Toyota Hybrids Drive Over 60% of the Time in Zero Emissions Mode

University College Dublin Study Reveals Toyota Hybrids Drive Over 60% of the Time in Zero Emissions Mode
A new study carried out by University College Dublin (UCD) academics,has revealed that in typical Irish commuting conditions, Toyota’s hybrid powertrain system drives in zero emissions mode (ZEV) for significantly more than half (62%) of the time and over 40% of the distance covered.

Toyota Hybrid Study

Zero emissions mode describes the time the internal combustion engine is not running and the vehicle is therefore emitting no pollutants. The longer the car is in ZEV mode the more significant the air quality benefits for other road users.

The study tracked seven drivers who commuted to UCD, Belfield from Drogheda, Wicklow, Aughrim, Smithfield, Blackrock and Dundrum (2), over a full week each during last November, combined with normal additional family driving. Conclusions are based on the analysis of the more than 2,000 kilometres of driving across motorways, rural roads and city driving that resulted.

The routes reflect typical Irish commuting conditions. The researchers measured the time the cars spent in zero emissions mode versus internal combustion mode. No restrictions or driving guidelines were given to the drivers.


The study sampled a number of journeys that reflect typical urban, outer suburban and provincial driving conditions in Ireland.

It showed that for the journey from Smithfield to UCD, the self-charging hybrid was in zero emissions mode on average three-quarters (76%) of the time and for over half (57%) of the distance, while drivers from Dundrum and Blackrock were in zero emissions for two-thirds (64-67%) of the time of their journey.

Meanwhile, the commuters from Drogheda, Aughrim and Wicklow town to UCD spent over half (56%) of their time in zero emissions mode over the respective 644 km, 452 Km and 293 Km driven over the course of the week’s testing.

The study also revealed that, on average, fuel consumption for the Prius was 4.92 litres per 100 kilometres (57 mpg) and average C02 emissions were 114.2 grammes per kilometre. The three drivers with the longest commutes had the best fuel economy, averaging almost 60 mpg, a fact that clearly demonstrates the merits of hybrid cars for long distance driving.


Environmental Impacts

Self-charging hybrids have a significant role to play in decarbonising the car fleet and in delivering electrified driving to the Irish consumer. It’s clear that hybrids deliver societal benefits for both rural and urban drivers. These cars do not need additional infrastructure or behavioural change from drivers. In a country with over 2 million cars with combustion engines, there are clear and tangible benefits from self-charging hybrids that drive 60% of the time in zero emissions mode.


The study conclusively shows that our self-charging hybrids are in zero emissions mode for well over half of their journeys, including on long drives. It underlines the fuel economy and positive environmental impact that self-charging hybrids can bring to society with reduced C02 and improved air quality, which, in turn, can deliver significant health benefits for cyclists and pedestrians traveling the same routes