Here is another potential hybrid aircraft, the DA36 E-Star aircraft, that promises to reduce carbon emissions by 25%. The aircraft it essentially similar to electric vehicles we see today like the Toyota Prius and the Chevy Volt. It also has a gas-powered engine to go with its battery.
The battery powers the motor while the gas engine is exclusively for battery charging. However due to limitations on the battery power capability, there are weight limit constraints. The battery was actually just meant to help power up the aircraft prior to taking off.
This should be a positive outlook although hybrid aircrafts have yet to take off from alternative power sources like land-based vehicles have.