Is Green Hydrogen Considered Renewable Energy?
Introducing Green Hydrogen
Green hydrogen is hydrogen that is produced through renewable energy sources, most commonly by using renewable electricity for electrolysis to split water into hydrogen and oxygen. This process of producing hydrogen is called electrolysis. According to the World Economic Forum, “Green hydrogen is made using renewables-powered electrolysis, while grey hydrogen is made from fossil fuels” (1).
Green hydrogen is considered a renewable energy because it is produced using renewable electricity from sources like solar, wind, hydropower or geothermal. As the International Renewable Energy Agency explains, “Hydrogen is considered ‘green’ when it is produced through the electrolysis of water powered by renewable electricity” (2). The ‘green’ refers to the renewable, low-carbon production process.
Interest and investment into green hydrogen has grown significantly in recent years. Many countries view green hydrogen as a promising way to decarbonize major sectors of the economy like transportation, manufacturing and heating. The International Energy Agency predicts that investments into electrolyzer capacity for green hydrogen production will exceed $40 billion by 2030 as adoption accelerates globally (3).
(1) https://www.weforum.org/agenda/2021/12/what-is-green-hydrogen-expert-explains-benefits/
(3) https://www.iea.org/reports/global-hydrogen-review-2021
Green Hydrogen vs Grey Hydrogen
Green hydrogen and grey hydrogen refer to two different production methods for hydrogen fuel. The key difference lies in how the hydrogen is produced:
- Grey hydrogen is produced from fossil fuels like natural gas or coal. The most common method is steam methane reforming, where high temperatures are used to split hydrogen from natural gas. This process generates significant carbon dioxide emissions.
- Green hydrogen, on the other hand, is produced using renewable electricity through a process called electrolysis. An electrolyzer splits water molecules into hydrogen and oxygen using renewable electricity like solar or wind power. This process generates no direct carbon emissions.
Green hydrogen is considered a renewable form of energy because its production relies on renewable power sources like solar and wind. The electrolysis process requires renewable electricity to split the water molecules. As long as the electricity comes from renewable sources, the resulting green hydrogen is also renewable and carbon-free.
Grey hydrogen, meanwhile, cannot be considered renewable since its production depends on fossil fuels. The steam methane reforming process emits carbon dioxide as a byproduct. Relying on finite resources like natural gas also makes grey hydrogen unsustainable in the long run. While grey hydrogen may serve as a transition fuel, green hydrogen is viewed as the most sustainable long-term option.
In summary, the key distinction is the energy sources and carbon emissions. Green hydrogen qualifies as renewable energy because it uses renewable electricity and does not create direct carbon emissions. Grey hydrogen relies on fossil fuels and generates significant emissions, making it non-renewable.
Green Hydrogen Production Methods
The main method for producing green hydrogen is through electrolysis powered by renewable energy sources like solar, wind, or hydro power. Electrolysis uses electricity to split water into its components of hydrogen and oxygen. When the electricity used in the process comes from renewable sources, the resulting hydrogen is considered “green”.
Solar and wind energy are commonly used to provide electricity for electrolysis. Solar photovoltaic panels or wind turbines generate electricity that can be directly fed into the electrolyzer to separate the water. Using renewable electricity ensures the full life cycle of the hydrogen fuel avoids fossil fuels and results in near-zero greenhouse gas emissions.[1]
Hydropower can also be utilized for electrolysis, though this is currently less common. The falling water in dams and reservoirs generates electricity that can split water via electrolysis, resulting in green hydrogen.
Other potential methods for green hydrogen production are still in early development, such as using biomass or biogas in specialized thermal chemical processes. However, water electrolysis powered by renewables is the primary scalable approach used today.
Benefits of Green Hydrogen
Green hydrogen offers several key benefits that make it an attractive renewable energy source. Firstly, when green hydrogen is produced and used, it results in zero carbon emissions. The production of green hydrogen via electrolysis uses renewable electricity like solar or wind power, and the combustion of hydrogen as a fuel emits only water vapor as a byproduct. This makes green hydrogen a truly carbon-free energy carrier (https://www.iberdrola.com/sustainability/green-hydrogen).
Secondly, green hydrogen provides a way to store and transport renewable energy over long distances and periods of time. The intermittent nature of renewables like solar and wind can make them difficult to integrate into the grid. However, by using excess renewable electricity to produce hydrogen via electrolysis, the energy can be stored as hydrogen fuel and then used or transported as needed (https://news.climate.columbia.edu/2021/01/07/need-green-hydrogen/).
Finally, green hydrogen has a wide range of potential applications as a fuel or feedstock. It can be used to power fuel cell vehicles, be blended into natural gas pipelines, provide high-temperature heat for industrial processes, and serve as a feedstock for the production of synthetic fuels and chemicals (https://www.acciona.com/green-hydrogen/). This versatility makes green hydrogen an attractive option across many sectors.
Challenges of Green Hydrogen
While green hydrogen shows great promise as a clean energy source, there are still significant challenges to its widespread adoption and use. Some of the main challenges include:
High costs currently – Producing green hydrogen is still expensive compared to fossil fuel-based hydrogen production. Electrolyzers to produce green hydrogen remain costly. According to 100%RE, green hydrogen production costs are up to 3-4 times higher than grey hydrogen from fossil fuels.
Scaling up production – To make green hydrogen competitive, production needs to be massively scaled up. The intermittent nature of renewables like solar and wind provides challenges to reliable and consistent green hydrogen production. More renewable energy capacity needs to be built to produce enough green hydrogen.
Building distribution infrastructure – New pipelines and transportation infrastructure is required to distribute green hydrogen. Retrofitting natural gas pipelines for hydrogen use also poses engineering challenges. Developing storage facilities and fuelling stations will be critical for adoption in industries and transportation.
