As most electric car fans will tell you, it’s much easier for automakers to build an all-electric car from scratch than it is to repurpose an existing gasoline model with an electric drivetrain.
In the case of Toyota’s RAV4EV however, the Japanese automaker, with help from Californian luxury electric car company Tesla Motors, has turned its RAV4 crossover SUV into a limited-run all-electric model.
While Tesla handled the all-electric drivetrain, Toyota’s team tackled making the car go further, by reducing the drag coefficient of the popular SUV from 0.31 to 0.30.
The lower the coefficient of drag, the more easily a car moves through the air, resulting in a higher energy efficiency and ultimately, longer range.
Without changing the physical dimensions of the RAV4, as Toyota explains in its recent YouTube video, Toyota engineers had to go to extreme lengths to make the SUV more slippery.
First, it examined its global production of gasoline RAV4s, sourcing the most aerodynamic wheel and tire combinations, as well as the most aerodynamic external trim and headlight combinations.
Then it redesigned large parts of the RAV4’s body panels, including crafting a new grille, mirrors, and rear spoiler.
Underneath,Toyota had to completely reengineer the car’s belly, replacing the usual gas tank, exhaust and transmission system with the smooth underside of the RAV4 EV’s Tesla-sourced lithium-ion battery pack.
“The changes that we’ve made to this vehicle is the equivalent to removing a football player training parachute from the back of the car.” said Aerodynamics Development Engineer Stefan Young. “That’s not hard if you’re running 40 yards, but if you’re driving this thing 150 miles, that’s a significant drag on the back.”
As we’ve discovered in the past, having a roof rack on your electric car significantly reduces its range, which is why Toyota decided to remove the roof rack options found on the gasoline RAV4 when building the RAV4 EV.
“As a big cyclist, I apologize for the roof rack. But as an aerodynamicist, I say put your bikes in the back,” Young joked. “By removing the roof rack, we reduced the frontal area and we reduced the drag a little bit.”
The result is a lighter, more efficient car that goes further per charge.
After driving the car, and seeing the lengths to which Toyota went to improve aerodynamics and range on the RAV4 EV, we remain impressed by this all-electric crossover SUV.
There’s only one problem. As far as we know, it’s still a compliance car, built to satisfy California regulations for zero-emission vehicles, which means only a limited number of cars will be made, and very few consumers will be lucky enough to get their hands on one.
Let’s hope Toyota changes its mind.
2012 Toyota RAV4 EV, Newport Beach, California, July 2012Enlarge Photo