CAL POLY Solar Car
Burt Rutan's earliest involvement with solar cars was also with the university he had once graduated from...

Not quite a practical car, the Cal Poly vehicle was made for racing.

Construction of the car was made possibly through the expert mold machining of Scaled Composites' team.

In the previous Cal Poly Pomona racing car, the students had to almost lie down, and turning corners was difficult.

Type: experimental solar-powered racing car



Powerplant: 8 hp New Generation Motors DC brushless motor

Significant date: 1999

The California Polytechnic University in Pomona, California, is commonly refered to as "Cal Poly Pomona". The Cal Poly Solar Car was a racing vehicle designed and built for the 1999 SunRayce, the premiere solar race held in late June from Washington DC to Orlando, Florida, a distance of 1200 miles. There were 55 other colleges from Canada and the United States entered in the 1999 SunRayce. This project involved over 100 people from various majors. The construction of the car was completed around March 1999. The solar car was designed and created almost solely by students, organized as the Cal Poly Solar Car Club, a collaborative student run and designed project, through which individuals gain "real world" experience in design, construction, teamwork, and management (see insert)

Cal Poly's initial solar car design was a bit impractical. The back of the car was covered with solar cells, but all those solar cells could only produce enough power to run an electric hair dryer (about 1,500 watts), which is not enough energy to run a heavy vehicle. The Cal Poly Pomona solar car was also very light, less than 400 pounds, which is not strong enough to be in traffic and protect a driver in an accident with another car or truck. It was also rather uncomfortable, as students had to climb into the car and almost lie down in it. It also didn't turn corners very well.

What set the Cal Poly Solar Car apart from others was its unique two-motor design. Moreover, the car had the lowest frontal surface area of any solar car built until then. Finally, the car's molds were machined at Scaled Composites, which was a guarantee of excellence and professionalism. "We used 3500 pounds of HD foam, glued together with two-part epoxy to make the molds for our solar car. The foam was CNC'd by Burt Rutan's Scaled Composites in the windy town of Mojave before we actually laid up the Carbon Fiber skins" said David Thompson, President and a founding member of the Cal Poly Solar Car Club. It probably isn't a coincidence that the young Rutan graduated with a degree in aeronautical engineering from Cal Poly.

In the light of these characteristics, it was thought that the Solar Car had an excellent chance at breaking the world speed record for solar vehicles. Yet it cost over a quarter of a million dollars to build, and therefore required much funding, materials and technical help.

Population: 1


Car Weight (w/o driver): 740 lb
Wheelbase: 3.17 meters
Car Height: 1.04 meters
Ground Clearance: 0.35 meters

Body: Carbon fiber
Chassis: Space frame, chrome-moly tubing
Front Suspension: Double A-arm
Brakes: Redundant front disc brakes
Number of wheels: 3 (2 front, 1 rear)
Weight distribution: 60% front, 40% rear

Solar Array
Solar Cells: RWE Solar 16% efficient Silicon single-crystalline
Number of solar cells: 729 cells
Solar Array Power: ~800 W

Motor: New Generation Motors 8 hp DC brushless motor with 96 V controller
Nominal Power Consumption: ~1300W
Regenerative Braking: Hand controlled potentiometer

Batteries: Concord PVX-490T sealed deep-cycle lead-acid
Batteries: 8 12V deep cycle lead acid batteries (40 lbs. each)
Battery capacity: 43Ah, 4.3KWh
Battery pack construction: 8 batteries in series: 2 Packs; 4 batteries per pack
Battery pack voltage: 96V

User Interface: LCD display, switches, foot controlled throttle
12V System: Vicor DC-DC converter 100V(IN)-12V(OUT)
Ventilation Fans
5V System: Data Acquisition, Speed Control Electronics



Main sources:

The Cal Poly Solar Car Team

"Our club is about teamwork, organization, commitment, and the drive to succeed. The club is run like a business. We have design, engineering, publicity, fundraising, and management teams. Like our school's motto, we 'learn by doing.' This 'real world' experience is invaluable in industry and helps ensure that our members get excellent jobs after they graduate. One of the club’s desires, even if we are not some of the top finishers in the race, is to prove our alternative ideas, unique designs, and incorporate them into our solar car. By utilizing these ideas we show creativity and stimulate interest in our car, college, club and sponsors."

The Cal Poly Solar Car Team is one of the most diverse, exciting, and broadening clubs available at Cal Poly. Students aggressively apply what they learn in the classroom to real life design, engineering and manufacturing situations. Partnering with Cal Poly's renowned Mechanical Engineering Department, the solar car club's goals are to educate the public about solar power as an alternative energy source, develop innovative ideas for incorporation in the car, and to allow students to learn and improve teamwork, time management, organizational, design and manufacturing skills.