Catalyst: Strategic – New Zealand-Germany Green Hydrogen Research Programme

Green hydrogen can be produced through the electrolysis of water. As this process uses electricity, minimising the energy input is critical. Currently proton exchange water electrolysers represent the state-of-the-art technology, but this technology is very expensive due to use of noble metals and expensive fluorinated ion-exchange membranes. Newly developed Anion Exchange Membrane Electrolysers would drastically reduce electrolysis costs (inexpensive and abundant materials, low-cost membranes) but currently these systems have the lowest hydrogen production rates of all water electrolysis technologies and suffer from efficiency.

In this project we will produce new electrodes which will increase the hydrogen production rates (lower CAPEX) and improvement hydrogen production efficiency (lower OPEX). We can achieve this through the combined expertise of the NZ and German teams, who together have experience working with advanced catalytic materials, water electrolysis design and construction, and cutting-edge materials analysis.

Ultimately we will construct and demonstrate the first Anion Exchange Membrane Electrolyser stack in New Zealand and show that this can meet the 2030 performance target set by Hydrogen Europe.

About 99% of current global hydrogen production is ‘brown’ hydrogen, which is formed from fossil fuels and leads to associated CO2 emissions.  In contrast, ‘green’ hydrogen is produced from water, via electrolysis using renewable electricity. When burnt it forms only energy and water, so green hydrogen is a carbon-zero fuel (energy carrier). Addressing global climate change requires urgent implementation of decarbonisation initiatives, so green hydrogen has an important role to play.

Green hydrogen will become a key vector to carry and store renewable energy. But whilst hydrogen has a high gravimetric energy density, its volumetric density is very low, making it a challenge to store. At present, hydrogen is stored either by compressing it to high pressure (700 bar) or by liquification through cryogenic cooling. Neither are appropriate for large-scale long-term storage due to system leakage losses, safety concerns, mass and cost.

This joint research program supports New Zealand’s and Germany's transformation into a green hydrogen economy by targeting the development of a commercially viable hydrogen storage technology, which will enable wide-spread uptake of new hydrogen technologies by various sectors, including electricity, transportation and industry. These project outcomes are intrinsically linked to, and aligned with, the Māori worldview of kaitiakitanga.

We will develop safe, large scale, long term hydrogen storage using TiFe metal alloys. New synthetic methods will be developed, from fundamental research studies, to produce novel cubic-TiFe materials with outstanding hydrogen uptake characteristics and cycling durability. Using state-of-the-art theoretical models, we will build new understanding of the atomic level mechanisms that govern hydrogen absorption and desorption by these materials, enabling ‘smart design’ of new cubic-TiFe materials with unprecedented hydrogen storage performance, produced from low-cost raw materials.

This research collaboration leverages world-leading expertise and experience from both New Zealand and Germany. The New Zealand team includes experts in chemistry, materials, and engineering from the University of Otago, Victoria University of Wellington, University of Auckland, University of Canterbury and Unitec. The German team are drawn from the internationally-renowned Institute of Hydrogen Technology at Helmholtz-Zentrum Hereon (HZH).

Our bilateral collaboration targets an essential enabling technology for New Zealand’s transition to a hydrogen economy, by addressing issues of commercial viability and scalability of large-scale, high-capacity, long-lifetime, low-cost hydrogen storage technology. This will enable the storage, transport and buffered distribution of hydrogen produced from renewable energy, thus enabling the decarbonisation of New Zealand’s energy, industry and transport sectors, whilst simultaneously improving our energy resilience and independence.

Aotearoa New Zealand has committed to a net-zero carbon economy by 2050. However, the transformation pathways for our energy systems remain unclear. Green hydrogen technologies, by offering long-term storage and green fuels, are a potential enabler for a net-zero emissions energy sector.

The government has already taken an important first step by laying out a hydrogen roadmap. However, quantifying the role of hydrogen and evaluating it from an integrated standpoint, including co-benefits, environmental impacts, uncertainties, cost-competitiveness, and its role for an integrated energy system, remain unaddressed. This is what we aim to do in this project.

We will develop the most comprehensive integrated energy system model for New Zealand. It will be open source and adaptable for use in many future studies. We will do this by building on the energy system planning tool REMix from our partners of the German Aerospace Center, and by developing machine-learning approaches for forecasting transport demand and detecting potential applications of hydrogen. 

We will be able to answer the following pressing questions related to the energy transformation:

• Can green hydrogen help achieve zero-carbon transport, both in and outside cities?
• Can green hydrogen in urban systems help to fulfil net-zero carbon goals? And how does hydrogen help industries, including the primary sector?
• How does green hydrogen aid the integration of renewables? And what are optimal levels of hydrogen deployment for minimizing spillage? 
• How can the uncertainties from extreme droughts and future hydrogen costs be addressed in planning tools?
• Can hydrogen provide competitive long-term storage (like a “national battery”)?
• What are the environmental impacts and benefits of hydrogen, contextualized in an integrated energy system?
• What are the opportunities that green hydrogen opens to our local communities? Can it improve energy poverty and equity?
• What is New Zealand’s potential role within the hydrogen exporting triangle (Australia, Chile, North America)? And what hydrogen concepts should New Zealand envision? For example, off-shore hydrogen hubs with pipelines and ship transport? Production close to consumers? Hydrology-dependent  imports and exports?
• Can New Zealand become energy independent by using hydrogen technologies? And can we power the Pacific Islands?

We will leverage the existing hydrogen roadmap and the expertise of an international, multidisciplinary team of energy, transport, electricity, and environmental experts to assess the role, advantages, and benefits of future hydrogen use in Aotearoa. 

We will disseminate our work with the government, industry and Māori partners, and other scientists through workshops, conferences, and publications.