June 24, 2020

The Lightyear story: How the start inspired the endgame

Arjo van der Ham


Chief Technology Officer (CTO) — Co-founder

The Lightyear story: How the start inspired the endgame

How it all began

For me, Lightyear started in March 2012, when I got a call from Lex, who I vaguely knew from the speed skating association, asking me to join his ‘secret project’. One and a half year later, we were celebrating our victory as winners of the Cruiser Class of the World Solar Challenge with Stella - ‘The World's first Solar Powered Family Car’— a sentence I can now say in almost as many languages as I can order a beer :)

At the core of Stella’s design was the scoring formula the organisation had published. It gave you one number to optimise towards to maximise your chance of winning. Of course, there were rules to follow, but the cool thing about it was that the design process could be treated as a mathematical 'constrained optimisation' problem. The objective function is the scoring formula, the rules and regulations are the constraints and all the design decisions you have to make are the variables. — more on this later.

A closer look of the solar powered roof at the Stella world solar challenge
Arjo looks at the solar roof of Stella — the solar car that participated in the World Solar Challenge of 2013. © Photo by Bart van Overbeeke.

Dreaming of Changing the World

The World Solar Challenge and all the events with the car after that showed us how much impact a small team could have on this world. And it inspired us to somehow use our skills to make this world a better place. The first question we asked ourselves: what is the biggest problem in the world right now? According to millennials surveyed by the World Economic Forum, it is climate change. Our next question then became, what causes Climate Change and how can we use our skills to help solve it?

We looked at many different ideas, from floating solar to electrifying containerships and we took another look at solar cars. We concluded that the four main trends in the automotive industry - shared mobility, autonomous driving, electrification and connected cars - would eventually converge into a robotaxi concept. Those robotaxis will be able to operate against extremely low cost per person per mile, because the biggest cost drivers would come down significantly: Purchase price can be divided over many more miles due to higher utilisation, the driver is replaced by the autonomous system, and electricity is much cheaper than gas ¹.

The missing piece in this future concept is the energy source. How will all those cars be charged, and how can we guarantee that the electricity is generated in a sustainable way?

Detail of the solar roof of the Lightyear One prototype

The endgame, and how to get there

That's where the solar car comes into play. Take the aforementioned robotaxis, but now drastically reduce their energy consumption and add a solar panel such that they can be charged using the two energy sources that are available almost anywhere on earth: the sun and domestic outlets. That way, we don’t also have to install 1 billion high power charging stations worldwide.

The solar robotaxi now has the potential to become the cheapest form of mobility, it could (and should!) even outperform 20-year-old combustion cars. That’s how Lightyear will reach its mission: Clean mobility for everyone, everywhere. By making sure that the cheapest form of mobility is also clean.

Of course all of this is still a couple of years away, and autonomous driving has a long way to go before becoming mainstream, so what is Lightyear doing in the meantime? That strategy evolved around two main challenges Lightyear needs to solve to be successful in that future: We need to establish a brand, and we need to get the technology for efficient cars mature enough to be cost competitive. The development of the Lightyear exclusive series and the high volume series car are the two products that will get us there.

Technology that needs to be further developed

In the beginning we talked about tackling engineering as an optimisation problem. Unfortunately, this problem doesn’t (yet? :)) have a solution that is guaranteed to lead to the global optimum. However, by studying the problem (read: making concept trade-offs), we can evaluate the effect of design decisions on the performance of the product. For example: we can study how much influence a bigger solar panel has on the total cost of ownership of the vehicle. In general, we can determine which systems have the biggest impact on the car. Also, we can study different architectures (using in wheel motors vs. on board motors for example). From the combination of these analyses we can determine which new developments will bring a significant advantage to the product performance. In case of the Lightyear One, those ‘core technologies’ are the solar panel, the in-wheel motors, the thermal management system and aerodynamics.

Because of their huge combined influence on the final product, these are the systems that you want to have full control over as a company. Also, those are the systems that add the biggest value to the company and are the key things a competitor would also need to develop for a rival product. The interesting thing is that while it appears as if the whole automotive world is working on EV tech, not many companies are working on the technologies for very efficient EV’s. This means that we are building up knowledge and Intellectual Property that will be useful and valuable for other parties interested in developing efficient EV’s. This not only provides protection for investors, but also generates new business opportunities for Lightyear — for example, check out our collaboration with DSM on solar technology for other vehicles.

Engineers at Lightyear working on their first prototype of Lightyear One in June, 2019.

The next question is: how far does this go? According to Electrek, Tesla has been improving efficiency by 3% per year. From our World solar Challenge experience, we would get more efficient solar cells every two years: from 22.3% in 2013 to 25.1% in 2019 (about 2% per year). If we extrapolate both trends, we would double the amount of miles you can drive each year on the sun in 15 years, which would make the car energy positive for the average user in most of Europe and the US.

And about that optimisation problem? We will be working with the Eindhoven University of Technology in the NEON project to explore the future of engineering and attempt to create a new abstraction layer for engineering. Instead of having to focus on how to build something, engineers can focus on what to build and, while a computer executes all the mundane (boring! :)) tasks.

Enjoyed reading this founders’ column by Arjo? You can read the first founders’ column by Koen by clicking here.


¹ Per kilometre that is, because of the higher efficiency of electric motors compared to combustion engines.

At the core of Stella’s design was the scoring formula the organisation had published. It gave you one number to optimise towards to maximise your chance of winning. Of course, there were rules to follow, but the cool thing about it was that the design process could be treated as a mathematical 'constrained optimisation' problem.

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