The benefits of ebike are numerous.  Most people rule out traveling to work by bike, but with an electric bike longer journeys become a pleasure.

When on the flat you can turn off the electric motor and peddle as if you were on a normal bike, but when the gradient get a little steeper use the motor to iron out those hills, you will be surprised how easy a commute becomes and yes you will help lower your carbon footprint.  

Because ebike are easier to use in hilly areas, in strong winds or when carrying heavy loads you will tend to use it more than a traditional bike, and yes you will become fitter.