How Green Hydrogen Can Keep the Ocean Blue

Transitioning the Shipping Industry Away from Fossil Fuels

This year, after years of delay due to the Covid-19 pandemic, the ‘super year’ for the ocean has finally kicked off. 2022 is host to a number of critical ocean-relevant conferences, including the Our Ocean conference, UN Biodiversity Conference, UN Ocean conference, the UNFCCC Subsidiary Body for Scientific and Technological Advice (SBSTA) Recurring Dialogue on the Ocean and Climate Change, and the UN Climate Change Conference (COP27). These conferences present crucial opportunities for countries, civil society, and industry to commit to concrete actions to limit global warming to 1.5 degrees Celsius compared to pre-industrial levels in order to avert the direst consequences of climate change.

With almost three-quarters of the Earth’s surface covered by blue, the ocean provides substantial solutions to help confront the climate crisis. A report commissioned by the High-Level Panel for a Sustainable Ocean Economy found that by 2050 ocean solutions could contribute as much as one-fifth of the annual greenhouse gas (GHG) emission cuts needed to limit global temperature rise to 1.5°C. To achieve this goal, we need to rapidly eliminate carbon emissions from the global economy, and in most cases, electrification and renewable energy sources present the best path forward. However, for hard-to-abate industries that are major emitters of greenhouse gases, such as cargo shipping across our ocean, the best route is to adopt zero-emission fuels coupled with energy saving measures on those voyages that are too long for electrification and battery power.

Recently, at the 7th annual Our Ocean Conference, co-hosted by the Republic of Palau and the United States, Ocean Conservancy and its partners at United Maritime Academy Services launched a new report, “Future Maritime Fuels in the USA – the options and their potential pathways.” This report discusses alternative shipping fuels and what a U.S. transition to those fuels would look like.

If we want to meet the crucial Paris Agreement global temperature goals, we need to eliminate emissions from the global shipping industry by 2050. Our recent report identified hydrogen and ammonia as two alternative fuels that both have the potential to power shipping vessels while emitting zero greenhouse gases. However, when evaluated across their entire lifecycle of emissions (from extraction to end use), not all hydrogen is equal. Green hydrogen is the only option that can achieve the emissions reduction targets set forth in the Paris Agreement.

What is Green Hydrogen?

Green hydrogen uses renewable energy, such as solar and wind power, to electrolyze water, splitting water molecules into the components of hydrogen and oxygen. This production process emits zero carbon dioxide. The isolated hydrogen can then be used as a fuel. When used in a hydrogen fuel cell, the hydrogen fuel is electrochemically (without combustion) converted to electricity that can be used to power ships while emitting only water and heat as a byproduct.

Green hydrogen is currently the only established way to produce hydrogen without emitting GHG emissions or air pollution, making it a critical tool to help reach net zero by 2050. As we work to electrify everything that can feasibly plug into a clean power grid, green hydrogen is a promising zero-emission alternative fuel that can help sectors that lack a viable route to direct electrification, such as global shipping and heavy industry, transition to renewable energy.

When “Clean” Doesn’t Mean Green

The term “clean” hydrogen is misleading and promotes the false connotation that it is, in fact, clean. The fossil fuel industry has purposefully used this misleading terminology to continue to advocate for fossil fuel dependence in an attempt to save their polluting industry. “Clean” is not a label that should be given to any hydrogen that is produced from fossil fuels. The promotion of fossil fuel-based hydrogen will waste critical resources, time, and money by investing in stranded assets and dead-end infrastructure that cannot help us meaningfully tackle climate change.

Hydrogen fuels, such as grey, blue or brown, are produced from fossil fuels and continue to emit carbon dioxide into our atmosphere. Currently, the existing grey and brown hydrogen production methods emit the same amount of carbon dioxide as about one third of the European Union. Relying on carbon capture technologies to reduce the greenhouse gas emissions generated by the production of these types of hydrogen will require huge investments and the technology is not yet capable of completely capturing the released emissions.

Blue hydrogen, made from natural gas, is often referred to as “clean hydrogen” when it is paired with carbon capture technologies. However, the methane leakage throughout the lifecycle of blue hydrogen production is a significant cause for concern. Methane as a greenhouse gas is more potent than carbon dioxide and has more than 80 times the atmospheric warming power over a 20-year period. Even though CO2 has a longer-lasting effect, methane sets the pace for warming in the near term. Leaked methane emissions during blue hydrogen production are enough to cancel out any of the carbon dioxide emission reduction benefits gained from using hydrogen fuel in place of fossil fuels.

Another misleading argument to help retain our dependence on fossil fuels is the notion that hydrogen can be blended with natural gas and used in existing fossil fuel pipeline infrastructure with little consequence to the climate or environment. However, when hydrogen is burned like any other fossil fuel in a combustion engine or a furnace it produces nitrous oxide, which is an air pollutant that is toxic to people. Furthermore, hydrogen causes “embrittlement” to the existing fossil fuel pipeline infrastructure used to transport natural gas, weakening the metal or polyethylene pipes and further increasing the risks of leakage. Therefore, the blending of hydrogen fuel with fossil fuel, like natural gas, is not a solution to the climate crisis, and only serves to delay the urgently needed transition to a green hydrogen future.

Transitioning the Shipping Industry: The role of the US

Although the US does not have the largest maritime shipping fleet, it is the largest per capita consumer and the largest per capita emitter of greenhouse gases, and thus, bears a large responsibility to tackle fossil-fuel pollution from ships.

The U.S. government has committed to helping the shipping industry achieve zero emissions by 2050 and has taken up leadership on key global initiatives to adopt the use of zero-emission fuels. Building on these commitments, the US recently announced at the Our Ocean conference that it is charting a course to advance domestic and international green shipping corridors that “can spur early and rapid adoption of fuels and technologies that, on a lifecycle basis, deliver low- and zero-emissions across the maritime sector, placing the sector on a pathway to full decarbonization.” Green shipping corridors play an important role in advancing the early adoption of zero-emission fuels and technologies that are crucial next steps for the maritime industry to achieve the target of zero emissions no later than 2050.

Transitioning the shipping industry to zero-emission fuels, notably green hydrogen, needs to happen as rapidly as possible and will require both financial and strategic support from the U.S. government. The government must prioritize scaling up green hydrogen production as opposed to hydrogen derived from fossil fuels as part of the Department of Energy’s hydrogen program plan, increase its renewable energy production, and take advantage of the existing domestic and regional shipping routes that are already favorable for transitioning this decade.

This is an opportune moment for the Biden Administration to capitalize on international calls for the decarbonization of the shipping industry and national momentum for hydrogen fuel investments. The co-location of green hydrogen hubs with port facilities along green shipping corridors is an imperative next step to achieving the interconnected targets of global net-zero greenhouse gas emissions by no later than 2050, and zero greenhouse gas emissions from the international shipping sector by the same year. The US is well positioned to be a leader in the transition and at the forefront of aligning its fleet and energy system to zero-emission fuels, serving as an example for the international shipping industry to move away from dirty fossil fuels and towards truly clean alternative fuels, like green hydrogen.

For more resources on how the US can help transition the shipping industry, check out the ALL ABOARD: How the Biden-Harris Administration Can Help Ships Kick Fossil Fuels report.