In India, fuel efficiency is one of the major factors that a buyer takes into consideration before putting down his money on a car. Thus, at Autocar India, we take fuel efficiency very seriously and doing the fuel efficiency runs on the Toyota Prius was very important.
We just couldn’t wait to find out exactly how many kilometres the Prius could stretch a litre to. We never run our cars alone when we test them and the car chosen for reference was none other than our very own Tata Nano. We thought it would be apt to put its low cost, light weight and small engine capacity up against all the technology a global giant like Toyota could throw at it. So how did the two fare?
After multiple runs in the grueling traffic conditions of the city, the average figure for the Toyota Prius was an astonishing 15.1kpl as compared to the Nano’s equally impressive 14.5kpl. That the full-sized Prius outdid the Nano while being heavier and having a larger engine was a revelation.
The reason why Prius delivers better fuel efficiency than the Nano is its 1.8-litre petrol engine that runs on a very high compression ratio of 13:1 and the ‘Atkinson Cycle,’ where inlet valves are kept open longer to reduce pumping losses. It also has an electric motor that acts as a generator which stores energy in the batteries when the brakes are used. The Prius is a parallel hybrid, so it can be driven only on electric power as well as a combination of petrol and electric through a CVT gearbox.
The technology laden Prius has an upper-hand over the Nano as far as fuel efficiency is concerned. But not if you look at the price. For a car that has been critised by the environmentalists, the Nano does superbly, matching the fuel efficiency of the most sainted car, the Prius.