When calculating travel directions, standard navigation apps historically prioritised only one variable: speed. The fastest route, however, is not always the most economical or environmentally sustainable. Driving at high sustained speeds on motorways or idling through stop-start city congestion consumes fuel and battery power in dramatically different ways depending on your vehicle’s powertrain.
To help motorists reduce fuel bills and cut carbon emissions, Google Maps includes built-in Eco-friendly routing paired with Engine Type Selection. By informing Google Maps whether your vehicle runs on petrol, diesel, a hybrid powertrain, or fully electric battery power, the navigation engine tailors route calculations specifically to your vehicle’s mechanical efficiency profile. In this guide, we explore how to set your engine type in Google Maps on Android and iPhone, and how eco-friendly routing works behind the scenes.
How Engine Type Influences Route Calculation
Different automotive powertrains achieve maximum efficiency under very different driving conditions:
- Petrol (Gasoline): Internal combustion petrol engines run most efficiently at steady speeds on smooth, flat roads, but waste significant energy in stop-and-go urban traffic.
- Diesel: Diesel engines excel at higher speeds on long motorway stretches, where their thermal efficiency and torque allow sustained low-RPM cruising over extended distances.
- Hybrid: Hybrid vehicles shine in suburban traffic and variable-speed roads where regenerative braking recharges the auxiliary battery pack during deceleration.
- Electric (EV): Electric vehicles consume disproportionately higher battery charge at sustained high motorway speeds due to aerodynamic drag, but maintain exceptional efficiency at moderate rural and urban road speeds.
When an engine type is specified, Google Maps compares real-time traffic data, elevation gradients, constant speeds, and typical junction delays to suggest routes that consume the lowest net energy—often saving considerable fuel with only an unnoticeable difference in travel time.
How to Choose Your Vehicle Engine Type in Google Maps
You can set or update your vehicle powertrain directly inside the Google Maps mobile app on iOS and Android:
- Open the Google Maps app on your smartphone.
- Tap your Profile picture or initials located in the upper-right corner of the search bar.
- Select Settings from the menu.
- Scroll down and tap Navigation settings (on iOS, tap Navigation).
- Scroll to the Route options section.
- Ensure that the toggle next to Prefer fuel-efficient routes is turned on.
- Tap Engine type.
- Choose your vehicle’s powertrain from the list:
- Petrol
- Diesel
- Hybrid
- Electric
- Tap Done or navigate back to the main map screen.
How to Change Engine Type While Planning a Trip
If you regularly borrow another car, rent vehicles while travelling, or drive multiple family cars, you can quickly adjust the engine type directly from the directions preview screen without opening general settings:
- Search for your destination in Google Maps and tap Directions.
- Tap the three-dots menu icon in the top-right corner next to the starting location and destination fields.
- Select Route options from the dropdown menu.
- Under Engine type, select the appropriate powertrain for the car you are currently driving.
- Tap Apply. Google Maps will instantly recalculate available routes, marking the most fuel-efficient choice with a green leaf icon.
Understanding the Green Leaf Icon and Fuel Savings
When eco-friendly routing is enabled, Google Maps displays a small green leaf icon next to the route that offers the lowest estimated fuel or energy consumption:
- Equal Travel Time: If the fuel-efficient route has roughly the same estimated time of arrival (ETA) as the fastest route, Google Maps will select it as the default choice automatically.
- Route Comparisons: In cases where the eco-friendly route takes slightly longer, Google Maps displays the estimated percentage of fuel savings alongside the time difference (e.g. “8% less fuel, +3 min”), giving you complete control over whether to save money or arrive minutes earlier.
Overriding Fuel-Efficient Routes When Speed Is Critical
If you are running late and want Google Maps to consistently prioritise the absolute fastest arrival time regardless of fuel economy, you can disable eco-friendly routing entirely:
- Navigate to Google Maps > Settings > Navigation settings.
- Under Route options, toggle off Prefer fuel-efficient routes.
- Google Maps will now default purely to the lowest transit duration on all future journeys.