Multiple hydrogen production pathways needed to meet midcentury carbon goal

Blue and green hydrogen will both become critical to a net-zero carbon future, helping the global energy industry to meet emissions reductions targets across its entire value chain, a panel of industry experts said from the S&P Global Platts 2nd Annual Hydrogen Markets Americas Conference.

While often framed as competing technologies, blue and green hydrogen actually offer unique solutions to both cost and infrastructure challenges posed by the growing immediacy of the energy transition.

In the production of energy, green hydrogen offers the promise of cost-efficient energy storage.

Produced via PEM electrolysis fueled by renewable power, green hydrogen can be stored in underground salt caverns or depleted wells and later burned to produce zero-carbon power.

"Green hydrogen is not cost competitive with other fuels currently," said Paul Browning, president and CEO, Mitsubishi Power Americas. "But, if you look at it as an energy storage technology, its actually very affordable today in comparison to lithium ion technology – if your use case is to store electricity for more than eight hours."

Rapidly advancing lithium ion technology has dramatically lowered the cost of stored renewable power in recent years. For even the most efficient utility-scale batteries, though, discharge capacity remains time restricted to a relatively short four-to-six-hour time period, making seasonal or even diurnal battery storage impractical.

According to Browning, the zero-carbon storage capability of green hydrogen could also dramatically reduce the need for additional and costly buildout of solar, wind and battery infrastructure, helping to lower overall costs in the transition toward a decarbonized energy industry.

For end-users, the high cost of green hydrogen has thus far limited its widespread adoption, posing challenges for its use as a fuel for power generation, residential-commercial heating or transportation.

In contrast, existing technologies and infrastructure could allow blue hydrogen to be adopted quickly and at a relatively low-cost, according to Al Rettenmaier, executive director at E3 Consulting.

The zero-carbon fuel can be readily produced via methane reforming of natural gas in combination with carbon capture and storage, or CCS, – both existing technologies that are already in use today.

Key to the adoption of blue hydrogen is the immediate need for a zero-carbon fuel where electrification is impractical or costly – use cases like shipping or industrial and residential-commercial settings. As Capella Festa, chief operating officer at Genvia noted, global energy consumption will be difficult to fully electrify over the near term given that 80% of the world's energy is currently consumed as a molecule, compared to just 20% in the form of an electron.