Ten years ago, there seemed to be two possible substitutes for fossil fuels in personal transportation: electricity and hydrogen. Hydrogen presented itself as a very promising option. You could refuel like with a fossil fuel. The exhaust gases would be just pure water vapor instead of harmful gases. This seemed to be the perfect way forward for a greener future where we could continue to use our vehicles as before, but without the environmental inconveniences. Hydrogen seemed to be the most practical option compared to waiting to recharge an electric vehicle battery.
Ten years later, however, there is no doubt that battery electric vehicles (EVSs) are dominating the shift towards more environmentally friendly transport. By the end of 2019, only 7,500 hydrogen cars had been sold worldwide. But by the end of 2018, there were already more than 5 million plug-in electric vehicles (ESTs), and sales have accelerated considerably since then. The VEB segment in this sector has never been less than 55% and is now 75%. In the United Kingdom, according to the Society of Motor Manufacturers and Traders, VEBs accounted for up to 4.3% of the global automotive market as of May 2020; an increase of 131.8% since 2019. VEBs are starting to be a problem for fossil fuel cars, and their fuel cell alternatives are driving nowhere.
Toyota was a company that truly believed in the future of hydrogen, and produced the highly credible FCV-R concept in 2011 that gave birth to the Mirai – which became commercially available in 2015. A second generation will be released in 2021. Honda also produced two fuel cell vehicles, the Clarity Fuel Cell and the FCX Clarity. Hyundai owns the Tucson fuel cell. So there are several choices, and these vehicles are all perfectly viable for everyday use, the Mirai offering a range of approximately 500 km (312 miles) with its tank, and the Honda Clarity fuel cell running a very healthy 585 km (366 miles).
So why didn’t hydrogen fuel cell vehicles take off in the same way as VEBs, given their usefulness? June 2019 could be the month when there were scribbles on the wall. A hydrogen-producing chemical plant in Santa Clara had just exploded, leaving fuel cell users in California running out of fuel. A few days later, a supply station in Sandvika, Norway, also caught fire. It really made us realize that hydrogen can be a dangerously explosive gas – to believe that we didn’t already know! I have not heard of any cases of car explosions. In addition, the fuel tanks are now lined with Kevlar to protect them from the possibility of explosion. But it was not a series of confidence-building events.
However, safety concerns are not the main reason why hydrogen is a much lower option than VEBs. If one of your main goals is to save the planet, VEBs are significantly more energy efficient than fuel cell vehicles if all the steps between power generation and propulsion are taken into account. With a VEB, once the electricity is generated – hopefully from a renewable source – the power supply to your vehicle loading location loses about 5%. The battery charge and discharge then lose another 10%. Finally, the engine still wastes 5% while driving the vehicle. This represents a total loss of 20%.
With a hydrogen fuel cell, you must first convert electricity into hydrogen by electrolysis, which is only 75% efficient. Then the gas must be compressed, cooled and transported, resulting in an additional 10% loss. The conversion process (hydrogen to electricity through the fuel cell) is only 60% efficient. In the end, you have the same 5% loss using this vehicle as a VEB. In total, the loss is 62%, more than three times as many. In other words, for every kW of electricity supplied, you get 800 W for an VEB, but only 380 W for a fuel cell vehicle, or less than half. This is a huge inefficiency if you hope for a greener future, and it doesn’t even take into account the fact that 95% of hydrogen is currently produced from fossil fuel sources.
Nevertheless, hydrogen still has niches where its main advantages – lightness and speed of refuelling – give it a clear advantage. If you can adapt your personal driving style to strategic stops to recharge the battery, it’s not ideal for a utility vehicle that has to drive for very long periods of time and over very long distances and has only a short wait to refuel. The weight of the batteries for eight hours of continuous use would also be prohibitive on a train, for example. Thus, for industrial vehicles, hydrogen seems to be a viable option, despite its inefficiency. However, in the UK, there were only ten hydrogen buses in service in March 2019, along with 155 electric buses (and others arriving) and 3,669 hybrid buses. But a two-stage hydrogen bus is also in service in London as well as hydrogen diggers and trains. Nikola Motor, the stock market darling, works on hydrogen semi-trailers, as well as electric and hybrid variants.
But for personal car users, this is no small feat. Hydrogen evangelists continue to argue that light commercial vehicles are the future of personal transportation and that this technology will take off in 2020. It is likely that the energy supply chain efficiency of fuel cell vehicles will improve over time and that more renewable energy sources will be used for hydrogen production. However, given the number of VEBs already in circulation, fuel cell vehicles have already lost this battle and will never catch up. A VEB is a viable personal means of transport in most developed Western countries today. There are many options with a range of more than 200 miles, and the Tesla has even reached 600 km (400 miles). Recharge points are constantly appearing, with more than double charging points for electric vehicles in the UK than petrol stations. The battle for the future of green personal transport is over, and VEBs have already won.