The use of hydrogen as a source of energy has sparked controversy. It is promoted as a non-polluting alternate source of clean energy. Nonetheless, producing and storing hydrogen is a high-energy process, raising doubt on its practicality as a green option. According to a new study, hydrogen has yet another severe drawback: it releases greenhouse gases when released into the environment. It could be 11 times worse for the climate than CO2.
Vehicles that run on batteries have already proven superior and have gained widespread adoption. However, hydrogen continues to be a popular alternative to fossil fuels in other uses such as maritime transportation, heavy vehicles, trains, and industrial applications.
Considering its many advantages, hydrogen has certain negatives. To begin with, producing hydrogen without releasing greenhouse gases is incredibly challenging. Moreover, fossil fuels provide the great bulk of hydrogen. The rest is obtained through water electrolysis, which necessitates a significant quantity of electric energy, supplied primarily from the combustion of fossil fuels. So, in either case, it falls short of the green goals.
According to a new UK Government study, hydrogen’s Global Warming Potential (GWP) is about twice as bad as previously understood; over 100 years, a ton of hydrogen in the atmosphere will warm the Earth some 11 times more than a ton of CO2. This is because hydrogen reacts with other gases and vapours in the air, causing significant heating effects.
Another study by Frazer-Nash Consultancy revealed that compressed gas cylinders lose 0.12-0.24 percent of their volume every day, while hydrogen delivered as a cryogenic liquid loses nearly 1% each day. This makes its way to the upper atmosphere, where it reacts with the same tropospheric oxidants that “clean up” methane emissions.
Methane concentrations rise as a result, and methane stays in the atmosphere for more extended periods of time. The presence of hydrogen also enhances tropospheric ozone and stratospheric water vapour concentrations, raising temperatures so much more.
Notwithstanding the findings of the UK study, even if the hydrogen leakage rate reaches 10%, using hydrogen will counterbalance a 4% reduction in carbon emissions. This is still a significant improvement over the use of fossil fuels.
“Whilst the benefits from equivalent CO2 emission reductions significantly outweigh the disbenefits arising from H2 leakage,” the study states, “they clearly demonstrate the importance of controlling H2 leakage within a hydrogen economy.”