Toyota has conducted a study that demonstrates the significant reduction in tailpipe CO₂ emissions that can be achieved if more customers use their vehicles' Eco or EV driving modes. The latter mode applies to plug-in hybrids like the RAV4 Prime, which have large enough batteries to sustain brief periods of driving on only electric power.

While such driving modes are usually associated with sluggish throttle response, customers inclined to ignore these more efficient driving modes could be encouraged to use them more often if they knew the benefits.

That's what Toyota aims to achieve with this study, which involved Toyota employees and family members covering over 400,000 miles in Eco or EV mode. Some Lexus vehicles were also used as part of the test, and by comparing data from these cars running in their most efficient modes with vehicles that weren't, Toyota was able to come up with some telling insights.

Collectively, the emission reductions achieved by the study's participants represented $18,304 in fuel cost savings when matched against the national average. 5,091 gallons of gasoline were saved, and Toyota said the reductions in CO₂ were the equivalent of 748 trees sequestering carbon for 10 years. Compared to the baseline, 45,235,623 g of CO₂ greenhouse gases were saved.

Using Eco mode in a non-hybrid model sees the most significant benefits, with a reduction in tailpipe CO₂ of 26%. In a hybrid model, the reduction is 4% since the vehicle already operates more efficiently in general driving.

Remapped throttle inputs in Eco mode and more efficient operation of the HVAC system are the main changes that bring about these reduced emissions.

"We have the ability to use data to help empower consumers so that they can make a difference," said the chief technology officer of Toyota Connected North America, Brian Kursar. "While this study focused on Toyota-owned vehicles, we know there are millions of connected Toyota and Lexus vehicles in the US. If everyone drove in Eco mode, it could help greatly reduce our collective CO₂ output."

While this initiative shows how something as simple as switching to Eco mode can make a difference, many would argue that Toyota needs to do more to combat climate change. The brand was ranked last in a Greenpeace study last year of how the top automakers in the world are working to fight climate change, which is not a great surprise since Toyota still only has one EV for sale in the USA.

That's not to say that Toyota isn't working hard to deliver more efficient vehicles, having introduced a new hybrid powertrain and discontinued the V6 in the latest generation of the Tacoma.