Plug-in hybrid cars. There’s something about them, isn’t there? Is it an image problem? They may not belch out as many nasties as your average car, but they do tend to ferry around worthy celebs and the smugs residing in the country’s better post code areas. Greenbang thinks of hybrids, she thinks of Leonardo di Caprio and queasiness isn’t far behind.

Whatever the problem, the boffins at the Motor Industry Research Association (MIRA) have come up with an ingenious piece of technology that sidesteps all of that, with a bit of tech that can turn the average motor into an emissions saint.

The MIRA has unveiled a retrofit ‘hybrid conversion system’, which can be installed in your beloved petrol-beholden car and make it that bit more eco-friendly.

The 50/50 hybrid system uses two 35 KW motors to power the rear wheels, while the petrol fueled engine drives the front. The electric motors are powered by a removable battery pack that can be charged by the engine or plugged into your home’s mains.

MIRA reckons it can cut fuel costs by 61 percent and emissions by 39 percent but won’t have any impact on top speed or acceleration. MIRA insists, though, that its real benefit over purpose built hybrids is that you can bring the battery into your house and recharge it there, rather than having to run an extension lead out to your car.

But don’t go rushing to your nearest garage to pick up a system just yet. The system is only at prototype stage, and MIRA hasn’t released details yet on its potential cost or on a release date.

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