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arxiv: 2606.13215 · v1 · pith:D2ARTMR7new · submitted 2026-06-11 · 📡 eess.SY · cs.CE· cs.SY

Mitigating business risks from renewable PPA power sourcing uncertainties for European green hydrogen production: Robust system design, regulatory adjustments and offtake flexibility

Jonathan Brandt , Astrid Bensmann , Richard Hanke-Rauschenbach This is my paper

Pith reviewed 2026-06-27 06:03 UTC · model grok-4.3

classification 📡 eess.SY cs.CEcs.SY
keywords green hydrogenpower purchase agreementadditionalitytemporal correlationelectrolyseremission intensityofftake agreementEuropean bidding zones
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The pith

Relaxing temporal correlation rules for renewable PPAs enables green hydrogen producers to fulfill offtake agreements without exceeding emission thresholds.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper investigates the business risks that strict EU renewable power sourcing rules pose to green hydrogen production projects. By modeling electrolyser operations under additionality and temporal correlation requirements across European bidding zones, it demonstrates that PPA and storage upsizing can mitigate risks but at higher costs. In contrast, relaxing temporal correlation combined with greater offtake flexibility improves system robustness and simultaneously lowers production costs. The key finding is that these relaxed rules do not lead to emission intensity thresholds being exceeded, supporting the case for regulatory adjustments to aid project ramp-up.

Core claim

Applying different design paradigms to a green hydrogen production system reveals that electrolyser operator measures, such as PPA and storage upsizing, can help to mitigate the business risks posed by the additionality criterion but come with increased costs. Alternatively, relaxed temporal correlation and increased offtake flexibility both increase production system robustness and reduce production costs simultaneously. Whereby relaxing temporal correlation rules does not result in exceeded emission intensity thresholds, underlining the potential of extended transitional rules to support the ramp-up of European green hydrogen production.

What carries the argument

Modeling of green hydrogen production systems under varying constraints from power purchase agreements, including additionality and temporal correlation criteria, with evaluations of storage, offtake flexibility, and emission intensity across different European bidding zones.

If this is right

  • Electrolyser operators facing additionality rules can use PPA and storage upsizing to reduce risks of missing offtake agreements, though this increases costs.
  • Relaxed temporal correlation rules enhance production system robustness while reducing costs.
  • Increased offtake flexibility also contributes to lower production costs and greater robustness.
  • Relaxing temporal correlation does not cause emission intensity thresholds to be exceeded in the modeled scenarios.
  • Regulatory review of power sourcing rules could accelerate the ramp-up of green hydrogen production in Europe.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Similar modeling approaches might be useful for assessing risks in other renewable-based fuel productions.
  • Zone-specific differences in bidding zones suggest tailored regulatory approaches could be beneficial.
  • Extending these findings to real-world pilot projects could validate the cost savings under relaxed rules.
  • The interaction between additionality and temporal correlation may have parallels in other energy policy areas like renewable certificates.

Load-bearing premise

The computer models of different production system designs accurately represent real-world interactions between PPA constraints, storage operation, offtake contracts, and emission calculations across European bidding zones.

What would settle it

Comparing modeled emission intensities against measured values from operating green hydrogen facilities that use relaxed temporal correlation rules in various European bidding zones.

Figures

Figures reproduced from arXiv: 2606.13215 by Astrid Bensmann, Jonathan Brandt, Richard Hanke-Rauschenbach.

Figure 1
Figure 1. Figure 1: Set-up of the modelled green hydrogen production [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Analysed design paradigms of green hydrogen producti [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Optimisation results for the standard configuration [PITH_FULL_IMAGE:figures/full_fig_p008_3.png] view at source ↗
Figure 5
Figure 5. Figure 5: Comparison of optimisation results between the standard [PITH_FULL_IMAGE:figures/full_fig_p011_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Comparison of optimisation results between the standard [PITH_FULL_IMAGE:figures/full_fig_p013_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Comparison of optimisation results between the standard [PITH_FULL_IMAGE:figures/full_fig_p014_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Optimisation results for the modified green hydrogen [PITH_FULL_IMAGE:figures/full_fig_p016_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: Comparison of optimisation results between the standard [PITH_FULL_IMAGE:figures/full_fig_p018_9.png] view at source ↗
read the original abstract

