A mountain of hydrogen lurks underground earth surface –Scientists say it would take just a fraction of that to break our 200-year dependence on fossil fuels.
New research shows that Earth contains about 6.2 megatons (5.6 megametric tons) of hydrogen in its rocks and underground reservoirs. This is about 26 times The amount of oil left in the ground is known (1.6 megabarrels, each weighing about 0.15 tons) – but where these hydrogen stocks are located remains unknown.
Researchers suspect that much of the hydrogen may be too deep or too far offshore to access, and that some reserves may be too small to extract in an economically sound way. However, the results show that even with these limitations, there is still enough hydrogen available, Jeffrey Ellisa petroleum geochemist with the U.S. Geological Survey (USGS) and lead author of the new study told Space.com sister site Live Science.
Hydrogen is a Source of clean energy It can fuel vehicles, power industrial processes and generate electricity. The study found that just 2% of hydrogen stocks, equivalent to 124 billion tons (112 billion metric tons) of natural gas, “could provide all the hydrogen we need to achieve net zero emissions” [carbon] Hundreds of years,” Ellis said.
Ellis and his co-authors say this hydrogen gas releases roughly twice the energy stored in all known natural gas reserves on Earth. Sarah Gelmanalso a geologist with the U.S. Geological Survey, noted in the study. The results were published in the journal on Friday (December 13) scientific progress.
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To estimate the amount of hydrogen in the Earth’s interior, the researchers used a model that takes into account how quickly the gas is produced underground, how much hydrogen may be trapped in reservoirs, and how much hydrogen is lost through various processes, such as leakage from rocks. amount.
Ellis said hydrogen is produced through chemical reactions in rocks, the simplest of which is the splitting of water into hydrogen and oxygen. “There are literally dozens of natural processes that produce hydrogen, but most of them produce very small amounts,” he said.
Until recently, researchers didn’t realize that hydrogen was accumulating beneath the Earth’s surface. “My paradigm throughout my career has been that hydrogen is out there, it happens, but it’s a very small molecule, so it can easily escape through small pores and cracks and rocks,” Ellis explains.
But when scientists discover a West Africa has huge reserves of hydrogenand then Another one is located in Albania chrome minethis paradigm shifted. It is now clear that hydrogen does accumulate in Earth’s reservoirs, and new research suggests that some of these accumulations may be quite large.
“I was surprised that it turned out to be bigger than I thought,” Ellis said. “The conclusion is, there’s a lot of stuff down there.”
But he said it was important to note that there was huge uncertainty surrounding these results because models suggested there could be between 1 billion and 10 megatons of hydrogen out there. (Based on the model’s assumptions, the most likely value is 6.2 megatons.)
Hydrogen energy is expected to account for as much as 30% of future energy supply in some industries, and global demand is expected to will increase fivefold by 2050. This gas is produced artificially through electrolysis of water, where water molecules are split apart by an electric current. When renewable energy is used, the product is called “green hydrogen” and when fossil fuels are used, the product is called “blue hydrogen.”
The benefit of utilizing natural hydrogen is that it requires no energy to produce, and underground reservoirs can store the natural gas until it is needed. “We don’t have to worry about storage, it’s like blue hydrogen or green hydrogen — you want to make it when electricity is cheap, and then you have to store it somewhere,” Ellis said. With natural hydrogen, “You can open the valve and close it when you need to.”
The big question that remains is where all this hydrogen is located, which will affect whether it is accessible. Ellis and his colleagues are working to narrow down the geological criteria needed to form underground deposits, and U.S. results could be available early next year, he said.