[amorphous]

Seems like this EESD would work for you. Not sure when/if it will be marketed, but in a later video, the scooter shown went over 100 km.

There may already be a pedal assisted bike available with the range you need, if not, couldn't you get a extra battery, leave it to charge at some location in town? Perhaps a service station or garage might be willing to work with you on something like that for a nominal fee?

You could then just swap out batteries for the trip back.

[amorphous]

Something that might work for ya: http://www.prodecotech.com/phantom-400m-stride-400m

This eBike’s range is 25 -35 miles per charge.