I've had several hybrid cars over the last few years - insurance is always around £600 even with maximum no claims/etc. That's for Jazz hybrid, Auris hybrid and Yaris hybrid.
Apparently Tesla drivers are paying as much as Porsche 911 drivers - with all the tech in new cars, they cost a fortune to repair so this has to be fed into the premiums.
For example if someone bumps the car from behind, as well as a new bumper/etc there is also all teh rear sensors and maybe a battery pack too.
On the Toyota hybrids I had, the part that performs the same thing as an alternator is built into the electric motor - so instead of a few hundred for a new alternator, it's many thousands for repair.