Electromobility is picking up more and more speed. It is an important element in reducing CO 2 emissions from traffic. But how economical is it to operate heavy-duty trucks with 40-ton payloads over long distances using only battery-electric power? Given the battery weight, long charging times, and limited range of today’s technology, electric powertrains aren’t the first choice for heavy trucks. Nevertheless, even 40-ton trucks will be able to travel more than a thousand kilometers in all-electric mode in the near future. The key to this is the Bosch fuel-cell powertrain. When powered with hydrogen produced using renewable energy, this powertrain enables the climate-neutral transportation of goods and commodities. Bosch is taking the first step in this direction by developing the fuel-cell powertrain primarily with a focus on trucks, and the company plans to start production in 2022–2023. Once they have become established in trucks, Bosch fuel-cell powertrains will then increasingly find their way into passenger cars – rightly making them an integral part of tomorrow’s powertrain portfolio.
Seven reasons why fuel cells and hydrogen are crucial building blocks of tomorrow’s mobility:
1) Climate neutrality
In a fuel cell, hydrogen (H 2 ) reacts with oxygen (O 2 ) from the ambient air. The energy this reaction releases is converted into electricity, which is used for driving. Heat and pure water (H 2 O) are other products of the reaction. H 2 is obtained using electrolysis, in which water is separated into hydrogen and oxygen with the aid of electricity. Generating this electricity from renewables makes the fuel-cell powertrain completely climate-neutral. Especially for large, heavy vehicles, fuel cells have a better carbon footprint than exclusively battery-electric powertrains if the CO 2 emissions for production, operation, and disposal are added together. All that fuel-cell vehicles need in addition to their hydrogen tank is a much smaller battery for intermediate buffer storage. This greatly reduces their carbon footprint in production. “The advantages of the fuel cell really come into play in those areas where battery-electric powertrains don’t shine,” explains Dr. Uwe Gackstatter, president of the Bosch Powertrain Solutions division. “This means there’s no competition between fuel cells and batteries; instead, they complement each other perfectly.”
2) Potential applications
Hydrogen has a high energy density. One kilogram of hydrogen contains as much energy as 3.3 liters of diesel. To travel 100 kilometers, a passenger car needs only about one kilogram; a 40-ton truck needs a good seven kilograms. As with diesel or gasoline, it takes just a few minutes to fill an empty H 2 tank and continue the journey. “Fuel cells are the first choice for transporting larger loads for many kilometers every day,” Gackstatter says, summarizing the advantages. In the EU-funded H2Haul project, Bosch is currently working with other companies to build a small fleet of fuel-cell trucks and put them on the road. In addition to mobile applications, Bosch is developing fuel-cell stacks for stationary applications with solid-oxide fuel-cell (SOFC) technology. One intended use for them is as small, distributed power stations in cities, data centers, and charge points for electric vehicles. If the Paris climate action targets are to be met, in the future hydrogen will need to power not only cars and commercial vehicles, but also trains, aircraft, and ships. The energy and steel industries are also planning to make use of hydrogen.
3) Efficiency
One of the decisive factors for a powertrain’s eco-friendliness and profitability is its efficiency. This is around a quarter higher for fuel-cell vehicles than for vehicles with combustion engines. Employing recuperative braking further increases efficiency. Battery-electric vehicles, which can store electricity directly in the vehicle and use it for propulsion, are even more effective. However, since energy production and energy demand do not always coincide in time and location, electricity from wind and solar plants often remains unused because it cannot find a consumer and cannot be stored. This is where hydrogen comes into its own. The surplus electricity can be used to produce it in a decentralized way, ready for flexible storage and transportation.
