Not everyone can afford a new hybrid, plug-in hybrid or electric car, but those who still wish to drive such a vehicle can still take the conversion route.

Electric car conversions have been around for many years, and many people have converted their regular hybrids to plug-ins too, but a team at Middle Tennessee State University has developed an inexpensive plug-in hybrid kit that could potentially be used on almost any vehicle.

To prove it, MTSU has a technology demonstrator running in a 1994 Honda Accord Wagon.

The kit comprises a battery pack and controller in the trunk, and each rear wheel is equipped with a brushless DC electric motor.

This side-steps the first problem often associated with conversions, which is how to package the electrical components and how to hook up the motors. Each motor in the Honda demonstrator fits around the brake rotor and the wheels can be attached as normal, providing a seamless solution.

The motors--which each develop 200 lbs-ft of torque--then work with the gasoline engine when driving along, reducing load on the engine and resulting in much better fuel efficiency for the same performance.

How much better? Well Dr. Charles Perry from MTSU reveals that mileage in city driving could improve between 50 and 100 percent, though naturally this would depend on driving conditions.

There's no direct connection between the gasoline engine and the motors. Instead, the system operates much like a motorized trolley you'd find in warehouses, where the motors kick in to assist when needed, rather than being constantly powered. As well as being a simple system, the reduced complexity also contributes to a low cost.

That cost is as little as $3,000, according to a statement on MTSU News, and its viability on such a wide range of vehicles means it could become one of the most cost-efficient ways of adoping plug-in hybrid technology.

Conversions can sometimes be hit-and-miss, but Perry says a manufacturing partner has already stepped forward, and the team is approaching companies who might like to adopt the technology to improve the fuel efficiency of their fleets.

That lends the concept some significant clout, so perhaps it isn't too long until you can turn virtually any vehicle into an inexpensive plug-in hybrid...


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