In 2013, a group of engineering students from Eindhoven University of Technology designed Stella, a four-passenger solar-assisted electric vehicle (SAEV) that won the biannual Bridgestone World Solar Challenge (Cruiser Class). Two years later, the team returned to the Australian competition with its updated Stella Lux, and won it again by traveling 1500 km (932 miles) on a single charge. In 2017, the team cruised to a "three-peat" with its five-person Stella Vie. With nothing left to prove on the competition circuit, five alumni of Team Eindhoven are now developing a commercial SAEV that's based on the Stella family design. If all goes as planned, the Lightyear One should be in the driveways of a few early adopters sometime in 2019.
Lightyear One
According to the company's promotional video, fossil-fueled vehicles travel a combined 9.5 trillion kilometers - about one lightyear - every year. With a mission of "traveling the distance of a lightyear using only solar energy," the company dubbed itself Lightyear and named its first model the Lightyear One. Needless to say, the company is keeping mum on the technical details of the car, but since Lightyear One is based on the Stella series, which I reviewed back in 2015, we can assume many similarities. Based on that review and the Lightyear One FAQ page, let's run some numbers.
Battery Capacity
When fully charged, Lightyear One can travel up to 800 km (~500 miles) on battery power alone. The car can be recharged from a standard household outlet, where one hour of charging (@ 3.7 kW) will deliver 40 km (25 mi) of range. An hour at a 10kW EV charging station will provide 110 km (68 mi), and the same time at a fast charger (75 kW) will give Lightyear One 850 km of driving distance. Those numbers tell us that the car's battery has around 70 kWh of capacity and its "fuel economy" is 11 km/kWh. By comparison, a Tesla Model 3 with a 75 kWh battery bank has a range of 500 km (310 mi), or 6.7 km/kWh.
Solar Charging
The solar panels integrated into the Stella Lux provided 1.5 kW of peak power. Assuming similar output on the commercial version, we can calculate that one hour in the sun adds 16 km (10 mi) to Lightyear One's range. A clear day in a sunny location might add 90 km (56 mi) to the drive. The team estimates that sunlight alone can provide up to 10,000 km of annual driving range in Amsterdam, 14,000 km in Chicago, and 20,000 km in Honolulu. (If they'll pay my expenses, I'll be quite happy to verify that last number experimentally.) Lightyear claims that in a sunny climate, one can drive the car for months on solar power alone. I suppose that's true for those who drive less than 80 km (50 mi) per day and whose cars are parked outside in direct sunlight. Most commuters drive less than half that distance to work every day, so even partly sunny locations would probably suffice.
Eco-Friendly Design and Manufacturing
With internal combustion engines, the overwhelming majority of a vehicle's carbon footprint is due to burning fuel. The carbon footprint of driving an EV depends on the source of electricity. In either case, however, manufacturing the car also uses energy and releases CO2 into the atmosphere. Lightyear is working with its vendors to ensure that materials are as "green" as possible. Although carbon fiber composites are generally considered non-recyclable, Lightyear is pushing its suppliers to deliver composites and solar cells that can be recycled.
Availability and Cost
Lightyear is taking preorders for ten vehicles to be released in 2019; another hundred are set to roll off the assembly line in 2020. The company says that they'll be available in the EU and the US.
Remember when Tesla released its first car, the Roadster, at a price of $112,000? Obviously, that vehicle wasn't meant for the average consumer, but it gave the company a starting point. Nine years later, Tesla started taking orders for its affordable Model 3, which is within reach of most car buyers. It looks like Lightyear is going down the same road, as it were, with an initial price tag of €119,000 ($145,000US) for Lightyear One. If you'd like to calculate the payback period on that - based on purchase price, fuel, and maintenance costs - you can use the EV vs ICE spreadsheet that I created.
I love the concept, but at that price, the Lightyear One is more of a status symbol than a practical car. That's okay, though, because that's what the Roadster was a mere decade ago. When the status-seekers buy the first models, Lightyear will start to build the cash flow and the experience to develop a more affordable vehicle for the rest of us. I predict sunny days ahead in the EV industry.
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