There are two main concerns in order to power an aircraft long range with electricity, the battery is too heavy and running out of power during flights is almost difficult.
The company will start testing its electric aircraft with four passengers called GT4. In fact this will be a hybrid aircraft with a 1.5-liter single gasoline backup engine in addition to its powerful batteries. A 200mile flight with this hybrid aircraft is estimated to consume electricity of about $20 instead of the same distance with a normal engine which consumes no less than $80 of gasoline.
The hybrid powertrain consist of batteries to help it take off, climb and cruise to a range of 300 miles after which the battery controller triggers mechanism that starts the gas engine and the batteries are recharged.
This hybrid aircraft has a design with three wings which provides enough space for batteries and a carbon composite propeller durable enough to endure the torque produced by electric motors. GT4 has a combination of two smaller electric motors that generate 600hp and is capable to sustain about 400hp during flight. The electric motors are powered by a 900 pound lithium-ion battery array with 236 individual cells.
Even the powertrain is lighter than conventional gas engine and allows the possibility to put extra batteries to balance the gravity center of GT4. Maybe in the future the gas engine will be replaced with much lighter batteries and GT4 will be only electric one.