The seemingly impossible car
Arjo van der Ham — Co-Founder
Technology today is evolving faster than ever. When you stop and think about it, the possibilities seem endless. Every day, a lot of great (or to be honest, most of the time not-so-great) ideas pop into my, our, or your head. Although the seemingly impossible ideas are hard to achieve, it does not have to imply that they are bad ideas. That’s why at Lightyear we like to do some quick back-of-the-envelope calculations to check the feasibility of some of those ideas.
Before we founded Lightyear, we used to meet every Thursday evening to do just that. After concluding that we wanted to start a business to make this world a better place by combating climate change, we started looking for the best solution. The first step we took was to investigate the underlying causes of human induced climate change, and we quickly found the following graph:
We were shocked by the red part, that shows that 22% of the Dutch emissions are from bunker fuels for ships. Hence we started to do some calculations to see if we could electrify some of these oil-burning ships!
As an example, we took the Maersk Triple E class (one of the biggest container ships in the world). The longest trips for these kinds of ships take 30 days. They run for 30 days at the rated power of 60 MW, with an electric powertrain efficiency of 90 %. This would require 48.000 MWh (~½ million Tesla Model S batteries) of energy to be stored in the batteries. At an energy density of 570 Wh/L (2015), the batteries would take up 2190 TEU, or roughly 12 % of the volume of the ship.
So far so good, we thought. But what do the containers themselves weigh? And what do the batteries weigh? It turned out that at 210 Wh/kg one TEU of batteries would weigh roughly 100 tons. In contrast, an average loaded 20-foot container only weighs 14 tons. And hence the total battery would weigh 90% of the total load capacity of the boat…
And then we have not even started about charging our heavyweight lithium-bomb. It takes roughly 34 hours to unload and reload the ships, which means we would have to charge the ship with a power of approximately 1500 megawatts, also known as the largest coal-fired power plant in the Netherlands (Eemshaven Centrale).
A brand new coal-powered plant in Eemshaven, The Netherlands
So based on these assumptions and rough calculations we ASSUMED electrifying ships to reduce the bunker fuel emissions was a shitty idea.
In the autumn of this year, the battery-powered ships will be navigating the Dutch waterways. I realize now that we made all the wrong assumptions when we killed the idea 3 years ago:
- Ships for inland waters can charge every day instead of every thirty days
- Using containers for the batteries makes them hot-swappable. This means you can slow-charge them on the shore (and maybe use them for grid stabilization at the same time?)
The 1.28 horsepower solar car
An idea isn’t necessarily bad when it (battery electric ships) does not work for a certain use-case (intercontinental shipping). Our biggest error was not realizing this. Sometimes you have to think outside the box!
Anyway. On the same day I read the article about battery-powered ships, Futurism wrote an article about Lightyear. In this item, they referred to another article from last year by an engineer who concluded that solar powered cars would not work, since they would only have 1.28 horsepower available. Yet, he made one big assumption about the way solar power is harnessed, because you do not use the power from the solar cells directly. The power is stored in a battery and then used while driving. Questions like these pop up: How long do you drive your car, and how long is the sun shining every day?
With thriving minds and a genius engineering team, we will provide you a car that can drive up to 10.000 kilometers per year on the power of the Dutch sun.
If you want to read more into the way the solar car works, check out this blog post!