The transport sector is responsible for 25% of all direct CO2 emissions on our planet, with cars, buses and motorbikes accounting for three quarters of them. The rest of the pollution comes from aviation and freight transport, the sectors that have experienced some very strong growth recently. Rail transport is the most efficient mode of transport and accounts for only 2% of the energy used in transport.
This means that to comply with the Paris Agreement and contain global warming by 2100, governments, industry and investors will need to focus a great deal on finding alternative energy solutions particularly in road transport and aviation. So here we decided to take a plunge and summarise industry forecasts on when hydrogen-based solutions for transport may become a viable alternative
Automobiles
Cars and trucks of various types are accountable for most of green house gases (GHG) emitted by all forms of modern transportation. Consequently, the European Union (EU) imposes very ambitious intermediate targets aimed at encouraging manufacturers to explore different solutions. Will hydrogen be part of them compared to conventional or electric engines? The investment costs for developing new vehicles with combustion engines are currently the lowest but we believe that hydrogen-based engines will offer great potential for cost reduction if we look at the next 10 years.
As things stand now, for cost reasons, the competition for light vehicles is between combustion engines and electric cars and not with hydrogen fuel cells. According to the various scenarios of cost reduction, hydrogen could only become an alternative to combustion and electric engines for light vehicles around 2030.
For the so-called 'heavy' mode of transport, the size of the electric battery makes it less practical. For example, a 40-tonne battery electric truck with a range of 500 km requires eight tonnes of battery power, making it less practical for transporting goods over long distances. Hydrogen providing three times more energy per kg than diesel, even though the tanks are heavier, could be a solution in this case.
Heavy vehicles therefore offer better possibilities for using hydrogen given the weight of the battery required for long distance transport. As a result, projects for hydrogen-powered semi-trailers are already well advanced. Different studies show that, for heavy vehicles, hydrogen could become a commercially viable alternative to combustion and electric engines in the course of the next ten years.
Aviation
While planes’ CO2 emissions represent only about 2.5% of global emissions, experts believe that the estimates should be at least doubled. This is because the steam released by planes at high altitudes is also a significant greenhouse gas.
Hydrogen-based liquid fuels could offer an alternative to aircraft fuel. This would require combustion turbines rather than a fuel cell, as it does not have the power to lift a plane into the air. Storage would require changes in aircraft design and infrastructure. Given the higher costs of hydrogen, this would require a carbon price above 115USD/tCO2 to be competitive (source Bernstein). Therefore, hydrogen seems far from being able to replace kerosene, with only the most optimistic scenarios expecting it to become a viable alternative for planes not earlier than 2045.
Ships
Ships consume about 5% of global oil demand and contribute about 2.5% of global CO2 emissions, with freight using heavy fuel oil. Maersk is the first shipping company to announce its intention to become carbon neutral by 2050. This will require zero-carbon ships to be available by 2030. But switching to hydrogen is and will be very expensive for the sector, not only in terms of the hydrogen fuel costs but also the new infrastructure that would be required. Most experts forecast that the tipping point in terms of competitiveness in this sector would come only after 2030.
Trains
Rail is one of the most energy-efficient modes of transport, accounting for 8 per cent of motorised passenger movements and 7 per cent of freight worldwide, but only 2 per cent of transport energy consumption. Rail is responsible for only 0.3% of CO2 emissions. However, hydrogen trains have been deployed on a trial basis and are currently under development. Experts believe that for this mode of transport, hydrogen will become a commercially viable alternative to diesel and battery electric sometime before 2030.