What is green hydrogen?

Green hydrogen is defined based on carbon intensity thresholds.

The carbon intensity number may be different for different countries and organisations (kg CO2e/kg H2) as too are the system boundaries drawn to calculate carbon intensity (for example, production facility gate or including utilisation).

To help standardise the production of green hydrogen, various certification schemes have been developed. These schemes set the criteria for what constitutes green hydrogen while providing a framework for producers to follow. Some of the notable schemes include:

• International Partnership for Hydrogen and Fuel Cells in the Economy (IPHE) which provides a methodology and framework to calculate carbon intensity
• Australian Clean Energy Regulator Hydrogen Guarantee of Origin
• Green Hydrogen Organisation Green Hydrogen Standard
• UK Department of Business, Energy and Industrial Strategy Low Carbon Hydrogen Standard
• US Department of Energy Clean Hydrogen Production Standard

In the UK, a carbon intensity threshold of 2.4 kg CO2e/kg H2 qualifies as green hydrogen, while in Japan, it is hydrogen with a carbon intensity less than of 3.4 kg CO2/kg H2. In the US, there are different tiers of green hydrogen, with the highest tier specified at 4.0 kg CO2/kg H2.

The Future Made in Australia package includes a Hydrogen Production Tax Incentive (HPTI), with a stated carbon intensity threshold of 0.6 kg CO2e/kg H2 on a well-to-gate basis. This is an ambitious target, particularly in light of what qualifies as green hydrogen in other parts of the world.

One of the key aspects of green hydrogen production is the use of renewable energy sources. Hydrogen can be produced through electrolysis, where electricity is used to split water into hydrogen and oxygen.

For the hydrogen to be considered green, the electricity used in this process must come from renewable sources such as wind, solar or hydro power.

Depending on the jurisdiction, there are currently different guidelines for power “matching”, that is, when the power was generated compared to when it was used to produce hydrogen. For hourly matching, the project must demonstrate that the power was generated in the same hour the electrolyser consumed it, and within an allowed geographic region. Other types of matching include monthly and annual matching, both of which are considerably less expensive to implement than hourly matching.

At present, there is no prescription for hourly matching in Australia, however, in the EU and for sellers to the EU, hourly matching will be required from 2030. Hourly matching pushes projects toward co-located renewables and batteries for storage, flexible electrolyser operation or Power Purchase Agreement (PPA) stacks with diverse profiles to cover each hour, all of which drives up power costs and project complexity.

The integration of green hydrogen with renewable energy sources such as solar, wind and pumped hydro is emerging as a cornerstone of decarbonisation strategies across the energy and water sectors.

The use of various technologies has enabled projects to transition to cleaner energy systems with hydrogen positioned as a key element in future energy strategies. GHD’s involvement in Australia’s renewable energy sector also outlines emerging storage solutions such as pumped hydro, flywheels, lithium-ion, lead-acid and flow batteries.

Our involvement spans the study and development of renewable energy and storage initiatives, including over 30 projects of 4 GW / 6 GWh of utility-scale battery energy storage systems (BESS), 10.5 GW of wind energy and 3.3 GW of solar power. These figures reflect a substantial commitment to advancing sustainable energy infrastructure and demonstrate our deep experience in integrating diverse technologies to meet Australia’s growing energy needs.

GHD has been actively involved in the development of global hydrogen strategies. Our work spans across various national and international frameworks, contributing to the advancement of green hydrogen production and certification.

Some of our notable contributions include:

• Australia’s Hydrogen Guarantee of Origin (GO) Scheme: We helped the Department of Climate Change, Energy, the Environment and Water (DCCEEW) to define what could qualify as green hydrogen, identify hydrogen production pathways and recommended boundaries for carbon intensity calculations, based on accepted methodologies elsewhere in the world, adapted for Australian conditions.
• UAE’s National Hydrogen Strategy: Our team worked with the Ministry of Energy and Infrastructure to develop the UAE national hydrogen strategy.
• Canada’s H2GO Report: We contributed to the authorship of the H2GO Canada report, developing sustainable approaches to hydrogen development in Canada.

We’re proud to be part of the global shift towards safe, reliable and affordable clean energy and committed to supporting our clients in building a more sustainable and resilient energy future.

Learn more about green hydrogen and its potential applications in Green Hydrogen: A Desert Full of Possibilities.