Toyota has launched the second-generation Sora, a hydrogen-powered fuel cell bus for public transport. Built in collaboration with Isuzu, it promises more range thanks to improved efficiency. But will it be able to convince European customers?

While zero-emission buses in Europe are mostly battery-electric, hydrogen-powered fuel cell solutions can be seen as a viable alternative in some parts of the world. Toyota Motor Corporation is one of the companies betting big on a hydrogen society, including with buses.

Toyota launched the first generation of its Sora hydrogen-powered public transport bus in 2018. Now, eight years later, it is time for a completely new generation. The new Sora is 10.55 meters long and seats 70 passengers, including the driver. The completely flat floor can also easily accommodate wheelchair users.

Improved efficiency

While the first-generation Sora was a fully Toyota-developed model, the new one is built in collaboration with Isuzu. In fact, Toyota uses Isuzu’s full-flat BEV route bus platform, putting the fuel cell and hydrogen tanks on the roof.

The three hydrogen tanks have a total capacity of 471 liters and carry hydrogen at 700 bar (about 19 kg). The polymer electrolyte membrane fuel cell stack can deliver up to 113 kW to a Li-ion battery pack, which powers the two 110 kW traction motors.

The new generation has greatly improved efficiency. While the first-generation Toyota Sora with a 228 kW fuel cell stack and a NiMH battery could manage 200 km on a 600-liter tank, the new generation offers 300 km on a 471-liter tank. This equates to 50% more range on a 20% smaller tank capacity.

The tanks support future high-flow filling, meaning they can be filled in 10 minutes. This gives them an advantage over battery-electric buses, which have longer charging times and reduced uptime.

A viable solution for Europe?

In many respects, the second-generation Toyota Sora looks like a big improvement. But is it a solution for Europe? In Belgium, the limited hydrogen infrastructure makes it unlikely that a large fleet of buses can run on hydrogen. Battery-electric seems the way forward for zero-emission buses.

In some other European countries, hydrogen buses could be an addition for certain uses. But while Toyota’s new-generation Sora is greatly improved over the previous one, it doesn’t really bring much new to the European market. Existing hydrogen buses like the Solaris Urbino and Wrightbus GB Kite Hydroliner offer a similar range and/or refueling times.

But the biggest competitor for the Sora in Europe could be the Caetano H2. City Gold, which uses… a Toyota fuel cell stack delivering 70 kW.

Caetano combines the stack with a 100 kWh LFP battery, which the lower-power-output fuel cell recharges at its optimum efficiency and can also be recharged externally—the Caetano H2.City Gold promises a 600 km range, doubling the Sora’s range.

Limitations

Moreover, a technical issue might make the Sora less appealing in the European market. Toyota chose 700-bar tanks, a pressure customary for cars and light vehicles, which have limited space for larger ones. But a 700-bar system is more expensive than a 350-bar system, which is generally used for heavy applications.

And although Hyundai, Toyota, and, in the future, also BMW (using a Toyota Fuel cell stack) are betting on hydrogen cars, hydrogen fueling infrastructure seems to be shifting more toward 350 bar.

Filling up a 700-bar system at a 350-bar station doesn’t mean the fueling time doubles. It means the tanks can only be filled to 350 bar, halving the vehicle’s range.

Moreover, hydrogen can come with significant energy losses during production. But that depends on the production method. Using electricity directly from a battery is more efficient, although battery production is more energy- and material-intensive than fuel cells.

And then there is the price of fuel cell buses. In the Japanese market, the Sora costs around € 500,000, but the European price could be much higher. In general, hydrogen buses are more expensive than battery-electric buses. This limits their appeal and could limit their viability to a small number of applications.