Toyota has announced the official fuel consumption and CO2 emissions figures for the new Plug-In Prius hybrid: 134.5mpg and 49g/km.

Those amazing numbers make the plug-in petrol-electric car the most efficient conventionally engined (ie. not pure electric) vehicle in the UK, by some distance.

It's capable of 15.5 miles on electricity alone, so in theory it need never dip into its tank. Granted, that's unlikely - how many will buy a £30,000 car to drive less than 16 miles a day? But it's nonetheless a huge improvement over the regular Prius, which in real world driving can muster barely a mile.

It takes just an hour and a half to charge the battery from flat using a conventional socket.

All told, the Plug-In Prius boasts a total driving range of 769 miles from one tank. Few Plug-In Prius drivers, if any, will regularly break the 100mpg barrier - the EU fuel economy test has little to do with driving in real life - but even when the battery is drained, Toyota says the car returns 76.4mpg.

There's no sacrifice in space compared to the regular Prius, either: the five-door hatchback still seats five and has a 443-litre boot.

Toyota hasn't revealed exactly how much it will cost when it goes on sale in the summer of this year, but does promise it will be below £30,000 after the Government's £5,000 Plug-In Car Grant is applied. We're guessing an OTR price of around £34,000, then.

The Plug-In Prius will be on display at the Geneva Motor Show, alongside the new FT-Bh small hybrid, which Toyota claims will trounce all its supermini brethren for fuel economy.

So, good times for Toyota salesmen at the moment, what with all this cleanliness and an awesome new, good value sports car.