO Technical Innovation Award, for their hydropneumatic suspension. Their dramatic after-race video is here.

Control stop times for Kogakuin: Katherine: Sunday 12:18:43, Daly Waters: Monday 8:03:13, Tennant Creek: Monday 13:16:26, Barrow Creek: Monday 16:15:52, Alice Springs: Tuesday 11:03:53, Kulgera: Tuesday 14:32:15, Coober Pedy: Wednesday 12:04:23, Glendambo: Thursday 9:45:18, Port Aug: Thursday 14:18:47, Adelaide: Friday 9:53:00.

For comparison, here is the distance/time chart I did before. In that analysis, higher means slower, and the arrival times (in Darwin time) can be read out on the right:


Farewell to the World Solar Challenge

This ends my World Solar Challenge 2019 coverage. I will begin covering the American Solar Challenge in a few months. Meanwhile, regular science content resumes.

Summary of WSC additional awards:

  • CSIRO technical innovation award: Kogakuin, for their hydropneumatic suspension.
  • Safety award: Sonnenwagen Aachen, who crashed.
  • Spirit of the Event award: Sonnenwagen Aachen, for not giving up.
  • Promotional award: Solar Team Twente, for their excellent media.
  • Excellence in engineering award: Top Dutch, for their wonderful car.

World Solar Challenge race chart 4

Another race chart (I’m using the same baseline speed I used in 2017). The right vertical axis shows arrival time at “end of timing” in Darwin time (Adelaide time is an hour later).

After repairs, Kogakuin and Aachen have reached Adelaide, followed by Antakari, Nagoya, Eclipse, and Jönköping University. Blue Sky are in Adelaide, but do not seem to have crossed the ceremonial finish line yet.


World Solar Challenge race chart 2

Another preliminary version of my race chart (I’m using the same baseline speed I used in 2017). The right vertical axis shows arrival time at “end of timing” in Darwin time (Adelaide time is an hour later).

Tragedy for front-runner Twente (story here) and for Kogakuin and Sonnenwagen Aachen (although Aachen is back on the road and Kogakuin hope to be so too). The Belgians are closing in on Vattenfall.

In the Cruiser Class (not shown), there are only 3 non-trailered teams.

On a personal note, Scientific Gems is now in Adelaide!


World Solar Challenge race chart

A preliminary version of the race chart I did in 2017 (non-trailered Challengers only). I’m using the same baseline speed I used in 2017, although the front-runners are much faster this year. The temporary problem faced by Kogakuin and the longer-term battery-overheating problem of Top Dutch are clearly visible.


World Solar Challenge car dimensions

The charts above and below (click to zoom) show the dimensions of some of the Challenger-class cars in the World Solar Challenge coming up this October (see also my illustrated teams list). In the chart above, ⬤ = cars with silicon arrays (4 m2 allowed), ⬛ = thin film single junction (3.56 m2 allowed), and ▲ = multijunction gallium arsenide (2.64 m2 allowed). All three technologies are in use this year. Hollow symbols denote cars from 2017.

Particularly noticeable is Twente’s incredibly shrinking car. They switched technologies this year, but were also so efficient that their new car is about 18% smaller than Delft’s – almost a square metre smaller! There are also three visible clusters – larger silicon-array cars at the top right, compact catamarans (like Twente and Delft) at the left, and monohulls at the bottom right. In the chart below, solid lines show dimensions for this year, and dotted lines those of 2017.

Update: the width of Eclipse’s entry has been corrected (the impact attenuator has been removed for WSC).


Another quick solar racing update


Four recently revealed vehicles: Top Dutch, Twente, Blue Sky (Toronto), and Kogakuin

In recent solar car news, we have now seen new car reveals from HUST (pic), Top Dutch (video), Twente (video), Blue Sky (video), the commercial solar car Lightyear One (video), Kogakuin (video), and – just now – Agoria (video and below).


The new car from Belgian team Agoria (photo credit)

Promised new car reveals include Eindhoven4 July, HK IVE6 July, NIT6 July, Vattenfall16 July, Michigan19 July, Aachen22 July, and JU30 August. I will continue updating my list of teams as news and pictures come in.


Esteban were first to get all greens in scrutineering for FSGP 2019

Meanwhile, 18 teams – Kentucky, Florida, CalSol (1st in 2017), Northwestern, Mich St, Illinois St, Illini, Waterloo, Principia, Ga Tech, Esteban (3rd in 2017), SIUE, Calgary, Rutgers, NJIT, NCSU, W Mich, and UPRM – are at FSGP 2019 right now. Esteban were first to get all greens!


World Solar Challenge: about the Cruisers

To illustrate the World Solar Challenge Cruiser-class scoring for 2017, here is the calculation for Kogakuin’s 2015 car (above). Disclaimer: this is, of course, my personal interpretation of the regulations.

Notice that Cruisers are not in a race this year – any arrival time during the 11:00 to 14:00 time window on Friday is OK.

Arrival time

Friday 11:35.
Inside window? YES

Energy efficiency

Battery capacity, Q = 14.855 kWh
Number of recharges, n = 1 (at Alice Springs)
External energy use, U = (n + 1) Q = 29.71
Person-km, C = 3022
Energy efficiency, E = C / U = 101.7
Highest energy efficiency, E* = 203.6 (Eindhoven)
Relative energy efficiency, E / E* = 0.4996

Practicality

Practicality P = 51.75
Highest practicality, P* = 84.5 (Eindhoven)
Relative practicality, P / P* = 0.6124

Total Score

Total score, S = 80 E / E* + 20 P / P* = 39.97 + 12.25 = 52.22

This is a massively lower score for Kogakuin than was actually awarded in 2015. This year, the World Solar Challenge Cruiser Class is all about energy-efficiency, carrying passengers, and practicality. Expect to see the four-seat and five-seat Cruisers (like the Polish car below) running with every seat occupied.


World Solar Challenge: dark horses

Recently I made a poster of the favourites (based purely on 2015 performance) for the 2017 WSC. Here is a somewhat more subjective list of new, innovative, and rising teams. All worth watching! For more details, see my annotated list of teams.


World Solar Challenge: Challenger dimensions

MostDece has written a superb blog post on the WSC challengers. Based on that, I’ve updated my previous post on dimensions. The infographic above (click to zoom) shows the reported length and width of 16 WSC cars (Challenger class only, this time). The widest car (at 2.05 m) is the South African car from NWU (below), but of course that includes the outrigger wheels. The narrowest is the long narrow bullet car from Michigan. There are also short zippy little cars from Nuon, Principia, and Punch.

Update: The chart below clusters cars with similar length/width combinations. NWU is a visible outlier. Below NWU, we have big cars (ITU, MDH, Adelaide, Aaachen, JU – over 1.6 m wide and at least 4 m long), short catamarans (Nuon, Principia, Punch – 1.55 to 1.6 m wide and at most 3.5 m long), narrow catamarans (Nagoya, Stanford, Twente, WSU – 1.38 to 1.5 m wide and at least 4 m long), and monohulls (Tokai, Kogakuin, Michigan – at most 1.2 m wide and over 4.9 m long):

Update: Unfortunately, the two charts above reflect incorrect information from the Stanford team. The Stanford car is actually substantially wider.