Of course, hydrogen is the most abundant element in the universe and is only used as an energy carrier, so it doesn't run out in a fuel cell. However, it doesn't exactly grow on trees either, and there are no underground “bags of hydrogen” from which we can simply extract it. Almost all jurisdictions that have objectively considered how to achieve zero emissions in all end uses have realized that the characteristics of hydrogen are necessary for all these sectors to have zero emissions. Once produced, H2 generates energy in a fuel cell and the fuel cell emits only water and hot air.
Therefore, it promises growth in the energy sector. Jack Brouwer, director of the National Fuel Cell Research Center at the University of California, Irvine, said that, ultimately, hydrogen would have to be manufactured with renewable energy to produce what the industry calls green hydrogen, which uses renewable energy to divide water into its constituent parts, hydrogen and oxygen. Keeping hydrogen fuel so cold requires specialized containers such as the one pictured on the left. Unless you live in California, a country that has taken the initiative to build infrastructure to support hydrogen supply, chances are you've never seen the option of filling your car with hydrogen the last time you were at the gas station.
While there are some ways to collect hydrogen as a by-product of other processes, it must generally be extracted from fossil fuels or electrolyzed water. For hydrogen to reach a liquid state that can be stored, transferred, and eventually used as fuel, a temperature of -423 degrees Fahrenheit (-253 degrees Celsius) is required. National Grid, together with Stony Brook University and the State of New York, are studying the integration of hydrogen into their existing gas infrastructure, although the project seeks to produce hydrogen using renewable energy. And that's because most of today's hydrogen production (115 million tons) burns fossil fuels, as seen in the graph below.
Nowadays, very little hydrogen is green, because the process of electrolyzing water to separate hydrogen atoms from oxygen consumes a lot of energy. While the idea of hydrogen as a fuel source widely used to power cars and generate electricity is a relatively new concept in response to the search for an alternative to oil, hydrogen fuel cells actually predate the internal combustion engine, which was invented in the mid-19th century. The Energy Policy Act of 1992 considers it an alternative transport fuel because of its ability to power fuel cells in zero-emission vessels. Hydrogen produced from fossil fuels could still act as a transition fuel, but would ultimately contribute “to a small extent to the sustainable hydrogen economy in general,” he said.
So yes, hydrogen may be the fuel source of the future, but tomorrow you'll probably still have to fill your car with old, regular gasoline. It is building the Holland Hydrogen I, which is being promoted as the largest renewable hydrogen plant in Europe. Rather, it is a means of storing energy, since pure hydrogen is not available on Earth in the quantities needed to power an entire energy economy. Jack Brouwer is director of the National Fuel Cell Research Center at the University of California, Irvine.