University of Auckland's Groundbreaking Modelling on Green Hydrogen

New research from the University of Auckland reveals that green hydrogen, produced through electrolysis using renewable electricity, will likely play only a limited role in reducing New Zealand's industrial emissions before 2050. Led by Master's student Geordie Reid from the Business School, the study uses advanced bottom-up modeling to assess pathways for decarbonising industrial process heat—a major emissions source in sectors like cement production, steel manufacturing, and chemical processing. Published in the journal Sustainability, this MBIE-funded work underscores electrification as the primary solution, positioning green hydrogen as a complementary option at best.

The findings challenge overly optimistic views on hydrogen's immediate impact, highlighting economic realities in Aotearoa New Zealand's push toward net-zero emissions by 2050. As the country grapples with hard-to-abate industrial processes, this research from UoA provides critical insights for policymakers, industry leaders, and researchers exploring sustainable energy careers.

🛠️ New Zealand's Industrial Emissions Landscape

New Zealand's industrial sector is the second-largest contributor to greenhouse gas emissions after transport, with process heat accounting for over 75% of industrial energy use—around 165 PJ annually based on 2019 data, though total industrial energy dipped to 150 PJ in 2024 amid economic shifts. Fossil fuels dominate, with coal and natural gas fueling high-temperature applications (>300°C) in cement and lime kilns (non-metallic minerals), natural gas reforming for methanol and ammonia (petrochemicals/chemicals), and coal reduction in ironsand steelmaking (primary metals). Food and beverage manufacturing, including dairy drying, contributes significantly to lower-temperature heat needs.

Emissions from these processes are stubborn: coal use held at 15 PJ in industry in 2024, while gas fell but remains key. With net-zero targets under the Climate Change Response Act, excluding biogenic methane, industry must slash emissions through the 2022-2035 budgets. The UoA study zooms in on process heat decarbonisation, where direct electrification faces technical hurdles at extreme temperatures, sparking interest in green hydrogen.

The TIMES Model: A Sophisticated Approach to Forecasting

The research employs the TIMES (The Integrated MARKAL-EFOM System) model, a least-cost optimization tool tailored for New Zealand (NZIES instance), simulating 2019-2050 pathways in five-year steps across 96 time slices for seasonal and diurnal variations. Heat demands are disaggregated by temperature bands—low (<100°C), intermediate (100-300°C), high (>300°C)—and delivery modes (boilers vs. direct furnaces/kilns), drawing from EECA's End-Use Demand database and MBIE balances.

• Technologies modeled: Electrode boilers and heat pumps for electrification; biomass/geothermal boilers; green hydrogen via PEM electrolysis, combustion boilers, furnaces, and kilns.
• Scenarios: Eight combinations testing 'steady progress' vs. 'rapid development' in electrolyser CAPEX (NZD 1404/kW to 882 steady; 716 to 299 rapid by 2050), efficiencies (72-82% steady; 80-88% rapid), and end-use costs.
• Assumptions: Carbon price rising to NZD 250/t by 2050; plant closures (e.g., Tiwai smelter 2024); grid constraints approximated.

This granular approach reveals trade-offs, prioritizing system-wide cost minimization over siloed tech optimism.

Key Projections: Minimal Green Hydrogen Uptake by 2050

In six of eight scenarios, green hydrogen uptake is zero by 2050, with electrification phasing out coal by 2040 and gas by 2050. Only 'rapid development' cases (Scenarios 6 and 8) show 5.7-12.4% of process heat from hydrogen—exclusively high-temperature direct heat post-2040, totaling 6.7-14.6 PJ. Biomass use declines to ~33 PJ, geothermal persists for low-heat.

Full decarbonisation occurs regardless, but hydrogen's niche is narrow: primary metals and mineral products where electrification falters. For context, this caps hydrogen at ~12% even under best-case tech leaps, far below some Hydrogen Roadmap visions of 8% total energy share.

Cost and Efficiency: Why Green Hydrogen Struggles

High upfront costs plague green hydrogen: electrolyser CAPEX remains elevated, even dropping to NZD 299/kW in optimistic paths, yielding levelized costs uncompetitive with electricity at NZD 50-100/MWh. Efficiency losses compound issues—~20-30% round-trip from electricity to heat via electrolysis, storage, and combustion—versus near-100% for direct electric boilers.

Global projections align: IRENA sees LCOH below USD 2/kg possible by 2030 with scale, but NZ's small market lags. Carbon pricing (to NZD 250/t) helps, but grid peaks favor electrification unless constraints bind tightly.

Photo by Mathew Waters on Unsplash

Optimistic Horizons: Post-2050 Promise and Exports

If rapid declines materialize—cheaper wind/solar, scaled electrolysis sans rare metals, infrastructure standards—hydrogen could expand post-2050 for exports. NZ's 80%+ renewable grid offers a low-emissions edge; projects like Kapuni (5MW electrolyser, FID Feb 2026) signal momentum for fertilizer decarbonisation. Lead author Le Wen notes export potential to Asia, complementing domestic limits.

For researchers eyeing research jobs in energy modeling, UoA's work exemplifies demand for TIMES expertise.

Insights from UoA Researchers

Geordie Reid emphasizes process heat's toughness: "One of the toughest elements... is decarbonising industrial process heat." Selena Sheng details losses: "Hydrogen technologies exhibit lower overall efficiency..." Basil Sharp urges policy: "Remove barriers like absence of industrial standards." Le Wen highlights advantages: "NZ is well placed... could give a strong new export opportunity."

These voices from UoA's Business School and Energy Centre reflect interdisciplinary prowess, attracting talent via higher ed jobs in sustainable economics.

Current Green Hydrogen Initiatives in NZ

Despite limits, momentum builds: Hiringa Energy's Kapuni project (Feb 2026 FID) pairs wind with 5MW electrolysis for Ballance's fertilizer plant, cutting ~12kt CO2/year.Kapuni details. MBIE's Hydrogen Action Plan (2024) eyes hard-to-abate roles, with GNS tracking ecosystem growth.

• Potential: Urban PV surplus for electrolysis in Auckland, Wellington.
• Challenges: Infrastructure lags, competing with electrification pilots in dairy.

Promising Alternatives to Green Hydrogen

Electrification leads: Heat pumps for low-temp (food drying), electrode boilers for medium; biomass (wood residues, 17-33 PJ sustainable) and geothermal for specifics. Natural hydrogen exploration leverages NZ geology for cheaper supply. Efficiency gains and biofuels fill gaps; Tiwai closure eases electricity strain.

For career advice on green tech transitions, see academic CV tips.

Policy Implications and Recommendations

Prioritize electrification funding (e.g., GIDI), target H2 subsidies for high-temp niches (metals, cement). Develop standards for transport/storage; reinforce grids. UoA urges balanced investment, avoiding over-reliance on nascent H2.

Photo by Josh Tere on Unsplash

Future Outlook and UoA's Pivotal Role

Post-2050, scaled H2 could export, but 2050 hinges on electrification. UoA leads with NZIES modeling, fostering PhDs and postdocs—explore postdoc opportunities, rate professors, or university jobs in NZ. As net-zero looms, such research drives actionable science.

Check NZ academic jobs for energy roles.