When hydrogen(氢气) burns, the only by-product is water—which is why hydrogen has been an attractive zero-carbon energy source for decades. Yet the traditional process for producing hydrogen, in which fossil fuels are exposed to steam, is not even remotely zero-carbon. Hydrogen produced this way is called gray hydrogen; if the CO2 is captured and sequestered (封存), it is called blue hydrogen.
Green hydrogen is different. It is produced through electrolysis (电解), in which machines split water into hydrogen and oxygen, with no other by-products. Historically, electrolysis required so much electricity that it made little sense to produce hydrogen that way. The situation is changing for two reasons. First, significant amounts of excess renewable electricity have become available at grid(输电网)scale; rather than storing excess electricity in arrays of batteries, the extra electricity can be used to drive the electrolysis of water, “storing” the electricity in the form of hydrogen. Second, electrolyzers are getting more efficient.
Current renewable technologies such as solar and wind can decarbonize (脱碳) the energy sector by as much as 85 percent by replacing gas and coal with clean electricity. Other parts of the economy, such as shipping and producing, are harder to electrify because they often require fuel that is high in energy density (密度) or heat at high temperatures. Green hydrogen has potential in these sectors. The Energy Transitions Commission, an industry group, says green hydrogen is one of four technologies necessary for meeting The Paris Agreement goal of decreasing more than 10 gigatons of carbon dioxide a year from the most challenging industrial sectors, among them mining, construction and chemicals.
Although green hydrogen is still on the early stage of its development, countries—especially those with cheap renewable energy—are investing in the technology. Australia wants to export hydrogen that it would produce using its plentiful solar and wind power, Chile has plans for hydrogen in the country’s dry north, where solar electricity is abundant. China aims to put one million hydrogen fuel-cell vehicles on the road by 2030. All of which is why, earlier this year, Goldman predicted that green hydrogen will become a $ 12-tilion market by 2050.
【小题1】What do we know about green hydrogen?| A．It can be made from fossil fuels. |
| B．It can be extracted from blue hydrogen. |
| C．It consumes little electricity when produced. |
| D．It releases nothing except water when burning. |
| A．Enough electricity and efficient device |
| B．The extending life and capacity of batteries |
| C．The lower cost of different clean energies |
| D．Financial support from all sectors of society |
| A．The potential of current green energy |
| B．The necessity of reducing carbon dioxide |
| C．The advantages of green hydrogen |
| D．The results of using wind and solar power |
| A．worried | B．optimistic | C．doubtful | D．pessimistic |
