Behind the Hybrid Hydrogen project

Thomas Korn was vice president of product management and technology at Aslet Global when the Hybrid Hydrogen Rapid S was being developed

Can you tell us the main difficulties you faced using this system?

The main challenges were combustion control and power loss mitigation. Our focus in the past has been to improve the two, and develop technologies for that. A very challenging aspect was that because it was a new engine, implementing the hydrogen technologies into it in a tight timeframe was also a [big hurdle].

Was there a significant drop in power output when using hydrogen?

If you use hydrogen as a fuel with a lower volumetric energy density, you always lose power. We used two different processes that enabled us to reach 90 per cent of the performance an engine would normally have using gasoline, one of which was using two turbochargers to increase the mixture value in the combustion chamber. Secondly, we used a blend of fuels, which allows us to control combustion and gain more power.

How reliable is the technology?

We think we have shown that even in such demanding and harsh conditions the technology is very reliable. The technology can be implemented relatively quickly in a commercial context.

Finally, what is the top speed of the Hybrid Hydrogen Rapide S?

For the race we were limited to a certain power output by the race organisations. Using gasoline we reached 560 horsepower, and with pure hydrogen we were just below that. We had to use an air restrictor in gasoline mode to bring the engine power down. For the maximum speed, the weight, aerodynamics and the track layout dictate this. We achieved 280 kilometres [174 miles] per hour on the course in gasoline mode and we were not much lower than that [in hydrogen mode].