When Toyota's Prius Plug-in Hybrid Vehicle finally makes it to market next year it will come with two new features that weren't on the prototype we first drove last October. The first of the tech additions will be a driver-selectable EV mode, while the second will be a full regenerative braking system. Allow us to explain.
First up is the selectable EV mode, meaning that the driver will be able to choose when they want to use the estimated 10 miles or so of electric-only range. While other systems use the EV range immediately and then switch to a type of hybrid mode, the Prius PHEV would allow owners to get out on the highway in a normal hybrid mode and then switch to EV mode once they got close to the city where the traffic congestion is worse.
Second is the ability to full recapture electric energy under braking. In the prototype model we tested the regenerative brakes could only be used to sustain the hybrid drive system once the EV mode had depleted. The new version will, however, allow for continued (and possible full, but extremely unlikely) regeneration without having to plug it in. This could significantly expand the distance you're able to travel in EV mode depending on the terrain like if you're daily drive includes a long downhill run.
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Prius PHEV to Gain Driver-Selectable EV Only Mode, Full Regenerative Braking on AutoGuide.com