Daimler showcases hydrogen prototype

By Categories: NewsPublished On: Sunday 27 September 2020

Mercedes’ parent Daimler Truck has unveiled a prototype hydrogen-powered heavy tractor unit. The Mercedez-Benz GenH2 will have similar performance to its diesel-engined equivalent, but run on liquid hydrogen, which will be used by a fuel cell to drive electric traction motors.

Gross vehicle weight will be 40 tonnes, and claimed payload is 25 tonnes.

Daimler can draw on existing expertise for the development of liquid-hydrogen tanks, and is also cooperating closely with a partner, Volvo Group. The German company can also call on decades of experience with fuel cells from its passenger car division, which has now abandoned the technology.

In April this year, Daimler Truck AG concluded a preliminary, nonbinding agreement with the Volvo Group to establish a new joint venture for the development to series maturity, production and commercialisation of fuel-cell systems for use in heavy-duty commercial vehicles and other applications (Transport Operator 90).

Joining forces will decrease development costs for both companies and accelerate the market introduction of fuel cell systems, Daimler asserts. To facilitate the joint venture, Daimler Truck AG has brought together all Group-wide fuel-cell activities in the newly founded subsidiary Daimler Truck Fuel Cell GmbH & Co.

The use of hydrogen as a substitute for diesel raises questions over how it would be produced. Over the last year, energy supply firms have lobbied the UK government to commit to hydrogen as the key element of its target for the UK to be carbon neutral by 2050. This means using it a fuel for long-haul trucks and replacing natural gas with hydrogen in domestic heating.

But in a letter to the Times newspaper, David Cebon, professor of engineering at Cambridge University, said that hydrogen was far from a silver bullet.

“Much scientific evidence shows that widespread adoption of hydrogen (instead of electricity) for heating and heavy vehicles would be detrimental to the UK’s economy, its energy security and its decarbonisation commitments,” he wrote.

“Given that the fossil fuel industry’s preferred… solution would involve significantly increased natural gas consumption, it is not surprising that it is busy lobbying governments around the world for hydrogen.”

Producing hydrogen by extracting it from natural gas (methane) produces more CO2 than would be produced by just burning the gas, and hydrogen presents far more technical challenges in terms of storage and transportation than methane does.

The ‘carbon neutral’ way of producing hydrogen is to reverse the fuel-cell process and electrolyse it out of water. But a lot of electrical energy is required, as the process is only 50 per cent efficient.

According to the Times, it has been calculated that generating enough renewable electricity to power UK road transport with battery vehicles would require the allocation of 5,300 km² of land area to wind farms. To do the same with hydrogen created by electrolysis would require 18,000 km² of land. To put those figures in proportion, Greater London covers just 1,572 km² and the total land area of the UK is only 248,532 km².

In a Daimler press statement announcing the Mercedes-Benz GenH2 fuel cell concept truck, as well as the eActros and eActros LongHaul, Martin Daum, chairman of the board of management of Daimler Truck AG, said: “We are consistently pursuing our vision of CO2-neutral transport with a focus on the genuinely locally CO2-neutral technologies battery power and hydrogen-based fuel cells, which have the potential to succeed in the market in the long term.

“This combination enables us to offer our customers the best vehicle options, depending on the application. Battery power will be rather used for lower cargo weights and for shorter distances. Fuel-cell power will tend to be the preferred option for heavier loads and longer distances…”

“We have now set out the key technological specifications of our electric trucks so that the requirements are known to everyone involved at an early stage. It is now up to policymakers, other players and society as a whole to provide the right framework conditions.

“To make CO2-neutral all-electric vehicles competitive, regulatory and government action is needed, including the necessary infrastructure for charging with green electricity and for the production, storage and transport of green liquid hydrogen.”