As energy prices surge for the second time in recent years driven by the ongoing crisis in the Middle East, the European Union's continuing reliance on fossil energy imports is becoming increasingly apparent. However, despite offering an intriguing prospect of improved energy resilience, the ramp-up of local green hydrogen production lags far behind the officially stated ambitions set after the 2022 energy crisis. A prominent reason for the widening implementation gap between announced and realised production projects is overly strict rules on renewable power sourcing, prompting Member states' ministries and the European Commission to propose advancing a planned rules review from 2028 to 2026. To contribute to a successful review and rule adjustments, we address an important gap in understanding the effects of power purchase rules on green hydrogen production. By taking the perspective of European electrolyser operators, we show how the criterion of additionality and its interaction with required temporal correlation can jeopardise the fulfilment of green hydrogen offtake agreements and affect green hydrogen production costs across different European bidding zones. Applying different design paradigms to a green hydrogen production system reveals that electrolyser operator measures, such as PPA and storage upsizing, can help to mitigate the business risks posed by the additionality criterion but come with increased costs. Alternatively, relaxed temporal correlation and increased offtake flexibility both increase production system robustness and reduce production costs simultaneously. Whereby relaxing temporal correlation rules does not result in exceeded emission intensity thresholds, underlining the potential of extended transitional rules to support the ramp-up of European green hydrogen production.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The manuscript analyzes the effects of EU renewable power sourcing rules (additionality and temporal correlation) on green hydrogen production from the electrolyser operator perspective. It models multiple production system designs incorporating PPAs, storage, and offtake contracts across European bidding zones, concluding that PPA/storage upsizing mitigates risks at higher cost while relaxed temporal correlation and greater offtake flexibility simultaneously lower costs and increase robustness without exceeding emission intensity thresholds.

Significance. If the simulation results are robust, the work supplies quantitative evidence that could support advancing the 2026 review of sourcing rules to accelerate green hydrogen deployment. The multi-paradigm design approach for assessing business risks from PPA uncertainties is a constructive framing, though its policy relevance hinges on model fidelity to real grid and emission dynamics.

major comments (2)
  1. [Modeling and Results sections] The central claim that relaxing temporal correlation does not result in exceeded emission intensity thresholds (abstract and results) depends on the internal representation of PPA constraints, storage dispatch, offtake flexibility, and bidding-zone grid mixes. No validation against real dispatch data, comparison to marginal vs. average emission factors, or sensitivity analysis is described, making the finding potentially sensitive to untested modeling choices rather than a general property of the rules.
  2. [Methods and Case Study sections] The production-system simulations are presented without disclosed input data, parameter sources, or cross-validation to actual European bidding-zone operations, which is load-bearing for the quantitative cost and robustness comparisons across design paradigms.
minor comments (2)
  1. [Abstract] The abstract would benefit from naming the specific bidding zones modeled and reporting the magnitude of cost or robustness changes (e.g., percentage reductions).
  2. [Introduction and Methods] Notation for emission intensity thresholds and temporal correlation windows should be defined consistently when first introduced.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback highlighting areas where additional transparency and robustness checks would strengthen the manuscript. We address each major comment below and commit to revisions that directly respond to the concerns raised.

read point-by-point responses

  1. Referee: [Modeling and Results sections] The central claim that relaxing temporal correlation does not result in exceeded emission intensity thresholds (abstract and results) depends on the internal representation of PPA constraints, storage dispatch, offtake flexibility, and bidding-zone grid mixes. No validation against real dispatch data, comparison to marginal vs. average emission factors, or sensitivity analysis is described, making the finding potentially sensitive to untested modeling choices rather than a general property of the rules.

    Authors: We agree that the emission-intensity results would be more convincing with explicit sensitivity testing and validation steps. In the revised manuscript we will add a new subsection under Results that (i) compares average versus marginal emission factors for the bidding zones studied, (ii) reports a one-at-a-time sensitivity analysis on key parameters (storage efficiency, PPA matching tolerance, offtake flexibility), and (iii) benchmarks selected dispatch outcomes against publicly available ENTSO-E and national grid data for the same zones and years. These additions will clarify the range of conditions under which the central claim holds. revision: yes

  2. Referee: [Methods and Case Study sections] The production-system simulations are presented without disclosed input data, parameter sources, or cross-validation to actual European bidding-zone operations, which is load-bearing for the quantitative cost and robustness comparisons across design paradigms.

