Presumptions for the Integration of Green Hydrogen and Biomethane Production in Wastewater Treatment Plants
Source abstract
Abstract
Achieving climate neutrality goals is inseparable from the sustainable development of modern cities. Municipal wastewater treatment plants (WWTP) are among the starting points when moving cities to Net-zero Greenhouse Gas (GHG) emissions and climate neutrality. This study focuses on the analysis of the integration of green hydrogen (H2) and biomethane technologies in WWTPs, and on the impact of this integration on WWTPs’ energy neutrality. This study treats WWTP as an integrated energy system with certain inputs and outputs. Currently, such systems in most cases have a significantly negative energy balance, and, in addition, fossil fuel energy sources are used. Key findings highlight that the integration of green hydrogen production in WWTPs and the efficient utilization of electrolysis by-products can make such energy systems neutral or even positive. This study provides an analysis of the main technical presumptions for the successful integration of green hydrogen and biomethane production processes in WWTP. Furthermore, a case study of a real wastewater treatment plant is presented.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Hybrid Renewable Energy Systems · Hydrogen Storage and Materials · Catalysts for Methane Reforming
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Lithuanian Energy Institute, Breslaujos St. 3, 44403 Kaunas, Lithuania
References (100+)
Show source-provided references
1. European Commission (2025, May 08). Questions and Answers on the New EU Rules on Treating Urban Wastewater. Available online: https://ec.europa.eu/commission/presscorner/detail/en/qanda_22_6281.
2. Wastewater treatment for carbon capture and utilization10.1038/s41893-018-0187-9 ↗
3. Net-zero carbon condition in wastewater treatment plants: A systematic review of mitigation strategies and challenges10.1016/j.rser.2023.113638 ↗
4. Integrated plant-wide modelling for evaluation of the energy balance and greenhouse gas footprint in large wastewater treatment plants10.1016/j.apenergy.2020.116126 ↗
5. European Union (2025, May 08). Directive (EU) 2024/3019 of the European Parliament and of the Council of 27 November 2024 Concerning Urban Wastewater Treatment (Recast). Available online: https://eur-lex.europa.eu/eli/dir/2024/3019/oj/eng.
6. European Union (2025, May 08). Directive (EU) 2018/2001 of the European Parliament and of the Council of 11 December 2018 on the Promotion of the Use of Energy from Renewable Sources (Recast). Consolidated Text: 2024-07-16. Available online: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A02018L2001-20240716.
7. European Commission (2025, May 08). Communication from the Commission to the European Parliament, the European Council, the Council, the European Economic and Social Committee and the Committee of the Regions: REPowerEU Plan (COM/2022/230 Final). Available online: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex:52022DC0230.
8. European Union (2025, May 08). Directive (EU) 2018/844 of the European Parliament and of the Council of 30 May 2018 Amending Directive 2010/31/EU on the Energy Performance of Buildings and Directive 2012/27/EU on Energy Efficiency. Available online: https://eur-lex.europa.eu/eli/dir/2018/844/oj/eng.
9. European Commission (2025, May 08). Commission Delegated Regulation (EU)/… Supplementing Directive (EU) 2018/2001 of the European Parliament and of the Council by Establishing a Union Methodology Setting Out Detailed rules for the Production of Renewable Liquid and Gaseous Transport Fuels of Non-Biological Origin (C/2023/1087 Final). Available online: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=pi_com%3AC%282023%291087.
10. European Commission (2025, May 08). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions. A Hydrogen Strategy for a Climate-Neutral Europe (COM/2020/301 Final). Available online: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A52020DC0301.
