An example of reflexive and ethical work on a geoscientific speculation bubble: the case of natural hydrogen

Recently, in the context of intensifying calls for a rapid decarbonation of the economy and energy systems, there has been a growing interest in developing the use of hydrogen, either as a fuel or as an energy storage system. However, hydrogen production suffers from various drawbacks, due to its carbon footprint or cost, which has led the field of geosciences to renew its interest in the possibility to collect naturally occurring hydrogen (so called "white hydrogen"), found in gas reservoirs or in hydrothermal waters for example, or stimulate natural production of hydrogen before harvesting it (so called "orange hydrogen").
Querying the Web of Science database, the average number of annual scientific publications including "natural hydrogen" in their title or abstract, was steady around 2 between 1984 and 2016, it was 6 over 2017-2019, 16 over 2020-2022 and reaching 27 in 2023, thus appearing to follow an exponential growth. Similarly in media in France we retrieved 37 articles mentioning "natural hydrogen" between 2010 and 2019, with terms such as "infancy", "pilot project" or "future energy?" , while there were 44 between 2020-2022 and 227 in 2023 alone, with terms such as "rush", "game changer", "revolution" or "bright hopes".
This exponential growth and the rapid shift toward very enthusiastic vocabulary make us hypothesize that the rising interest in natural hydrogen is a process similar to an economic bubble, in which a commodities is over-valued during a transient period.
In this work we will present reflexive work based on an analysis of the recent scientific literature and on associated media coverage, on basic comparisons between energy available from recent H2 fluxes or estimated reservoirs and from other renewable energy sources, and on semi-directive interviews of some geoscientist specialists of hydrogen.
These elements allow us to confront this hypothesis and to gain insights on the intertwined effects that may favor the over-valuation of natural hydrogen. In particular, we also discuss reasons why geoscientists contribute, actively or not, to the growth of a speculative bubble, a mechanism generally associated with irrational market dynamics. We do so by exploring the potential roles of undeclared conflicts of interests, temptation to access facilitated research funding, lack of interdisciplinary analysis, and of the predominant belief that technological innovation or adjustments is needed and sufficient to address the ecological emergencies.