The urgency of the climate crisis means that the world should focus on accelerating the build-out of battery-powered vehicles and fast-charging infrastructure, rather than hydrogen fuel-cell cars and trucks and H2 filling stations, according to a study in the journal Nature Electronics.
“Hydrogen will play a vital role in industry, shipping and synthetic aviation fuels. But for road transport, we cannot, I believe, wait for hydrogen technology to catch up, and our focus now should be on battery electric vehicles in both passenger and freight transport,” writes Dr Patrick Plötz, co-ordinator of the energy economy business unit at the Fraunhofer Institute for Systems and Innovation Research (ISI) in Germany.
Cars
As far as Plötz is concerned, “the window of opportunity to establish a relevant market share for hydrogen cars is as good as closed”.
He points out that at the beginning of last year, there were about 25,000 hydrogen fuel-cell cars on the road, two FCEV models available to purchase (Toyota Mirai and Hyundai Nexo), and about 540 hydrogen filling station in operation around the world.
“In contrast, by the beginning of 2022, there are likely to be about 15 million battery electric and plug-in hybrid vehicles on the road across the world. Almost all manufacturers now sell such vehicles, with more than 350 models available globally,” Plötz says
And while most battery electric vehicle (BEV) drivers currently charge at home, there were about 1.3 million public charging points in operation in 2020 — a quarter of which were fast-chargers (at least 22kW) — and that more than 1,000 public chargers of up to 300kW are now available in Europe.
Plötz suggests that recent technological developments mean that FCEVs no longer have a raison d’être.
“When battery electric vehicles had limited range[s] of under 150km, and charging took a few hours, there was an important and large market segment for fuel-cell vehicles: long-distance travel. The higher energy density of compressed hydrogen, compared with battery electric vehicles, and the ability to refuel within only a few minutes, made fuel-cell vehicles potentially ideal for frequent long-distance trips. But battery electric vehicles now offer about 400km real-world range and the newest generation use 800V batteries, which can be charged for a range of 200km in about 15 min[utes].
He adds: “Many of the ongoing investments in hydrogen cars seem to follow the sunk cost fallacy: we have already spent so much on this technology, let’s not give up now.
“But with economies of scale in full effect for batteries, and with further cost reductions and performance improvement of electric vehicles and charging infrastructure coming, fuel cell cars are highly unlikely to be able to compete.”
Trucks
The hydrogen-fuelled trucking sector is also less advanced than the battery-powered, Plötz says, pointing to 30,000 battery-electric trucks in stock globally, most of which are in China.
“Fuel cell electric trucks, on the other hand, have only been operated in test trials (from two manufacturers) to date and are not yet commercially available,” he explains, adding that more than 150 battery electric truck models have already been announced for medium and heavy freight.
“The current challenge for battery electric vehicles is long-haul logistic operation (with an average of 100,000 km per year) and transport of very heavy goods (which implies high energy consumption per kilometre),” Plötz writes. “This is the use case often discussed for hydrogen trucks. Several truck manufacturers, as well as fuel-cell and infrastructure providers, have joined forces and announced a target of 100,000 fuel-cell trucks on European roads by 2030.
“But this seems very unlikely when contrasted with announcements from the companies about the earliest start date for the production of commercial series fuel-cell electric trucks being in 2027. By that time, the second-generation battery electric vehicles will already be commercially available and in operation.”
He explains that while long-haul trucking of more than 500km per day “poses a challenge” for battery-electric options, European regulations mean truck drivers are required to stop for a 45-minute break after driving for more than four-and-a-half hours.
“Within 4.5 hours, a heavy truck could travel up to around 400km and thus practical [battery] ranges of about 450km would suffice, if high-power fast charging for battery electric trucks was widely available,” Plötz says.
“Charging 400km in 45 min for a heavy truck means about 800kW average charging power. The current fast-charging standard... allows up to 350kW. But a new megawatt charging system standard is under development, which should allow over 2MW charging; specifications are expected for the end of 2022, with a final standard in 2023. Truck manufacturers are pushing for the construction of a megawatt charger network in Europe and potential locations for fast chargers have been proposed.
“A draft infrastructure proposal in Europe has suggested that high-power chargers every 50km along the main highway network are required.”
Plötz, who has been researching clean transport since 2011, points to studies suggesting than the total ownership costs for fuel-cell trucks would be higher than for battery-powered models with megawatt charging, adding: “For trucks, operating costs are more important than for cars, making the use case for fuel cell electric trucks even smaller.”
Nevertheless, H2 trucks could still have a practical advantage for “really heavy transport in remote areas”, he explains, adding: “But the question remains: are such niche areas large enough to sustain the commercialization and the economies of scale required to produce fuel cell electric trucks and their infrastructure?
“Depending on the specific size of the niche, biofuels or renewable synthetic fuels might be sufficient after 2030 to operate the application with carbon neutrality.”
Plötz concludes: “If truck manufacturers do not start the mass production of fuel cell trucks soon to reduce costs, such vehicles will never succeed in low-carbon road transport. Policymakers and industry need to decide quickly whether the fuel-cell electric truck niche is large enough to sustain further hydrogen technology development, or whether it is time to cut their losses and to focus efforts elsewhere.”
