Hydrogen’s role in expanding renewable energy in Texas

International Journal of Hydrogen Energy (2025), first author

Hydrogen systems
Where should electrolyzers, hydrogen storage and fuel cells be built in ERCOT, and how should hydrogen move between zones, to absorb surplus renewable generation and supply industrial hydrogen demand under uncertain 2030 renewable build-out?

First author

  • 8 ERCOT weather zones
  • 8,760 hours
  • 9 scenarios
  • Two-stage stochastic LP
  • Inter-zonal hydrogen pipelines

Research question

Where should electrolyzers, hydrogen storage and fuel cells be built in ERCOT, and how should hydrogen move between zones, to absorb surplus renewable generation and supply industrial hydrogen demand under uncertain 2030 renewable build-out?

Key insight

Dearer gas power diverted green hydrogen to power generation and raised emissions

When gas-fired backup power became much more expensive, the model built fuel cells and turned stored green hydrogen back into electricity. Industry then drew more hydrogen from gas reformers, and the round trip from power to hydrogen and back lost energy, so total emissions rose although gas-plant emissions fell.

How can dearer gas power raise emissions?

When gas-fired backup power becomes more expensive, the model starts to use stored green hydrogen in fuel cells to make electricity in hours of low wind and sun. That hydrogen no longer supplies industry, so gas reformers fill the gap with fossil hydrogen. Converting electricity to hydrogen and back loses energy, so in the paper's high-price cases total emissions rose even though emissions from gas plants fell.

Illustrative model with stylized numbers: it shows the mechanism described in the paper, not the study's data or results.

My contribution

First author. I did most of the work: the data pipeline from public ERCOT market disclosures, the stochastic planning model, the analysis and the writing.

How I approached it

  1. ChallengeThe model needed hourly wind and solar output for each of ERCOT's eight weather zones.

    What I didI built it from ERCOT's 60-day market disclosures: each wind and solar resource mapped to its county and zone, averaged to hours, gap-filled and summed, then turned into zone capacity factors.

    Why it matteredThe same capacity factors scaled planned capacity from the interconnection queue, so existing and future renewables shared one hourly basis.

  2. ChallengeHow much planned renewable capacity is built by 2030, and how fast demand grows, are both uncertain.

    What I didI formulated a two-stage stochastic program: hydrogen equipment is sized once, then operated hour by hour in nine scenarios combining three completion rates and three demand levels.

    Why it matteredThe sizes minimize expected cost over all nine scenarios instead of fitting a single forecast.

  3. ChallengeWind and solar output is concentrated far from electricity demand in the north and southeast, and from hydrogen demand on the Gulf Coast.

    What I didI added hydrogen pipelines between adjacent weather zones, with transport cost set by the distance between zone centres.

    Why it matteredThe model could then choose between making hydrogen near surplus power and moving it, or making it where it is used.

Design choices

Hold hydrogen demand fixed across scenarios
Alternatives considered: treating hydrogen demand as a third uncertain factorReliable hydrogen-demand data were lacking and computational cost mattered; the paper names this as future work.
Move hydrogen only by pipeline between neighbouring zones
Alternatives considered: adding truck or rail transportPipelines are the relevant mode for large-scale, long-term deployment; other modes were left out to keep the focus on supply and demand uncertainty.

Method

Two-stage stochastic linear program. The first stage sizes electrolyzers, hydrogen tanks and fuel cells in each of ERCOT's eight weather zones; the second stage schedules batteries, electrolysis, fuel cells, gas-fired backup, reformer hydrogen and inter-zonal hydrogen transport hour by hour over a full year, in nine scenarios (three electricity-demand levels by three completion rates of planned renewable capacity). Inputs are built from ERCOT 60-day SCED disclosures, the LBNL interconnection queue and EIA data.

Key findings

  1. Renewable (green) hydrogen covered only a few percent of industrial hydrogen demand; reformer hydrogen remained the main supply.
  2. Modest load flexibility (±5%) reduced CO₂ emissions from combined-cycle gas generation.

Boundary conditions

Inputs reflect 2022–2023 conditions; post-2023 federal hydrogen credit rules are not modeled.

What it led to

Next I asked the same flexibility question of firm low-carbon supply: whether hydrogen production can make existing nuclear plants more flexible and profitable. Hydrogen integration and policy support for U.S. nuclear power plants

Publications

  1. Int. J. Hydrogen Energy
    Hydrogen’s role in expanding renewable energy and reducing carbon emissions in Texas
    H. Li, J. Zhang
    International Journal of Hydrogen Energy, vol. 113, pp. 77–89, 2025.
    DOI Accepted manuscript (PDF) Code Cited by 9

Citation counts: Google Scholar, October 30, 2026.