67 MPG combined, that’s the headline for the 2018 Toyota Mirai, a figure that needs clarification. This isn’t your typical gasoline-powered car; the Mirai is a hydrogen fuel cell vehicle. That impressive MPG figure represents the equivalent fuel economy you’d get from a gasoline car. In reality, the Mirai consumes hydrogen, emitting only water vapor. It’s a zero-emission vehicle, and its “fuel economy” reflects the efficiency of converting hydrogen into electricity to power the vehicle.

City and highway performance

The Mirai’s EPA-estimated fuel economy is remarkably consistent across different driving conditions, achieving 67 MPG in both the city and on the highway. This unusual consistency is due to the nature of the fuel cell powertrain. Unlike gasoline engines, which can experience significant efficiency drops at higher speeds due to increased aerodynamic drag, a fuel cell operates at a more consistent efficiency level. The electric motor driving the wheels provides instant torque, regardless of speed, contributing to linear acceleration and predictable fuel consumption. This even split of economy between city and highway driving makes calculating cost far easier than conventional cars.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2018 Toyota Mirai at $784. This calculation is based on driving 15,000 miles per year, using the national average price of hydrogen fuel at the time of calculation. It’s critical to understand that hydrogen fuel prices can vary significantly depending on location and availability. Also, the Mirai was initially leased with included hydrogen fuel allocation, meaning that the price paid by owners was zero. This subsidized system remains a critical component of Mirai ownership, making it fundamentally different from a typical gasoline vehicle.

Real-world expectations

Expectations about range and “refueling” are especially tricky when considering the Mirai. Published range estimates are around 300 miles on a full tank of hydrogen. In real-world driving, range may vary depending on driving style. Aggressive acceleration and prolonged high-speed driving can reduce the range. This will lead to higher frequency of needing to find a hydrogen station. However, the Mirai is typically leased by California residents living near a hydrogen refueling station. Thus range is not a primary concern.

How it compares

Compared to other alternatively fueled vehicles, the Mirai’s fuel economy shines. The Toyota Prius Prime plug-in hybrid, for instance, achieves 54 MPG combined in hybrid mode after its electric range is depleted. The all-electric Nissan LEAF achieves a combined MPGe of 111. Range and refueling (or recharging) times are key differentiators. The Mirai offers a similar range to many gasoline vehicles and refuels in about 5 minutes, a significant advantage over the hours required to charge an electric vehicle. The Hyundai Nexo, another hydrogen fuel cell vehicle, achieves a slightly higher 61 MPGe combined, reflecting incremental improvements in fuel cell technology. Someone purchasing a Mirai today is looking to experiment with hydrogen power, because cost is not a primary concern.

Tips to maximize efficiency

Gentle acceleration and smooth driving can significantly increase your range. The Mirai’s electric motor delivers instant torque, making it easy to accelerate quickly. However, using that power sparingly will maximize the efficiency of the hydrogen fuel cell.

Plan your routes carefully, especially if you live in an area with limited hydrogen refueling infrastructure. Knowing the locations of hydrogen stations and planning your trips accordingly will prevent range anxiety. Some owners take advantage of their gasoline cars for long highway trips.

Take advantage of the Mirai’s regenerative braking system. This system captures energy during deceleration and braking, using it to recharge the battery. Anticipating stops and coasting whenever possible will maximize the effectiveness of regenerative braking.

Minimize the use of auxiliary systems like air conditioning and heating. These systems draw power from the battery, reducing the overall range. Using these features carefully can help extend the distance you can travel on a single tank of hydrogen.

Keep your tires properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly and inflate them to the recommended level. Consider cross-shopping all Toyota fuel economy data to see if you could get better overall performance from another vehicle. You may even wish to consider the MIRAI MPG across all years to see if you should drive a more modern version.