Recent announcements of a ban on UK sales of new petrol and diesel cars from 2035 has stimulated debate on alternatives to fossil fuel for transport applications generally. Battery storage seem an obvious solution for Battery Electric Vehicle (BEV) cars and a driving range of upto 400km seems on the horizon. However battery storage technology alone is limiting for bigger vehicles needing to travel much longer distances. Two factors that work against using battery storage alone are the extra weight added to the vehicle and the recharging time of larger batteries.
Another solution is required for replacing big powerful diesel engines used in transport applications, such as for heavy goods vehicles, trains and shipping. One possible option is the use of hydrogen fuel cells. A hydrogen fuel cell uses hydrogen gas to generate electricity, producing water as a by product. The electricity generated can be used immediately or stored in the vehicle’s batteries for later use. In simple terms a hydrogen fuel cell vehicle can be considered as an electric vehicle with a bigger and lighter storage battery; it still uses electric motors to provide the driving force. Refuelling a hydrogen fuel cell car takes minutes rather than the hours required to recharge storage batteries.
Figure 1 below shows an indicative estimate of the range for different transport applications and how much can be covered by electric storage battery and how much by hydrogen fuel cell. For cars it will be possible to cover the majority of journeys with batteries. For a cross channel ferry or a container ship, that would be cost and weight prohibitive and to achieve the desired power and range an energy carrier like hydrogen would be needed.
The chart illustrates why a key future area for hydrogen fuel cells is likely to be in heavy transport applications. To be a zero carbon form of transport then the hydrogen used would have to be “green hydrogen” produced by the electrolysis of water, rather than produced from fossil fuels.
Transport applications for hydrogen fuel cell technology, are developing rapidly and include.
- The new Toyota Mirai car with 500km range. See Autocar: Toyota Mira Review
- The Aberdeen Hydrogen Bus Project
- The Nikola One Heavy Duty Truck with 750kW power and 1,000km range
- Anglo American developing the world’s largest hydrogen-powered mine haul truck. 900kW power.
- Coradia iLint hydrogen trains used for regional services in Taunus Germany with 1,000km range. See Germany’s RMV places €500m order for 27 fuel cell trains
- Hydrogen fuel cell cruise ship planned for 2023. See World’s first liquid hydrogen fuel cell cruise ship planned for Norway’s fjords
Whilst many of these projects are at demonstrator stage rather than ready for mass market development, it seems likely that in the next few years they will start to become mainstream. By 2025 hydrogen fuel cell technology used in vehicles like the Nikola One heavy duty trucks could well be a financially competitive option for diesel truck operators. Read more at: The Quest For Zero In-Use Carbon & Pollution Emissions From Heavy Goods Vehicles: Part 1
To assist growth in hydrogen fuel cell technology, the development of a hydrogen refuelling infrastructure will be key. This could either be by the use of refuelling stations powered by renewable energy or using a national hydrogen gas grid.