100 MPG Plug-In Prius: Pat’s Garage

One hundred miles per gallon (MPG) might seem like a far fetched dream to most folks. But to those on the cutting edge, it’s a reality. With a conversion kit, a half a day of work, and a pocket full of cash, a second-generation Toyota Prius can be quickly and seamlessly converted to a 100 MPG plug-in hybrid. Camera gear in hand, we stopped by the the A123 Systems/Hymotion booth, on the Plug-In 2008 conference show floor, where Pat Cadam (of Pat’s Garage and greengears.net) shared how simple it is to achieve 100 MPG.

Situated in San Francisco, Pat’s Garage is at the top of the short list of the country’s leading plug-in hybrid conversion shops, as it stands on both the front line and the epicenter of the plug-in revolution. Pat’s mechanics have completed hundreds of plug-in conversions to date and expect to perform thousands more in the future, as the technology matures and the word gets out.

Double your mileage in a day? As hard to believe as it might seem, you can drop off your stock Toyota Prius in the morning, and drive home that evening with a cutting edge 100 MPG plug-in.

The process of converting a standard issue Prius to plug-in technology is a straightforward procedure. The spare tire is removed to make space for the Hymotion box (containing the Lithium phospate batteries, smart battery charger, battery management system and computer) before the new high voltage wiring is run. The Hymotion box is installed, along with a charging outlet on the rear bumper. Everything gets buttoned up and after half a day of real-world road testing to cycle the batteries, the modded Prius is ready for delivery.

It’s important to note that the Hymotion conversion kit has gone through government crash and emissions testing and is certified. There’s no bailing wire or bubble gum. As Pat explains, “this is a well-tested, safe product.”


– by

3 thoughts on “100 MPG Plug-In Prius: Pat’s Garage”

  1. Why Pat’s Garage can make this happen and not Toyota is a mystery to me. I’ve seen the process and the price to convert and if there isn’t a stock plug-in hybrid available by the time I am ready to buy a new car in 2 years, I am so going the Prius – conversion kit route. Thanks for letting people know about this.

  2. Since the price of batteries have dropped. I hope your prices have dropped for these upgrades. Think of the economy of scale.

  3. I currently own a 2007 Prius. In researching the cost of the Hymotion conversion kit at $11,408 total cost installed out the door might be a bit of a streach cost wise since I already get 50+ mpg.

Leave a Comment