Green Hydrogen Use Cases
Green hydrogen has many potential applications across several key sectors like transportation, electricity generation and storage, and industrial manufacturing. Some of the most promising use cases are:
Transportation:
Green hydrogen can be used to power fuel cell electric vehicles (FCEVs), like cars, trucks, buses, trains, ships and even airplanes. FCEVs combine hydrogen and oxygen to produce electricity to run the vehicle’s motor. Compared to traditional combustion engines, FCEVs have no tailpipe emissions – just water vapor. Green hydrogen’s high energy density makes it an ideal zero-emission fuel, especially for heavy vehicles traveling long distances.
Electricity Storage and Grid Balancing:
Green hydrogen offers a large-scale way to store renewable electricity from wind and solar. Electrolyzers can use excess renewable energy to split water and produce hydrogen, which can then be stored until needed. The hydrogen can be converted back into electricity via fuel cells when renewable supply is low. This grid balancing ability provides stability and helps address intermittency issues.
Industrial Applications:
Many industrial processes require hydrogen as an input. Green hydrogen can replace fossil fuel-based “grey” hydrogen currently used in refining, chemical & fertilizer production, metallurgy, electronics manufacturing, and more. This helps decarbonize heavy industry.
Green Hydrogen Adoption
The use of green hydrogen is still in the early stages, but is expected to grow significantly in the coming years. According to a PwC report, global demand for hydrogen could reach up to 500 million metric tons per year by 2050, driven by ambitious climate goals and hydrogen use in sectors like transportation, power generation, and industry.
The global green hydrogen market is projected to grow from USD 676 million in 2022 to USD 7.3 billion by 2027, representing a CAGR of 61%, according to MarketsandMarkets. Key factors driving growth include government policies, declining electrolyzer costs, and increasing use of hydrogen in sectors like chemicals, transportation, and power generation.
Many governments globally have introduced major policy initiatives and funding to accelerate green hydrogen production and use. For example, the European Union unveiled its Hydrogen Strategy in 2020, which aims to install 40 GW of renewable hydrogen electrolyzers by 2030. The U.S. Bipartisan Infrastructure Law provides over $8 billion in funding towards hydrogen hub development. Such policies and investments are expected to continue driving rapid growth.
Green Hydrogen vs Other Renewables
Green hydrogen provides many benefits compared to other renewable energy sources like solar, wind, and hydropower. A key advantage is that green hydrogen serves as an efficient storage medium for intermittent renewables. While solar and wind only produce energy when the sun is shining or wind is blowing, green hydrogen stores this energy so it can be used on demand.
Green hydrogen can also be more cost-effective and scalable than batteries for long-term energy storage. Battery storage works well for daily cycles, but is expensive for seasonal storage. Green hydrogen provides a more affordable way to stockpile renewables for extended periods. This enables broader deployment of renewables on the grid.
Additionally, green hydrogen can decarbonize sectors that are difficult to electrify, like heavy industry and long-haul transportation. While batteries work for light-duty vehicles, hydrogen fuel cells are better suited for ships, trains, and trucks. Green hydrogen provides a clean fuel source for high-temperature industrial processes that would otherwise rely on fossil fuels.
However, green hydrogen faces challenges like high production costs and the need for new infrastructure. The technology requires continued innovation to be cost-competitive with solar, wind, and other renewables. But in the long-term, green hydrogen is a critical complement to make 100% renewable energy systems achievable.
The Future of Green Hydrogen
Green hydrogen is poised to play a major role in the clean energy transition. As countries around the world aim to decarbonize their economies and reduce greenhouse gas emissions, green hydrogen offers a viable pathway for sectors that are difficult to electrify, like heavy industry and long-haul transportation. Some key factors that will determine the pace and scale of future green hydrogen adoption include:
Cost Reductions: Bringing down the cost of green hydrogen production will be critical. Renewable energy costs have fallen dramatically in recent years, making green hydrogen more cost competitive. Further reductions in electrolyzer costs and continued renewables cost declines can make green hydrogen even more attractive.
Supportive Policies: Government incentives and regulations to spur green hydrogen deployment, such as investment tax credits, carbon pricing, and hydrogen mandates, can help scale up production and create early markets. Many countries have announced major green hydrogen policy initiatives and roadmaps.
Infrastructure Development: Large-scale infrastructure like hydrogen pipelines, storage facilities, refueling stations, and port facilities will need to be built out to enable widescale utilization of green hydrogen across the energy system. Private-public partnerships can facilitate the high upfront capital costs.
Technology Advances: Improvements in electrolyzer tech, renewable energy integration, hydrogen storage, and fuel cell performance can optimize production processes and expand use applications. More efficient hydrogen end-use technologies will further drive adoption.
If key technical, economic and political hurdles are overcome, most forecasts predict green hydrogen playing a major role in decarbonization efforts by 2050, with some seeing it meeting up to 25% of global energy demand. Realizing green hydrogen’s full potential will require substantial investment and coordination across many sectors in the coming years.
Conclusion
In summary, green hydrogen is considered a renewable form of energy because it is produced through methods powered by renewable energy sources like solar, wind, hydroelectric, and geothermal. The key renewable attribute of green hydrogen is that it stores energy from intermittent renewable sources like solar and wind and provides that energy on demand in a usable hydrogen fuel form.
While green hydrogen faces challenges like high production costs today, rapid technology development and increasing adoption are helping overcome these hurdles. As more countries and companies announce plans and investments in green hydrogen, it is poised to play a major role in the global renewable energy transition.
With its ability to provide clean energy for hard-to-decarbonize sectors like heavy industry and long-term energy storage, green hydrogen can be considered a versatile renewable energy carrier and is an essential component of a sustainable energy future.