11. Gruber-Glatzl, W., Brunner, C., Meitz, S., and Schnitzer, H. (2020). From the Wastewater Treatment Plant to the Turnstiles of Urban Water and District Heating Networks. Front. Sustain. Cities, 2.10.3389/frsc.2020.523698 ↗
12. Drewnowski, J., Remiszewska-Skwarek, A., Duda, S., and Łagód, G. (2019). Aeration Process in Bioreactors as the Main Energy Consumer in a Wastewater Treatment Plant. Review of Solutions and Methods of Process Optimization. Processes, 7.10.3390/pr7050311 ↗
13. Operation of a circular economy, energy, environmental system at a wastewater treatment plant10.1016/j.adapen.2022.100109 ↗
14. Biomethane production using an integrated anaerobic digestion, gasification and CO2 biomethanation process in a real waste water treatment plant: A techno-economic assessment10.1016/j.enconman.2020.112663 ↗
15. The costs of future energy technologies: A comprehensive review of power-to-X processes10.1016/j.jcou.2025.103019 ↗
16. Sterner, M., and Specht, M. (2021). Power-to-Gas and Power-to-X—The History and Results of Developing a New Storage Concept. Energies, 14.10.3390/en14206594 ↗
17. Frontiers of CO2 Capture and Utilization (CCU) towards Carbon Neutrality10.1007/s00376-022-1467-x ↗
18. A “water and carbon” near-zero emission WWTP system: Model development and techno-economic-environmental benefits assessment10.1016/j.apenergy.2024.123727 ↗
19. Contribution to net zero emissions of integrating hydrogen production in wastewater treatment plants10.1016/j.jenvman.2023.118485 ↗
20. Hydrogen production from treated wastewater powered by solar–wind energy: Feasibility analysis and optimal planning10.1016/j.ijhydene.2024.09.296 ↗
21. Optimal planning and operation for a grid-connected solar–wind–hydro energy system in wastewater treatment plants10.1016/j.renene.2024.120791 ↗
22. Industrial decarbonisation oriented distributed renewable generation towards wastewater treatment sector: Case from the Yangtze River Delta region in China10.1016/j.energy.2022.124562 ↗
23. Exploring options for energy recovery from wastewater: Evaluation of hydropower potential in a sustainability framework10.1016/j.scs.2023.104576 ↗
24. Tomczyk, P., Mastalerek, K., Wiatkowski, M., Kuriqi, A., and Jurasz, J. (2023). Assessment of a Francis Micro Hydro Turbine Performance Installed in a Wastewater Treatment Plant. Energies, 16.10.3390/en16207214 ↗
25. Punys, P., and Jurevičius, L. (2022). Assessment of Hydropower Potential in Wastewater Systems and Application in a Lowland Country, Lithuania. Energies, 15.10.3390/en15145173 ↗
26. International Energy Agency (IEA) (2025, May 08). Global Hydrogen Review 2024. Available online: https://iea.blob.core.windows.net/assets/89c1e382-dc59-46ca-aa47-9f7d41531ab5/GlobalHydrogenReview2024.pdf.
27. Jacobs, Yarra Valley Water (2025, May 08). Towards a Zero Carbon Future. Available online: https://www.jacobs.com/sites/default/files/2022-03/jacobs-yarra-valley-water-towards-a-zero-carbon-future.pdf.
28. Biomethane production from biogas obtained in wastewater treatment plants: Process optimization and economic analysis10.1016/j.renene.2023.119469 ↗
29. A combined heat and green hydrogen (CHH) generator integrated with a heat network10.1016/j.enconman.2021.114686 ↗
30. Model-based dynamic simulation study to boost the WWTP performance in winter tourism regions10.1016/j.jwpe.2024.105266 ↗
31. Modelling and prediction of the effect of operational parameters on the fate of contaminants of emerging concern in WWTPs10.1016/j.scitotenv.2022.159200 ↗
32. Mitigating rural WWTP impacts: System dynamics modeling of downstream nutrient outputs10.1016/j.scitotenv.2020.140809 ↗
33. Impact of differences in speciation of organic compounds in wastewater from large WWTPs on technological parameters, economic efficiency and modelling of chemically assisted primary sedimentation process10.1016/j.jece.2020.104405 ↗
34. Variable emission factors of CH4 and N2O from WWTPs: A model-based analysis on available data10.1016/j.envres.2024.120380 ↗
35. Mitigating CH4 and N2O emissions from domestic and industrial wastewater10.1016/j.rser.2024.115203 ↗
36. Comprehensive assessment, intelligent prediction, and precise mitigation strategies for greenhouse gas emissions in full-scale wastewater treatment plants10.1016/j.envres.2025.121052 ↗
37. Novel extended hybrid tool for real time control and practically support decisions to reduce GHG emissions in full scale wastewater treatment plants10.1016/j.jenvman.2024.121502 ↗
38. Minimizing grid energy consumption in wastewater treatment plants: Towards green energy solutions, water sustainability, and cleaner environment10.1016/j.scitotenv.2024.172139 ↗
39. Achieving energy neutrality in wastewater treatment plants through energy savings and enhancing renewable energy production10.1007/s11157-018-9478-x ↗
40. Dissolved methane in anaerobic effluents: A review on sustainable strategies for optimization of energy recovery or internal process reuse10.1016/j.jclepro.2021.128359 ↗
41. Anaerobic digestion of livestock manure in cold regions: Technological advancements and global impacts10.1016/j.rser.2019.109494 ↗
42. Swedish Environmental Protection Agency (SEPA) (2012). Biogas ur Gödsel, Avfall och Restprodukter—Goda Svenska Exempel, SEPA. Available online: https://www.diva-portal.org/smash/get/diva2:1614170/FULLTEXT01.pdf.
