G'day Mate,
No, they are not electric, I would not recommend an electric trainer to anyone. They require specialized skills, to set up & operate, & to charge the batteries, properly.
A glow engined trainer is actually easier to fly than an underpowered electric job, & the flight times are more than trippled. A Boomerang 40 with a 46AX will generally fly for up to 20 minutes, because it is flying at 1/4 to 1/2 throttle most of the flight.
An electric trainer will not fly very well in any sort of wind, unless it has a good sized motor on it, & then you will need larger batteries, & speed controller, to cope with the extra current required by the motor.