    Authors: We accept that full reproducibility requires explicit data disclosure. The revised Methods section will be expanded with a new table listing every input parameter, its source (literature, public databases, or assumption), and the exact values used. We will also deposit the complete input data sets, model code, and output files in a public repository (Zenodo) and reference it in the manuscript. Where possible we will add a short cross-validation paragraph comparing simulated annual production volumes and cost ranges to reported figures from operating European electrolyser projects. revision: yes

Circularity Check

0 steps flagged

No significant circularity in simulation-based assessment of PPA rules

full rationale

The paper's central claims rest on computational simulations of electrolyser systems under varying PPA, storage, and offtake constraints across bidding zones. These produce direct outputs for costs and emission intensities when temporal correlation is relaxed. No load-bearing steps reduce by construction to fitted parameters renamed as predictions, self-definitional criteria, or self-citation chains; the emission threshold result follows from the modeled dispatch and grid-mix assumptions rather than tautological re-expression of inputs. The derivation is therefore self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Only the abstract is available, so specific free parameters (such as any fitted storage capacities, PPA multipliers, or cost coefficients), axioms (such as assumptions on bidding zone price behavior or emission factors), and invented entities cannot be identified. The paper likely relies on standard energy systems modeling assumptions not detailed here.

pith-pipeline@v0.9.1-grok · 5823 in / 1136 out tokens · 29085 ms · 2026-06-27T06:03:25.972217+00:00 · methodology

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Reference graph

Works this paper leans on

18 extracted references · 5 canonical work pages

  1. [1]

    Stromgestehungskosten Erneuerbare Energien,

    I. Fraunhofer et al., “Stromgestehungskosten Erneuerbare Energien,” Fraunhofer- Institut für solare Energiesysteme ISE, no. Juli, p. 45, 2024, [Online]. Available: https://www.ise.fraunhofer.de/de/veroeffentlichungen/studien/studie- stromgestehungskosten-erneuerbare-energien.html

    2024

  2. [2]

    Electricity prices components for non-household consumers - annual data (from 2007 onwards),

    Eurostat, “Electricity prices components for non-household consumers - annual data (from 2007 onwards),” 2026, [Online]. Available: https://ec.europa.eu/eurostat/databrowser/view/nrg_pc_205_c__custom_20996616/de fault/table

    2007

  3. [3]

    Greenhouse gas emission intensity of electricity generation in Europe,

    European Environment Agency, “Greenhouse gas emission intensity of electricity generation in Europe,” 2026, [Online]. Available: https://www.eea.europa.eu/en/analysis/indicators/greenhouse-gas-emission-intensity- of-1?activeAccordion=546a7c35-9188-4d23-94ee-005d97c26f2b

    2026

  4. [4]

    Cost and competitiveness of green hydrogen and the effects of the European Union regulatory framework,

    J. Brandt et al., “Cost and competitiveness of green hydrogen and the effects of the European Union regulatory framework,” Nat. Energy, vol. 9, no. June, pp. 703–713, 2024, doi: 10.1038/s41560-024-01511-z

    work page doi:10.1038/s41560-024-01511-z 2024

  5. [5]

    Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp,

    I. H. Bell, J. Wronski, S. Quoilin, and V. Lemort, “Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp,” Ind. \& Eng. Chem. Res., vol. 53, no. 6, pp. 2498–2508, 2014, doi: 10.1021/ie4033999

    work page doi:10.1021/ie4033999 2014

  6. [6]

    H. D. Baehr and S. Kabelac, Thermodynamik. Hannover: Springer Vieweg Berlin, Heidelberg, 2016

    2016

  7. [7]

    Energetic evaluation of high pressure PEM electrolyzer systems for intermediate storage of renewable energies,

