The H2 Phantasm

“…one potential idea, which is not talked about much, is hydrogen as a fuel for cars. It already works well and is being developed further as we speak. Why is that not being endorsed and supported massively? It’s entirely 100% clean…“

People on the Internet

To create useable hydrogen, you currently have to use electrolysis. 9 kg of water takes about 50kWh of energy to convert into 1 kg of H2 and 8KG of O2¹. The three commercially-available hydrogen fuel cell cars (FCVs) – Toyota Mirai, Honda Clarity and Hyundai Nexo – can each take about 6 KG of hydrogen and they have roughly 40 % efficiency, already better than the Internal Combustion Engine (ICE) efficiency of 20-30 %, but short of the Battery Electric Vehicle’s (BEV) 70-85 %.

50kWh is enough to recharge some BEVs completely already, and 300 kWh is enough to refuel one Mirai, or six BEVs largely. The end goal of charging vehicles also needs two other things to be taken into consideration for both BEVs and FCVs. How to generate, and how to transport.

For generation, both are compromised if you don’t use clean energy, but that’s concentrated for H2 if you need six times as much. There’s a lot of what’s called “grey” and “blue” hydrogen that is generated using coal and gas. There’s also “turquoise” hydrogen generated with pyrolysis, but the only one that can be considered good is “green” hydrogen, generated using power from renewable sources².

For transport, electricity already has an extensive network – even if it has to be slow charging from a domestic supply. The charging network is still under-resourced but rapidly improving around the world. Hydrogen has to be transported by pipeline, rail or road – all at a further energy cost, and risk of pollution and emission of CO2. In addition, if it’s going to cost so much energy to electrolyse water, why not skip the middleman and just charge BEVs directly? People say that the only waste product is H₂0, which is true, but what happens to that water? It’s not recovered for further use. It just dribbles out of the exhaust and is wasted.

All this is not to say there’s no place for hydrogen! For industry, mass transport and aviation there are great advances occurring. It’s just that it’s a dead-end for personal transport. JCB seems to have a pretty good handle on things here:

ICE engines and burning stuff does not just create pollution (as if that were not bad enough in itself), but also contribute to the amount of CO2 in the atmosphere, which is one of the principal causes of the greenhouse gases that are causing climate change

One of the other points people bring up is how filthy shipping is and I completely agree. It is disgusting how shipping companies use the lowest grade possible of diesel to cut costs with all the pollution that causes in the sea. This would be a great place to see hydrogen engines in use. An example of this is the ferry between Germany and Denmark that I took three years ago. It was running on hydrogen engines that were quiet and pollution-free and the smoke pouring from the chimney stacks was just water vapour – a lovely thing to see

Standard shipping is also actually used to transport fossil fuels all over the world, using this low-grade diesel. Not only is it polluting, it’s transporting pollution.

In all cases, whether ICE, FCV or BEV, the solution for the climate crisis we find ourselves in is not more consumption. Adding a new vehicle to the road needs to be considered very carefully. In future, I see car ownership decline as TAAS (Transport As A Service) starts to take off. Cars are already not something the inexpert can fiddle with on the weekend and they will become less so as BEVs become the norm.

1. Conversion source
2. Hydrogen colours