The fourth-generation Toyota Prius has been spotted testing in prototype form, revealing a shape that worryingly is starting to look a bit like Toyota’s ungainly Mirai fuel cell car.

Looking at this prototype, which was spotted testing in the United States, we can clearly see that the new Prius will sit lower and feature a sleeker profile than the current model. Inside, it looks like Toyota is sticking with the central gauges of previous models, with the most vital information displayed in a screen at the top of the dash. If you look closely, there is a digital representation of the car located here.

Toyota was meant to show its new Prius at the 2015 Detroit Auto Show back in January but delays mean we're not going to see it until later this year or perhaps even in early 2016. The new Prius is currently thought to be launching on the market as a 2016 model.

2016 Toyota Prius spy shots - Image via S. Baldauf/SB-Medien

2016 Toyota Prius spy shots - Image via S. Baldauf/SB-Medien

Part of the reason for the delay is the adoption of a new modular platform known as the Toyota New Global Architecture (TNGA). In designing the platform, Toyota engineers focused on reducing the weight and size of certain components, while at the same time increasing overall body rigidity thanks to higher strength materials and new laser welding techniques.

The new Prius is expected to continue with a nickel-metal-hydride battery pack in a base model, with an optional lithium-ion battery in a more expensive model that may offer better fuel economy. All-wheel drive has long been rumored as another option.

Lighter weight, an improved Hybrid Synergy Drive system and a sleeker shape should all add to improved fuel economy for the new Prius. The current model returns an EPA-rated 50 mpg combined. Somewhere around 60 mpg combined for the 2016 model is likely for the basic hybrid, though a more frugal plug-in hybrid version will be launched once again. We can also expect new versions of the Prius C and Prius V at some point as well.


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