IFP Energies Nouvelles (IFPEN) has become one of the earliest global research centres to actively investigate onshore natural hydrogen emissions.
Initial exploratory works have already shown that continuous onshore natural H2 emissions occur frequently. Now IFPEN is launching a new research project to investigate the viability of industrial exploitation, a possibility that has lain dormant since the discovery of offshore sources in the 1970s.
Currently, hydrogen is produced of converting other resources. The H2 used in industry is mainly produced by converting natural gas (CH4), which has the downside of emitting CO2. In the future, hydrogen produced through water electrolysis of water is expected to be a major source, for use in energy storage.
However, growing evidence is pointing to the existence of substantial, natural emissions of hydrogen. The significance of this is that hydrogen could become a source of energy, instead of a carrier, but unlike other fossil fuels its use would emit water instead of CO2. The question now being asked is whether it is sustainable. This is currently at the very heart of IFPEN’s research.
Natural emanations of hydrogen were first discovered along mid-ocean ridges on the seabed (the so-called "black smokers" and "white smokers"). In this environment, volcanic systems create hydrothermal circulation, bringing together sea water and peridotites – highly reduced rocks from the Earth’s mantle – at high temperatures. The peridotites oxidise upon contact with the sea water, and the reduction produces hydrogen. Unfortunately, these "smokers", are located at deep sea level, far from the coasts, and exploiting them is not economically viable.
IFPEN has therefore focused its research on more accessible, onshore sources of H2, which have been observed in two geological settings -terrestrial mountain ranges containing peridotites, where specific tectonics expose the mantle-derived rocks to alteration by meteoric water, and intracontinental regions (intraplate regions) and in particular in the oldest parts (Precambrian cratons) located at their centre.
While scientific literature makes occasional reference to these hydrogen emanations, until now they have never been explored in detail.
IFPEN’s initial research proved the existence of major local flows of H2 in major peridotite mountain ranges all over the world. More importantly, it demonstrated hydrogen flows were a common feature in intraplate regions. Despite the flows being sparse on most sites, substantial local accumulations were identified in some areas. The various natural fluids studied can present up to 80% of H2. It is often associated with methane, occasionally nitrogen and, in some places, economically viable quantities of helium, at a time when demand for this rare gas with numerous high-tech applications is stretching global supplies to their limit.