43. Geographic distribution of net-zero energy wastewater treatment in China10.1016/j.rser.2021.111462 ↗
44. Indicator based multi-criteria decision support systems for wastewater treatment plants10.1016/j.scitotenv.2024.169903 ↗
45. Pascuzzi, S., Anifantis, A.S., Blanco, I., and Scarascia Mugnozza, G. (2016). Electrolyzer Performance Analysis of an Integrated Hydrogen Power System for Greenhouse Heating. A Case Study. Sustainability, 8.10.3390/su8070629 ↗
46. Potential of treated wastewater as an energy source for district heating: Incorporating social elements into a multi-factorial comparative assessment for cities10.1016/j.energy.2024.132190 ↗
47. Hydrogen and biomethane pathways to achieve sustainable transportation in circular economic concept: A review10.1016/j.ijhydene.2025.01.047 ↗
48. European Hydrogen Observatory (2025, May 08). Hydrogen Production. Available online: https://observatory.clean-hydrogen.europa.eu/hydrogen-landscape/production-trade-and-cost/hydrogen-production.
49. Nord Pool (2025, May 08). Prices. Available online: https://data.nordpoolgroup.com/auction/day-ahead/prices?deliveryDate=latest¤cy=EUR&aggregation=YearlyAggregate&deliveryAreas=GER.
50. Fan, Y., Lei, Z., Guo, Z., Huang, W., Wang, D., Wang, X., Zhang, Z., and Shimizu, K. (2020). Enhanced solubilization of solid organics and methane production by anaerobic digestion of swine manure under nano-bubble water addition. Bioresour. Technol., 299.10.1016/j.biortech.2019.122512 ↗
51. Utilisation of oxygen from water electrolysis—Assessment for wastewater treatment and aquaculture10.1016/j.ces.2021.117008 ↗
52. Environmental Protection Agency Ireland (EPA Ireland) (2025, May 08). Waste Water Treatment Manuals. Primary, Secondary and Tertiary Treatment. Available online: https://www.susana.org/_resources/documents/default/3-3017-7-1520420240.pdf.
53. Trace contaminants in biogas: Biomass sources, variability and implications for technology applications10.1016/j.jece.2024.114478 ↗
54. Biogas upgrading technologies—Recent advances in membrane-based processes10.1016/j.ijhydene.2022.10.228 ↗
55. Biodesulfurization: Effective and sustainable technologies for biogas hydrogen sulfide removal10.1016/j.rser.2024.115144 ↗
56. Sulfur-oxidizing bacteria in full-scale biogas cleanup system of ethanol industry10.1016/j.renene.2019.11.140 ↗
57. European Biogas Association (EBA) (2022). Statistical Report 2022: Tracking Biogas and Biomethane Deployment Across Europe, EBA. Available online: https://www.europeanbiogas.eu/__trashed-3/.
58. Macor, A., and Benato, A. (2020). Regulated Emissions of Biogas Engines—On Site Experimental Measurements and Damage Assessment on Human Health. Energies, 13.10.3390/en13051044 ↗
59. Aryal, N., Ottosen, L.D.M., Kofoed, M.V.W., and Pant, D. (2021). Chapter 11—Technologies for removal of hydrogen sulfide (H2S) from biogas. Emerging Technologies and Biological Systems for Biogas Upgrading, Academic Press.
60. Techno-economic review of biogas cleaning technologies for small scale off-grid solid oxide fuel cell applications10.1016/j.fuproc.2019.106215 ↗
61. Life cycle assessment of different physical-chemical and biological technologies for biogas desulfurization in sewage treatment plants10.1016/j.jclepro.2018.02.018 ↗
62. Corey, K., and Zappa, L. (2025, May 08). Global Environmental Solutions, Inc. Odor Control “ABC’s”. How to Compare and Evaluate Odor Control Technologies. Available online: http://gesodorcontrol.com/abcs.pdf.
63. Soreanu, G., and Dumont, É. (2020). