In February 1923, futurist John Haldane delivered a lecture at Cambridge University on
wind farms that would provide England with clean and cheap electricity to produce hydrogen; he also envisioned
the use of underground hydrogen storage to supply energy when the wind was not available (Haldane, 1923).
Since then, there have been several attempts (for example, during the oil crisis of the 1970s) to scale up hydrogen,
particularly as a clean fuel to replace oil.
Each occurrence of a “hydrogen wave of interest” marked a distinct
phase in the exploration and development of hydrogen as a viable energy solution (see section 2).
The most recent phase is linked to international efforts to avert dangerous climate change. Countries around the
world agreed in 2015 that rapid decarbonisation is needed and adopted the historic Paris Agreement. According
to the Intergovernmental Panel on Climate Change (IPCC), human activities have unequivocally caused global
warming, and in the last decade the average global surface temperature reached 1.1 degrees Celsius (°C) above
pre-industrial levels. Based on the findings of Working Group III of the IPCC’s Sixth Assessment Report, global
temperature is likely to exceed 1.5°C of pre-industrial levels this century, based on current global targets expressed
in National Determined Contributions (NDC), and even limiting warming to below 2°C would rely on a rapid
acceleration of mitigation efforts after 2030.
The global consensus now is that hydrogen and its derivatives – produced in ways that yield low life-cycle
greenhouse gas emissions (i.e. “clean hydrogen”) – are part of the overall decarbonisation puzzle. They are a key
solution to decarbonise hard-to-abate sectors, as well as for the large-scale, long-term storage and transport
of clean energy. The role of clean hydrogen (see Box 2 for definitions) and its derivatives in industry to reach
net-zero greenhouse gas emissions, and in mitigating emissions in the transport sector, were highlighted in the
latest IPCC report on mitigation of climate change