European Solar Challenge results

The iLumen European Solar Challenge is over. Challenger Class results are shown above, and Cruiser Class results below. The heights of the bars show points allocated in the various categories. Twente was third overall on points in the Challenger Class, although a very close second in terms of laps (344).

A number of teams had some unfortunate problems, and the Cruisers from Eindhoven and PUT Solar Dynamics were not able to hit the track at all. For pictures, see team social media (see my list of teams) or iESC social media at        (click on the icons).

Update: see also this lap chart.

The Cannonball Sun

Something a little different in the solar car space today. Will Jones and Kyle Samluk are mechanical engineering students from two different universities in Michigan, with a background in a high school team. Eschewing the mainstream competitions (as many major teams are doing), they have built their own solar car, and between 22 June and 6 July they are planning to drive it the 4,900 km or so of the Cannonball Run from New York to Los Angeles.

The US has been crossed in a solar car before (in 2012), when Bochum’s SolarWorld GT made its round-the-world trip. It clocked up a scenic 6,553 km in just over 50 days, from San Francisco via Dallas to Charleston, SC, requiring frequent charging stops and additional solar panels in the trunk. Will and Kyle, assisted by fellow-student Danny Ezzo, hope to cross the US in less than a third of the time. You can follow their progress on their website and on Instagram or Facebook. They are also raising funds needed for the trip.

Top L: Pink Skies with aerobody but no solar panels, Top R: Pink Skies with solar panels but no aerobody, Bottom L: chassis, showing tadpole wheel configuration, Bottom R: rear (driven) wheel [images from the Pink Skies team].

The chassis of their car Pink Skies is a monocoque made from sheet aluminium, with bulkheads riveted in (it looks more like an Abrams tank than an aircraft, to be honest). The solar panels appear to be originally intended for rooftop use. They make up about a third of the weight, but produce a substantial 2.2 kW of power (roughly double that of a typical ASC or BWSC car).

For energy storage, Will and Kyle have taken the safer LiFePO4 option. The suspension is pretty much missing in action, so the ride is likely to be somewhat bumpy. Top speed appears to be an impressive 110 kph, with a 70 kph cruising speed. Will and Kyle also seem to have done a good job of engineering on-the-fly as testing revealed problems with the initial design. I salute their initiative and their vision and I wish them well as they drive across the American continent.

Solar Racing Basics: Chassis

Click to zoom / Image credit: American Solar Challenge

Continuing the analysis of my Solar Racing Basics Poster (see this tag), solar cars have to keep their driver safe and the vehicle in one piece. There are two basic ways of doing this. First, a car can have a carbon-fibre-reinforced polymer body over a metal chassis. For example, Bochum’s thyssenkrupp blue.cruiser (below) is supported by a tubular frame of ultrahigh-strength steel. Second, a car can have a load-bearing “monocoque” body, possibly also of carbon-fibre-reinforced polymer. Carbon-fibre-reinforced polymer is strong for its weight, and this is significant, since a noticeable amount of energy in a solar car (though less than aerodynamic drag) is lost in rolling resistance. The rolling resistance of a car is proportional to its weight (it also depends on the quality of the tires), and so reducing weight makes the car faster. In 2019, the lightest solar car (from Western Sydney) weighed just 116.8 kg without the driver.

Cars may include a “roll bar” or “roll cage” to protect the driver in addition to the monocoque body. This “roll bar” or “roll cage” may be made of metal tubes, or it may also be made of carbon-fibre-reinforced polymer. A close look at unpainted carbon-fibre-reinforced polymer shows the “chequerboard” pattern of carbon-fibre “cloth” embedded inside transparent epoxy polymer (as in the body and roll bar of Durham’s Ortus, also below).

Click to zoom / Image credits: Anthony Dekker (Bochum’s thyssenkrupp blue.cruiser and the interior of Durham’s Ortus)

To read more, see see this post about car body and chassis by Nick Elderfield of the University of Calgary Solar Car Team, this Instagram post about composite materials by MIT Solar Electric Vehicle Team, and this UMNSVP wiki on Composite Chassis Design.

Solar Buggy aftermovie!

Credit (click image to zoom)

Hochschule Bochum is famous for their Cruiser-class solar vehicles. But they also have a solar buggy team   ). In 2019, they attempted a world record for crossing the Simpson Desert. Things did not go entirely according to plan, thanks to unusually high temperatures and strong winds, but they certainly produced a fantastic, innovative vehicle.

A few days ago, they released a spectacular 100-minute aftermovie of their world record attempt (see the 3-minute teaser and the full aftermovie). Well worth a look!

European Solar Challenge: update #3

Below (click to zoom) is my latest guess at the field of cars for the 24-hour iLumen European Solar Challenge to be held at Circuit Zolder in Belgium on 18–20 September (Durham has, sadly, withdrawn from the event). All car photographs except the Swiss one are mine (taken at WSC). See this page for team details and further iESC information.

