Cigarette Racing’s unveiling yesterday of its AMG Electric Drive 38’ Top Gun raised a lot of questions. After all, it’s not every day you see a battery-powered go-fast boat that would cost—if it were for sale right now—more than $5 million. So to answer all of those questions, I sat down with Peter Kagi from AMG in Germany. Kagi was one of the primary engineers on the project.
So how did this project come about?
Well, as you know, there is a relationship between Cigarette and AMG, and we are a corporation that always tries to showcase new technologies. Last spring, there was an idea to create an electric powerboat and because of the link AMG has with E-Drive (the SLS AMG Coupé Electric Drive) cars there was a link.
How does the E-Drive system work?
The easiest way to explain it is to start with the car. On the car, we have one electric engine connected to each wheel. The development of this drive was very difficult, because at Mercedes everything has to be very good, very safe, and every system has to have redundancy. Every system is done more than two times.
Why not one larger electric engine instead of four smaller ones?
There is no space for a drive train. All the space is occupied by batteries.
Are those the same electric engines you used in the boat?
Yes, but there are 12 engines because for the boat four is not enough. They are set up in a double-star arrangement. Each engine propeller is fed by six engines. Each engine weighs 50 kilos and there are two gear boxes (before the Mercury Racing M8 drives). So it’s a very light drive system.
But there are more than two tons of Lithium batteries, from HPP, the best batteries on the market and the same batteries that are used in the car. The are 3,400 cells with inverters, and it all is controlled by a CPU fed through a BUS system.
Is it AC or DC electric power?
(Laughs) It is actually a hybrid of both.
And of course the batteries are rechargeable.
How long can the boat run with fully charged batteries?
Battery life depends on how you throttle, but we estimate it this way: You have 15 minutes of idle speed, a half hour at 70 mph, a couple of blasts to 100 mph and another 15 minutes of idling. And you still will have a good reserve of electricity. In a boat you have instruments and lights, and you don’t have a generator so everything comes from the batteries. To start the system we actually have another battery, a small Lithium battery.
Did the marine environment force you to provide extra protection for all those batteries?
Water is no problem. The battery is completed sealed. It is the same battery we use in the car, so it has to be very safe. For example, in the event of a crash it has to stop immediately.
Is the ultimate limit to this project and running time have to do with battery technology?
Yes, but just look five years back. Five years ago, if you said AMG is building an electric sports car people would have laughed. But now we have it. I think we will see many things in this field.
It’s quite a project.
This is a boat you see first and then hear. With combustion power, you hear the boat first. Then you see it.