Now here's a guy that knows how to build a plug-in Prius. I don't mean he just has the technical expertise, which Horacio seems to have in spades, I mean he knows how to build one for only $4000.

I met Horacio at HybridFest. He doesn't consider himself a hypermiler, but he is concerned about the environment and tries to be as ecologically friendly as possible. As a member of the Long Island Prius Owners Group, he and many other members enjoy trading ideas and implementing ways of improving the Prius in one way or another. Thus, adding a heap of batteries, some multimedia extras and a plug in the bumper became a popular idea and was made a reality by Horacio Calvento. Fortunately for him, he is in the retail electronics business, which means he has working relationships with companies like Panasonic, Jayso Electronics and Manzanita Micro (previously seen here). With batteries donated by Panasonic, he instantly saved thousands of dollars. Since he did it himself or with the help of the occasional friend/hobbyist/enthusiast, there were no labor costs involved either except for time. And it only took him a few months. The result is a clean, crisp-looking Prius that gets a cool 88 mpg every day. Imagine what it could do in the hands of a hypermiler.

For those of you not gifted with a friendship with Panasonic, your task is made easier if not less expensive by Horacio's online instructions on the Owners Group website at the Read link. A brief gallery is below, and there are many more in-depth pictures at the aforementioned site.

Coming at you from Hybrid Fest 2007, here's an interview with Ryan Fulcher about his plug-in Prius. Interestingly, Ryan does not consider himself a hypermiler - he doesn't like to worry about his driving habits, and just drives safely. While that may make those of you in the forest green spectrum scoff, the fact that Ryan is a paler shade of green really only makes his Prius' mpg figure more impressive.

He uses a battery charger from Manzanita Micro to not only charge the batteries when plugged in at home, but to have the additional lead-acid batteries charge the stock battery, extending the range of the Prius' electric motor. A simple solution, but unfortunately a costly one. A conversion kit can cost $10-12,000, which would take years to return in fuel savings. However, the point is not to make a business out of this kit. Admirably, it's to show the major automakers that plug-in hybrids are easy to build and that there is a market for them. One would hope they already realize that, but as Ryan says, this "proof of concept" should be pretty good evidence in favor of production.