Truck manufacturers are under pressure to cut emissions.

But which alternative should they turn to? In batteries or fuel cells? Most of the things that consumers buy, be it food, clothing, electronics or anything else, are transported by truck. Hence one could say that these vehicles are the backbone of the trade.

At the same time, however, trucks pollute the environment a lot. According to the European Federation for Transport and Environment in Europe heavy vehicles are responsible for 28% of the transport sector’s gas emissions – despite making up just 2% of vehicles on the road.

These emissions will continue to rise unless truck manufacturers and governments decide to take drastic action.

How will emissions be reduced?

Truck makers can build zero-emissions vehicles using electric motors, which can run in two ways, just like the EV industry: either batteries or hydrogen-consuming fuel cells.

In the case of passenger cars, batteries prevailed due to their lower cost. In trucks, however, the problem is different: such heavy vehicles usually cover longer distances and carry much larger loads.

Just a few years ago producing a battery-powered truck sounded like a joke, says Felipe Rodríguez, director of the heavy vehicle program at the International Council on Clean Transportation (ICCT). “There were a lot of preconceived notions about what a battery could do. How they are too expensive, too heavy, too big”, explains the expert.

The idea was that large trucks would need huge batteries and therefore the load they could carry would be reduced. Still others feared that hauling very heavy loads would drain the truck’s battery too quickly, so drivers would have to stop in the middle of their journey and spend a lot of time recharging it. And all this of course does not sound like a good option for businesses that have tight profit margins.

“However, what has happened in the last few years is shocking,” emphasizes Rodriguez.

Raw materials and components became cheaper and thus the price of lithium-ion batteries plummeted. At the same time, the production capacity of every part of the battery production chain has increased, which is due, among other things, to large-scale investments by governments in electrification.

“An entire automotive industry is helping to reduce the cost of batteries, but only a small industry is working around hydrogen fuel cells,” says David Kempon, professor of mechanical engineering at the University of Cambridge.

Over time, the energy density of batteries has also improved, which means that a truck can now cover a much greater distance with a battery of the same size compared to before. At the same time, the researchers are also working on reducing the recharge time of the batteries – which could be reduced from several hours to just 15 minutes.

What are the advantages of hydrogen fuel cells?

Hydrogen-powered trucks have this big advantage: they can reduce gas emissions without having to reduce their load or require long breaks to recharge.

Fuel cells work like batteries, but instead of consuming electricity, they use hydrogen fuel and oxygen. And their only byproducts are heat and water.

“Refueling a hydrogen-burning truck is more or less the same process as refueling with diesel,” explains Volker Hasenberg, responsible for Daimler Truck’s hydrogen strategy. “You have a refueling station, you store the energy in the truck and all in a few minutes.”

All of this makes fuel cell trucks a particularly attractive option for hauling huge loads, because battery-powered trucks run out of energy much faster relative to their load weight.

Comparing the two technologies

Battery-powered trucks, however, have a head start when it comes to reducing emissions.

According to ICCT these trucks have 65% less emissions compared to diesel trucks, since they use an energy mix of fossil fuels and renewable energy. If, on the other hand, they use “clean” energy, then they have 92% less emissions.

Fuel cell trucks save just 33% of emissions compared to diesel trucks, a figure that rises to 89% when they consume green hydrogen, which is produced with renewable energy. But these trucks are much rarer.

Which technology is cheaper?

Battery-powered trucks have a higher initial cost than hydrogen-burning trucks. But they are very efficient and therefore cheaper to use – and ultimately probably better in terms of cost.

When filling up an all-electric truck, hardly any energy is wasted in the process: the battery is charged at the station and then powers the engine.

In fuel cell trucks, on the other hand, the energy must be converted into hydrogen, transported to refueling stations, and then fed into the fuel cells, where it is converted back into electricity. All of these extra steps result in hydrogen-burning vehicles needing roughly three times the amount of energy compared to battery-powered ones.

What is the future of technologies?

As batteries become increasingly cheaper and more efficient, major truck manufacturers are favoring them over fuel cells.

Some companies, such as Daimler and Volvo, however, are betting that batteries will never “mature” enough as a technology to be used to transport very heavy loads – which is why they are also designing fuel cell trucks.

“We can’t really be sure that one technology will meet the needs of all of our customers,” Hazenberg says. “It is better to stand on both feet than on one.”

However, forecasts dictate that fuel cell trucks will not make up more than 10% of the market by 2050. The vast majority of vehicles will run on batteries.

Edited by: Giorgos Passas