My company has just secured a patent for an Energy Cell Regenerative System For Electrically Powered Aircraft (May 9, 2017). A properly designed and efficient regen system can flip the prohibitive physics enough for a net gain and be a worthwhile addition to an electric aircraft. A key is to design a lower pressure area beneath a cowling venturi and harness some of the prop blast in flight  (there is some)...it tornadoes around the fuselage but beneath the cowling is,combined with the speed of the aircraft, a source of kinetic energy. The turbine is a centrifugal design and is tucked away under a blister which makes the system nearly drag free when not in use. The PMA can produce 3kw and weighs 19 pounds. The whole system weighs 31 pounds and includes a mosfete controller and a buck boost inverter similar in design to those found on Toyota's Prius. There is a lightweight Maxwell super capacitor module as a "charger". Power generated from the system charges a probably lithium battery pack that has been designed to be charged and discharged simultaneously (see the patent), through an algorithm managed by the controller. The lighter we can produce the system and also speed up charging by reducing the battery's internal resistance the more efficient, and practical, it will be. We haven't been permitted to flight test it, but calculations derived from a Cessna 152 mule indicate good potential for regen. It can be used as a rescue system, during descent, or when practical to adjust prop pitch. Knee jerk reaction from laymen and engineers has been negative until they carefully study the invention, then consensus seems to be ..."That should definitely be developed further". Patent is on the market. Patent #US 9,643,729 B2 more info www.electronair.com

My company has just secured a patent for an Energy Cell Regenerative System For Electrically Powered Aircraft (May 9, 2017). 

A properly designed and efficient regen system can flip the prohibitive physics enough for a net gain and be a worthwhile addition to an electric aircraft. A key is to design a lower pressure area beneath a cowling venturi and harness some of the prop blast in flight (there is some) it tornadoes around the fuselage but beneath the cowling is,combined with the speed of the aircraft, a source of kinetic energy. 

The turbine is a centrifugal design and is tucked away under a blister which makes the system nearly drag free when not in use. The PMA can produce 3kw and weighs 19 pounds. The whole system weighs 31 pounds and includes a mosfet controller and a buck boost inverter similar in design to those found on Toyota's Prius. There is a lightweight Maxwell super capacitor module as a "charger". Power generated from the system charges a probably lithium battery pack that has been designed to be charged and discharged simultaneously (see the patent), through an algorithm managed by the controller. The lighter we can produce the system and also speed up charging by reducing the battery's internal resistance the more efficient, and practical, it will be.

We haven't been permitted to flight test it, but calculations derived from a Cessna 152 mule indicate good potential for regen. It can be used as a rescue system, during descent, or when practical to adjust prop pitch. Knee jerk reaction from laymen and engineers has been negative until they carefully study the invention, then consensus seems to be "That should definitely be developed further". Patent is on the market. Patent #US 9,643,729 B2