When you’re planning to drive somewhere, it’s important to know if you want the fastest route or one that avoids tolls. Soon there will be another option as well. Google Maps announced that later this year, the app will show users the most eco-friendly driving routes.

“Google Maps will default to the route with the lowest carbon footprint when it has approximately the same ETA as the fastest route,” Dane Glasgow, vice president of product at Google Maps, wrote in a blog post. “In cases where the eco-friendly route could significantly increase your ETA, we’ll let you compare the relative CO2 impact between routes so you can choose.”

The Eco-Friendly Option

The news that Google Maps will default to the route with the lowest carbon emissions really doesn’t come as a surprise. After all, Google, an Alphabet Inc. unit, announced last year that it pledged to have carbon-free operations by 2030 — and would likewise nudge its users to make eco-friendly choices.

Okay, but will users have a choice? The answer is yes. When alternate routes are significantly faster, Google Maps will offer choices and let users decide which route to take. On the other hand, if users always want to see the fastest route, they can do so by adjusting their preferences in the app’s Settings, Glasgow explains.

How Eco-Friendly Routes Are Calculated

About now, you may be wondering how — exactly — Google Maps will determine which route generates the lowest carbon emissions. That’s possible because Google Maps is building a routing model using information from the U.S. Department of Energy’s National Renewable Energy Lab, Glasgow explains. That insight accounts for possible fuel consumption based on a number of factors, such as road incline and traffic congestion.

“What we are seeing, is that for around half of routes, we are able to find an option more eco-friendly with minimal or no time-cost tradeoff,” Russell Dicker, a director of product at Google, told reporters, a Reuters article reports.

Reducing Carbon Emissions

In the U.S., the largest source of carbon emissions is transportation, Elizabeth Irvin, a senior transportation analyst at the Union of Concerned Scientists, says in a CBS News article. That means if carbon emissions are to be lowered in the U.S., drivers’ behavior will have to change — especially the behavior of those who drive most, she said.

“The amount of fuel and greenhouse gas emissions you’ll save is going to really depend on how much driving you’re doing,” Irvin said. “This could be really useful for people doing ride-hailing driving, like Uber, Lyft, or delivery drivers.”

An Added Benefit

An increasing number of cities around the world — especially in Europe — have begun to restrict vehicle emissions. Some have even implemented low-emission zones that ban heavily polluting vehicles such as some diesel cars. Google Maps will also be able to help drivers in those areas.

“To support these efforts, we’re working on alerts to help drivers better understand when they’ll be navigating through one of these zones,” Glasgow wrote. Drivers in those areas will “quickly know if [their] vehicle is allowed in the area,” or if they will need to “choose an alternative mode of transportation or take another route.”

The low emission zone alerts functionality will launch in June for drivers in Germany, the Netherlands, France, Spain, and the UK — on Android and iOS operating systems, Glasgow explains. More countries will be added after that. Interested in road-tripping and sustainable travel? Consider