Depends how fast it goes. That 15mph limit is pretty arbitrary, IIRC it would have to be limited to qualify as a bicycle.
15 mph (actually, I think the limit is 25kph) isn't
that arbitary, really. It's pretty representative of the speed an averagely fit utility cyclist would be able to go on the flat (yes, I know many here claim 25mph, but that's not really typical PoB cycling), and is also a reasonable 'finger-in-the-air' guess at a speed at which most accidents would cause minimal injury. It seems quite reasonable to ask for training to be undertaken if you want to travel fast enough to cause cause injury!
The legislation is clear - if power is available above 25kph, it's a moped, not a bicycle. Above 50kph, it's an A1 class motorcycle. End of.
If Nutty's fellow commuter is using a scooter which goes faster than 25kph, and it sounds like he is, then he's breaking the law by riding without a helmet, and presumably without insurance. People periodically have have the book thrown at them for 'misunderstanding' the distinction.
OTOH Zero are making an electric "125" - a proper little fast electric motorbike.
Pah! You want a
Vectrix.
Actually, if my commute was longer,
I'd want a Vectrix!