In other sad news, we might see some rain during the race. One a more positive note, most teams have been getting in some driver practice.

Below are some pictures from recent social media of five teams (use the picture above to identify teams):

Breaking news: in a sad turn of events, Bochum are out of the Cruiser class, as are Lodz. This leaves only Eindhoven in the Cruiser class. See the current teams list here.

My Personal WSC Gem Awards Part 2

The reliability gem goes to team 11 (Bochum University of Applied Sciences). Their thyssenkrupp SunRiser has clocked up over 16,000 km, I understand. It drove the entire 3022 km of the World Solar Challenge in 2015, and again this year. It came 3rd at iESC 16, 2nd in the iESC 18 Cruiser class, 7th at Albi Eco 18 (with 100 laps), and 2nd at Albi Eco 19 (with 119 laps). And it’s still the sexiest Cruiser-class car around.

The disco lights gem goes to team 40 (Eindhoven). Eindhoven also scored highest on Cruiser-class efficiency, carrying an average of 2.63 people for 71.24 kWh of external energy. The car also has an understated elegance. And the disco lights serve a serious purpose: they show battery charge, and the ability of Stella Era to act as a mobile charging station.

And a special best use of tape gem goes to team 88 (Kogakuin), with team 70 (Sonnenwagen Aachen) a close second.

World Solar Challenge September 3 update

In the leadup to the 2019 Bridgestone World Solar Challenge in Australia this October, most cars have been revealed (see my recently updated illustrated list of teams), with JU’s reveal a few days ago (see below), and Tokai’s reveal due in a few hours.

There are now 9 international teams in Australia (more than the number of local teams). Eindhoven (#40), Agoria (#8), and part of Vattenfall (#3) are driving north to Darwin, while Top Dutch (#6) have a workshop in Port Augusta (and living quarters in Quorn).

JU’s solar car Axelent (photo credit)

The chart below shows progress in submitting compulsory design documents for the race. White numbers highlight eight teams with no visible car or no visible travel plans:

  • #86 Sphuran Industries Private Limited (Dyuti) – this team is probably not a serious entry. I will eat my hat if they turn up in Darwin.
  • #63 Alfaisal Solar Car Team – recently, they have gone rather quiet, but they have a working car.
  • #89 Estidamah – they have not responded to questions. They also might not turn up, although they have obtained several greens for compulsory documents.
  • #80 Beijing Institute of Technology – they never say much, but they always turn up in the end. I don’t expect this year to be any different.
  • #4 Antakari Solar Team – they are clearly behind schedule, but they are an experienced team. They will probably turn up. (edit: they have revealed a beautiful bullet car)
  • #55 Mines Rabat Solar Team – they seem to have run out of time. Can they finish the car and raise money for air freight? I’m not sure. (edit: it seems that they will attend the Moroccan Solar Challenge instead of WSC)
  • #98 ATN Solar Car Team and #41 Australian National University  – these teams are obviously in trouble but, being Australian, they should still turn up in Darwin with a car. (edit: both teams have since revealed cars)

World Solar Challenge late August update

In the leadup to the 2019 Bridgestone World Solar Challenge in Australia this October, most cars have been revealed (see my recently updated illustrated list of teams), and the first few international teams (#2 Michigan, #3 Vattenfall, #6 Top Dutch, #8 Agoria, and #40 Eindhoven) have arrived in Australia (see map above). Bochum (#11), Twente (#21), and Sonnenwagen Aachen (#70) are not far behind. Eindhoven (#40) are currently engaged in a slow drive north, while Top Dutch (#6) have a workshop in Port Augusta (and living quarters in Quorn).

Meanwhile, pre-race paperwork is being filled in, with Bochum (#11) and Twente (#21) almost complete. Sphuran Industries from India (#86) is not looking like a serious entrant. On a more positive note, though, Jönköping University Solar Team (#46) is revealing their car later today!

Solar car map of the Netherlands plus borderlands

Below (click to zoom) is a solar car map of the Netherlands (north, south, east, west), plus the German cities of Aachen & Bochum and the Belgian city of Leuven, which are close enough to the Dutch border to be in the map region. That’s 7 solar car teams in a very small corner of the world! (base map modified from one by Alphathon).

World Solar Challenge: current activities

Four representative solar car team activities in the lead-up to the World Solar Challenge in October – Top left: Cambridge revealed their Cruiser on 15 August (photo: Nigel); Top right: Solar Team Eindhoven packed up their Cruiser for air transport to Australia, as also did Top Dutch (photo: Bart van Overbeeke / STE); Bottom left: Agoria Solar Team (Belgium) did some final testing at Beauvechain Air Base in less than perfect weather (credit); Bottom right: Bochum SolarCar Projekt is staring at a map as their container slowly travels to Australia by sea – the ship was expected in Fremantle today, en route to Melbourne and Sydney (credit)