Hydrogen: an appeal to reason

These remarks were made by Jan Rosenow during an IRENA workshop on hydrogen in the gas grid on 14 December 2021.

People often ask me whether I’m for or against hydrogen. But that is the wrong question to ask.

Instead the question should be “In which use cases can hydrogen deliver decarbonisation where other solutions are either not available or more costly?” Asking this question means that rather than thinking about decarbonising gas we think about decarbonising gas end-uses currently served by fossil gas.

This requires careful techno-economic analysis. There are excellent examples where this has been done. Ideally such analysis would not only assess the capital costs and running costs of different technology alternatives, but also include the wider energy system costs and benefits such as the impact on the power grid, the impact on air quality and wider social costs and benefits. Too often analysis put forward falls short of taking into account all of the costs and benefits.

What the evidence suggests is that hydrogen is going to play a very important role in the energy transition and for achieving our climate goals. We will need a lot of hydrogen in a broad number of applications. But it is important to also point out that at the moment we are not remotely close to even delivering sufficient quantities of green and low-carbon hydrogen to replace existing highly carbon intensive hydrogen applications. More than 95% of global hydrogen production are currently based on coal and gas with no carbon capture.

Numerous studies on hydrogen have been carried out, some more detailed and robust than others as you would expect. I reviewed many of those assessments and what I found is that the majority of studies agree on the no regret options hydrogen such as using it for fertiliser production where few alternatives exist and where it is already used today. There also seems to be fairly widespread agreement that hydrogen will most likely play a role in maritime shipping, long-haul aviation, high-temperature industrial processes, and electricity generation to balance the power system as we integrate more renewable energy sources, although some experts disagree. The main areas where at first glance there appears to be substantial disagreement is the use of hydrogen in road transport and comfort heating.

But what we found is that once you disregard the studies carried out on behalf of industry including the gas industry, electric utilities, heating system manufacturers, car manufacturers etc. the picture becomes a lot clearer. I have collected all independent studies on the use of hydrogen for heating buildings and not a single one of them identifies hydrogen as an economic option for decarbonisation of heating. Most recently, the IEA in its Net Zero 2050 report modelled that less than 2% of global comfort heating demand will be based on hydrogen. Instead, electrification and energy efficiency are commonly identified as superior alternatives because of the much greater efficiency of a factor of around 5. Suggesting that hydrogen is the superior technology for comfort heating is difficult to justify and where it has been pushed it is often driven by industry interests. The danger I see is that this can delay the energy transition and slow down the uptake of technologies we know will deliver carbon reduction at lower cost. Instead, we should focus on those applications where we are certain that hydrogen is likely to play an important role.?

Finally, I also want to briefly comment on the kind of hydrogen we should prioritise. Green hydrogen is clearly superior to blue because it can be zero carbon whereas blue hydrogen even with very high capture rates and low leakage rates will still result in significant emissions. If used in large quantities, this is not consistent with net zero climate goals.