Flexible dispatch strategy for electric grid integrating PEM electrolyzer for hydrogen generation

Abstract

Proton exchange membrane (PEM) electrolyzer (EL) is regarded as a promising technology for hydrogen generation, offering load flexibility for electric grids (EGs), especially those with a high penetration of renewable energy (RE) sources. This paper proposes a PEM-focused economic dispatch strategy for EG integrated with wind-electrolysis systems. Existing strategies commonly assume a constant efficiency coefficient to model the EL, while the proposed strategy incorporates a bottom-up PEM EL model characterized by a part-load efficiency curve, which accurately represents the nonlinear hydrogen production performance, capturing efficiency variations at different loads. To model this, it first establishes a 0D electrochemical model to derive the polarization curve. Next, it accounts for the hydrogen and oxygen crossover phenomena, represented by the Faraday efficiency, to correct the stack efficiency curve. Finally, it includes the power consumption of ancillary equipment to obtain the nonlinear part-load system efficiency. This strategy is validated using the PJM-5 bus test system with coal-fired generators (CFGs) and is compared with a simple EL model using constant efficiency under three scenarios. The results show that the EL modeling method significantly influences both the dispatch outcome and the economic performance. Sensitivity analyses on coal and hydrogen prices indicate that, for this case study, the proposed strategy is economically advantageous when the coal price is below 121.6 $/tonne. Additionally, the difference in total annual operating cost between using the efficiency curve anda constant efficiency to model becomes apparent when the hydrogen price ranges from 2.9 to 5.4 $/kg.

Graphical abstract

Keywords

proton exchange membrane electrolyzer (PEM EL) / nonlinear part-load efficiency / optimal dispatch strategy / hydrogen / wind energy

References

[1] InternationalEnergy Agency. Net zero by 2050: A roadmap for the global energy sector. 2021, available at IEA website

[2] Satyapal S, Rustagi N, Green T, et al. U.S. national clean hydrogen strategy and roadmap. 2023, available at US Department of Energy website

[3] Andrenacci S, Choi Y, Raka Y, et al. Haeolus project, deliverable number 4.4 electrolysers towards EU MAWP 2023 targets and beyond. 2022

[4] Patonia A, Poudineh R. Cost competitive green hydrogen: How to lower the cost of electrolysers? 2022, available at the Oxford Institute for Energy Studies website

[5] Belderbos A , Valkaert T , Bruninx K . . Facilitating renewables and power-to-gas via integrated electrical power-gas system scheduling. Applied Energy, 2020, 275: 115082

[6] Xu X , Hu W , Liu W . . Risk-based scheduling of an off-grid hybrid electricity/hydrogen/gas/ refueling station powered by renewable energy. Journal of Cleaner Production, 2021, 315: 128155

[7] Clegg S , Mancarella P . Integrated modeling and assessment of the operational impact of Power-to-Gas (P2G) on electrical and gas transmission networks. IEEE Transactions on Sustainable Energy, 2015, 6(4): 1234–1244

[8] Zuo F , Zhang Y , Zhao Q . . Two-stage stochastic optimization for operation scheduling and capacity allocation of integrated energy production unit considering supply and demand uncertainty. Proceedings of CSEE, 2022, 42(22): 8205–8215 (in Chinese)

[9] Baldi F , Coraddu A , Kalikatzarakis M . . Optimisation-based system designs for deep offshore wind farms including power to gas technologies. Applied Energy, 2022, 310: 118540

[10] Xiong B , Predel J , Crespo del Granado P . . Spatial flexibility in redispatch: Supporting low carbon energy systems with Power-to-Gas. Applied Energy, 2021, 283: 116201

[11] Ikäheimo J , Weiss R , Kiviluoma J . . Impact of power-to-gas on the cost and design of the future low-carbon urban energy system. Applied Energy, 2022, 305: 117713

[12] Wei F , Sui Q , Li X . . Optimal dispatching of power grid integrating wind-hydrogen systems. International Journal of Electrical Power & Energy Systems, 2021, 125: 106489

[13] Rabiee A , Keane A , Soroudi A . Green hydrogen: A new flexibility source for security constrained scheduling of power systems with renewable energies. International Journal of Hydrogen Energy, 2021, 46(37): 19270–19284

[14] Jiang Y, Yang G, Chen Y, et al. Optimal operation for the hydrogen network under consideration of the dynamic hydrogen production efficiency of electrolyzers. Proceedings of CSEE, 2023, 43(8): 3014–3026 (in Chinese)