    B. Bensmann, R. Hanke-Rauschenbach, I. K. Peña Arias, and K. Sundmacher , “Energetic evaluation of high pressure PEM electrolyzer systems for intermediate storage of renewable energies,” Electrochim. Acta, vol. 110, pp. 570–580, 2013, doi: 10.1016/j.electacta.2013.05.102

    work page doi:10.1016/j.electacta.2013.05.102 2013

  8. [8]

    Produkt und Preisinformation für den Zugang zu dem von der RWE Gas Storage West GmbH (RGSWest) betriebenen Gasspeicher,

    RWE AG, “Produkt und Preisinformation für den Zugang zu dem von der RWE Gas Storage West GmbH (RGSWest) betriebenen Gasspeicher,” pp. 1–9, 2023, [Online]. Available: https://www.rwe-gasstorage-west.com/-/media/RWE/RWE-Gas- Speicher/documents/produkte-preise-agb/produkt-und-preisinformationen.pdf

    2023

  9. [9]

    renewables.ninja,

    I. Staffell and S. Pfenninger, “renewables.ninja,” 2025. https://www.renewables.ninja/

    2025

  10. [10]

    Using bias-corrected reanalysis to simulate current and future wind power output,

    I. Staffell and S. Pfenninger, “Using bias-corrected reanalysis to simulate current and future wind power output,” Energy, vol. 114, pp. 1224–1239, 2016, doi: 10.1016/j.energy.2016.08.068

    work page doi:10.1016/j.energy.2016.08.068 2016

  11. [11]

    Long-term patterns of European PV output using 30 years of validated hourly reanalysis and satellite data,

    S. Pfenninger and I. Staffell, “Long-term patterns of European PV output using 30 years of validated hourly reanalysis and satellite data,” Energy, vol. 114, pp. 1251– 1265, 2016, doi: 10.1016/j.energy.2016.08.060

    work page doi:10.1016/j.energy.2016.08.060 2016

  12. [12]

    Germany’s offshore wind capacity factors - Energy Numbers

    A. Z. Smith, “Germany’s offshore wind capacity factors - Energy Numbers.” https://energynumbers.info/germanys-offshore-wind-capacity-factors

  13. [13]

    Wind energy in Europe - 2024 Statistics and the outlook for 2025- 2030,

    Wind Europe, “Wind energy in Europe - 2024 Statistics and the outlook for 2025- 2030,” 2025. [Online]. Available: https://windeurope.org/data/products/wind-energy-in- europe-2024-statistics-and-the-outlook-for-2025-2030/

    2024

  14. [14]

    Solarpark Langenenslingen-Wilflingen - Das erste Solargroßprojekt in Baden- Württemberg

    EnBW, “Solarpark Langenenslingen-Wilflingen - Das erste Solargroßprojekt in Baden- Württemberg.” https://www.enbw.com/unternehmen/themen/solarenergie/solarpark- langenenslingen-wilflingen/ (accessed May 01, 2026). 13

    2026

  15. [15]

    iea wind - Report 2023 Spain,

    I. Cruz and L. Arribas, “iea wind - Report 2023 Spain,” 2024. [Online]. Available: https://iea-wind.org/wp-content/uploads/2024/11/Spain_2023.pdf

    2023

  16. [16]

    TotalEnergies starts its largest European solar project

    A. Hernandez and Reu ters, “TotalEnergies starts its largest European solar project.” https://www.reuters.com/sustainability/climate-energy/totalenergies-starts-its-largest- european-solar-project-2025-05-22/ (accessed May 01, 2026)

    2025

  17. [17]

    Electricity prices for non-household consumers,

    eurostat, “Electricity prices for non-household consumers,” 2024. https://ec.europa.eu/eurostat/databrowser/view/nrg_pc_205/default/table?lang=en

    2024

  18. [18]

    COMMISSION DELEGATED REGULATION (EU) 2023/1184,

    European Commission, “COMMISSION DELEGATED REGULATION (EU) 2023/1184,” 2023. https://eur-lex.europa.eu/legal- content/EN/TXT/?uri=uriserv%3AOJ.L_.2023.157.01.0011.01.ENG&toc=OJ%3AL%3A 2023%3A157%3ATOC

    2023