Where next for hydrogen?

 

Major interest in hydrogen emerged during the 1970’s following the two ‘oil crises’ where the global availability of oil suddenly dropped and economies built around oil consumption, in particular America, went into sharp recession. Around the same time scientists and engineers began to realise that the economy could be redesigned to run on hydrogen, instead of oil, and the now famous phrase, ‘the hydrogen economy’, was born.

Versatility was key for the early champions of hydrogen. It was able to be burnt to produce heat, or be fed into a fuel cell to produce electricity, and if that fuel cell was in a vehicle with an electric motor then it could also deliver mobility. In the hydrogen economy vision all the sectors that were currently dependent on oil or other fuels would be able to switch to hydrogen, which can come from many sources. Its great attraction was the resilience it would provide to a supply shock in any one fossil fuel. 

But, following the hydrogen hype of the 70’s, reality soon cut in.  At first the dream was let down by the technology. Whilst all of the required components worked to a degree, they were always too expensive, or unreliable, or fragile to compete effectively with the fossil fuel status quo. The tipping points in performance and cost which would allow the mass hydrogen roll out seemed always ‘just over the horizon’ but never quite came.  While we waited the world changed.

In the 90’s the world awoke to the fact that an energy system dominated by the burning of unabated fossil fuel is unsustainable. The energy system of the future will be dominated by renewable sources of energy, nuclear and CCS, which deliver most of their energy via electricity; the most versatile of energy vectors. A new phrase, ‘the all-electric future’, was born and this changed everything for the future of hydrogen.

Proponents of an all-electric future went on the attack.  Why take perfectly good low carbon electricity, convert it into hydrogen, compress it, distribute it and then turn it back into electricity or burn it, encountering significant losses at every stage in the process, when you could use the electricity directly in an electric vehicle or heat pump with much higher overall efficiency?

Initially hydrogen proponents had no answer to this challenge. Research continued, and within certain niches it still looked promising, but the idea of an energy system dominated by hydrogen appeared to have died. However, cracks then started to appear in ‘the all-electric future’, and as it moved from a compelling vision towards an engineered reality everything got more and more difficult.

What if the output from our wind farms fluctuates faster than we can modulate our nuclear and CCS power stations? What if the wind doesn’t blow in a really cold week? What if consumers don’t want to adjust to the differences in behaviour that those electric vehicles and heat pumps will require? How much will it cost to upgrade the electricity wires up and down every street in the country?

These challenges do not make an all-electric future impossible, but they have provided a second chance for hydrogen technologies, because in each case, one possible solution to the challenge is hydrogen. The hydrogen solution might be less efficient, but if it leads to a low carbon energy system that is cheaper, more stable and easier to deliver that might be a trade-off worth considering.

These opportunities for hydrogen to gain a foothold have not gone unnoticed.  Across the UK and around the world public and private sector investors are developing and demonstrating hydrogen solutions to the energy system problems of the future: electrolysers optimised for balancing wind, injection of hydrogen into the natural gas grid, hydrogen burning turbines, and self-contained islands with complete miniature hydrogen energy systems.

But whilst hydrogen technologies are making rapid progress demonstrating the roles they could play in the energy system, we are still some way from answering the more fundamental question; do we need hydrogen at all, and if so how much of it do we need?

You could design a viable low carbon energy system with lots of hydrogen, or none, or any point in between. Choosing the best solution comes down to cost and energy security but the answer is still not clear.  Currently all we can say is that it seems likely that having hydrogen in the energy system will make it easier to integrate the other low carbon solutions. But given the scale of the investment needed whatever solutions we choose, this level of uncertainty is not good enough.

For now the priorities for hydrogen must be to keep improving our understanding of hydrogen’s role in the energy system so that we can make confident ‘no regrets’ investments, and to keep developing hydrogen technologies and demonstrating their capabilities, so that they can be rapidly brought to market if and when we decide we need them.

 

This article was originally published in BusinessGreen.