[15] García-Valverde R , Espinosa N , Urbina A . Simple PEM water electrolyser model and experimental validation. International Journal of Hydrogen Energy, 2012, 37(2): 1927–1938

[16] Tsotridis G, Pilenga A. EU harmonized terminology for low temperature water electrolysis for energy-storage applications. 2018, available at Europa website

[17] Marocco P , Sundseth K , Aarhaug T . . Online measurements of fluoride ions in proton exchange membrane water electrolysis through ion chromatography. Journal of Power Sources, 2021, 483: 229179

[18] Marocco P , Ferrero D , Martelli E . . An MILP approach for the optimal design of renewable battery-hydrogen energy systems for off-grid insular communities. Energy Conversion and Management, 2021, 245: 114564

[19] Marocco P , Ferrero D , Lanzini A . . Optimal design of stand-alone solutions based on RES + hydrogen storage feeding off-grid communities. Energy Conversion and Management, 2021, 238: 114147

[20] Ulleberg I . Modeling of advanced alkaline electrolyzers: A system simulation approach. International Journal of Hydrogen Energy, 2003, 28(1): 21–33

[21] Schalenbach M , Carmo M , Fritz D L . . Pressurized PEM water electrolysis: Efficiency and gas crossover. International Journal of Hydrogen Energy, 2013, 38(35): 14921–14933

[22] Trinke P , Haug P , Brauns J . . Hydrogen crossover in PEM and alkaline water electrolysis: Mechanisms, direct comparison and mitigation strategies. Journal of the Electrochemical Society, 2018, 165(7): F502–F513

[23] Kotowicz J , Węcel D , Jurczyk M . Analysis of component operation in power-to-gas-to-power installations. Applied Energy, 2018, 216: 45–59

[24] Wang X , Star A G , Ahluwalia R K . Performance of polymer electrolyte membrane water electrolysis systems: Configuration, stack materials, turndown and efficiency. Energies, 2023, 16(13): 4964

[25] Espinosa-López M , Darras C , Poggi P . . Modelling and experimental validation of a 46 kW PEM high pressure water electrolyzer. Renewable Energy, 2018, 119: 160–173

[26] Giglio E , Lanzini A , Santarelli M . . Synthetic natural gas via integrated high-temperature electrolysis and methanation: Part I—Energy performance. Journal of Energy Storage, 2015, 1: 22–37

[27] Kotowicz J , Jurczyk M , Węcel D . The possibilities of cooperation between a hydrogen generator and a wind farm. International Journal of Hydrogen Energy, 2021, 46(10): 7047–7059

[28] Marocco P, Ferrero D, Santarelli M. REMOTE project, deliverable number 5.11 public report on performance analysis – Part 3. 2023

[29] Buttler A , Spliethoff H . Current status of water electrolysis for energy storage, grid balancing and sector coupling via power-to-gas and power-to-liquids: A review. Renewable & Sustainable Energy Reviews, 2018, 82: 2440–2454

[30] Marocco P , Gandiglio M , Santarelli M . Optimal design of PV-based grid-connected hydrogen production systems. Journal of Cleaner Production, 2024, 434: 140007

[31] Heras J , Martín M . Multiscale analysis for power-to-gas-to-power facilities based on energy storage. Computers & Chemical Engineering, 2021, 144: 107147

[32] Cruz V , Martín M . Martín M. Characterization and optimal site matching of wind turbines: Effects on the economics of synthetic methane production. Journal of Cleaner Production, 2016, 133: 1302–1311

[33] Li F , Bo R . Small test systems for power system economic studies. In: Proceedings of the IEEE PES General Meeting 2010, Minneapolis. IEEE, 2010,

[34] Wei F , Sui Q , Lin X . . Energy control scheduling optimization strategy for coal-wind-hydrogen energy grid under consideration of the efficiency features of hydrogen production equipment.. Proceedings of the CSEE, 2018, 38(5): 1428–1439 (in Chinese)

[35] InternationalEnergy Agency. Coal market update. 2023

[36] International Renewable Energy Agency. Making the breakthrough: Green hydrogen policies and technology costs. 2021

[37] Gao C , Wang W , Chen T . Capacity planning of electric-hydrogen integrated energy station based on reversible solid oxide battery. Proceedings of the CSEE, 2022, 42(17): 6155–6170

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