SPY PICS: New Toyota Prius draws near

A fresh batch of spy shots showing Toyota's fourth-generation Prius in testing appear to confirm the legitimacy of apparently official promotional images leaked across the internet yesterday.

The Mk4 Prius, which is expected to debut at the Tokyo motor show in late October before going on sale in Australia early next year, was spotted as long ago as early 2013, when Toyota confirmed it will be lighter, more efficient and cheaper to build.

Development of the successor for the world's top-selling hybrid – the third generation of which went on sale here in 2009 but has found just 252 Australian homes so far in 2015 – was reportedly delayed by six months following the switch to Toyota's new billion-dollar Toyota New Global Architecture (TNGA) platform.

The 2016 Prius will be first to ride on the lighter new platform, which Toyota says is 35 to 60 per cent stronger than the existing hatchback's underpinnings and has a lower centre of gravity, improving handling dynamics and contributing to a lower, wider and sportier look for the new model.

These new images of the car on the road in southern California show a sleeker silhouette led by a lower, sloping bonnet that's almost as steep as the A-pillars, and a pointier nose with a prominent Toyota emblem and LED headlights – just like the car in this week's leaked images. Also contributing to the Mk4 Prius' wedge-shape profile is a rising beltline with concave shoulders.

However, according to the Taiwanese website that leaked the official images, Autonet, the new Prius will measure 4550mm long, 1770mm high and 1490mm wide – making it the same width as the current car, but longer (+70mm) and taller (+25mm).

The car spied here is the standard Prius hybrid, but the other car seen in the leaked images is believed to be the new Prius Plug-In Hybrid , which replaces the model not sold here, brings more design differences and will join the standard Prius in Japanese, US and European showrooms soon after.

No official technical information has been released, by Toyota, but according to the document uncovered by Autonet, the new car will be more than 100kg lighter at 1280kg, despite its larger dimensions.

Toyota has previously indicated its third-generation petrol-electric powertrain will make the new Prius at least 10 per cent more efficient, but according to Autonet it will sip as little as 2.5L/100km – more than 1.0L/100km less than the current model, which consumes 3.9L/100km on the ADR Combined cycle.

The plug-in hybrid version, meantime, is said to average just 1.4L/100km, while being able to cover up to 50km on electric power alone.

Apart from less weight and improved aero, key to the new model's increased efficiency is a more frugal 75kW 1.8-litre four-cylinder petrol engine, which combines with an electric motor to output a total of at least 150hp (110kW) – up from 100kW currently.

At this stage it's unclear whether the Prius will continue with a nickel metal hydride battery pack, or a more advanced lithium-ion battery.

Toyota has promised the larger new Prius cabin will offer improvements in "design, layout and ease of operation", but it has also suggested the Mk4 will be cheaper than the MkIII, which is priced from $32,490 in Australia, because its new chassis architecture is claimed to make future Toyota hybrids up to 40 per cent cheaper to develop, and only 75 per cent of the savings will be reinvested.

Toyota has sold more than five million Prius vehicles since 1997.