The hydrogen used as fuel directly in engines is being used as a clean substitute for these, since the residue that comes out of the exhaust pipe does not generate greenhouse gases. However, producing and storing hydrogen consumes energy, calling into question its potential as a green solution. A study by the UK government shows that hydrogen have another big problemsince it becomes a greenhouse gas when it is released into the atmosphere which in the long term would make it more harmful than CO emissionstwo.
In the case of light passenger vehicles, battery-powered electric propulsion has proven to be a viable solution that seems to prevail over solutions that use hydrogen. This can be used to create electricity through an ion exchange cell or directly as fuel.
For other applications such as shipping, heavy trucks, trains, and industrial applications, hydrogen still holds promise as a clean alternative to fossil fuels. It is also an almost instant replacement for other gaseous fuels such as methane or propane.
Although all its advantages, hydrogen also has some drawbacks. The most important is in its production. It is very difficult to obtain it without generating greenhouse gases. In fact, most of the hydrogen, about 95% (as of 2020), is produced from fossil fuels. The rest is obtained by water electrolysis for which a large amount of electrical energy is required, which is also produced for the most part by burning fossil fuels. production. Therefore, its advantages are not such unless it is green hydrogen, which is the one that is generated from sources of renewable energy.
But hydrogen has another problem that scientists have overlooked. According to a new study commissioned by the UK governmentall tanks that store hydrogen leak, and the leaking gas is worse for the environment than COtwo. Over a period of 100 years, one ton of hydrogen released into the atmosphere will warm the Earth 11 times more than a ton of COtwo. This is because hydrogen interacts with other gases and vapors in the air to produce powerful heating effects.
According to another studycompressed gas tanks they lose about 0.12-0.24% of their volume per daywhile hydrogen transported as a cryogenic liquid loses about 1 %. This reaches the upper layers of the atmosphere, where it interacts with the same tropospheric oxidants that “clean” the methane emissions. This leads to higher concentrations of methane and it staying in the atmosphere longer. The presence of hydrogen also increases the concentration of both tropospheric ozone and stratospheric water vapor, further raising temperatures.
Despite these findings, even in the worst case, where the hydrogen leak rate reaches 10%, the use of hydrogen will offset a 4% reduction in carbon emissions, which is still a huge improvement over using fossil fuels. What the study does clearly demonstrate is “the importance of controlling hydrogen leaks when you want to create an economy based on it.”