Conversion kits are already available to turn a Toyota Prius into a plug-in. It's expensive, but Consumer Reports wanted to test to see what the future's going to bring.
Now you can have a lithium-ion battery installed in your Prius, plug it in at night, and get even better gas mileage.
The batteries are like a really big laptop battery. They're put in the wheel well where your spare tire normally goes. And a small hole has to be made for the plug.
The Prius then can go longer distances and at higher speeds solely on battery power.
Tests found the plug-in Prius did not routinely get 100 miles-per-gallon as claimed, but still, the plug-in kits really boosted mileage.
"The plug-in Prius got 67 miles per gallon overall during the first 35 miles, compared with 42 miles per gallon overall the Prius normally gets," said Consumer Reports Jon Linkov.
But don't reach for your tool kit just yet.
"You can't do this installation yourself and there are only a handful of locations that are authorized to do the conversion." said Linkov. "We had to wait five months to get our kit installed."
And then there's the matter of the money. Converting the Prius to a plug-in cost more than $10,000.
"From a dollars-and-cents perspective, doing this conversion makes no sense because it would take decades to recoup the cost. But the plug-in technology is a viable option if it becomes massed produced and costs come down." said Linkov.
The plug-in Prius Consumer Reports tested ran 35 miles before the battery ran down.
When you consider a majority of Americans drive less than 40 miles a day, a plug-in car could dramatically cut fuel consumption.
Besides the Prius, Several other plug ins are planned, including the Chevrolet Volt.