Toyota is adding two new models to the Prius – a plug-in hybrid version of the current hatchback and a seven seat MPV.

The first plug-in hybrid was supplied to its celebrity owner earlier this week – His Serene Highness, Prince Albert II of Monaco (it's a good job our own Prince Philip doesn't go by that title, don't you think?). The headline figures are spectacular: 49 g/km of CO2 and 134.5 mpg, with a battery range of 15.5 miles. However, potential buyers should be warned that those figures are the result of the vagaries of the EU test cycle. Unless you can recharge the car from the mains every 30 miles, your fuel consumption and CO2 figures are likely to be around half the official ones. The price is £27,895.

The other model is the Prius + compact MPV. This is a Prius with a new bodyshell, but similar mechanicals to the familiar Prius. We say "similar" because the batteries have been moved from the boot to behind the dashboard in order to make space for three rows of seats.

As well as the hybrid drivetrain, the Prius+ has two other clever innovations. The big panoramic roof is not made from glass, but resin, which cuts the weight of the panel by 40%. Finally, the hybrid drivetrain is used to smooth out the ride. The idea is that, if the front of the car lifts over a bump, power is instantly reduced slightly to bring the front down and, conversely, slightly more power is applied if the front dips. Toyota says it makes a noticeable difference to ride comfort. Prices start at £26,195.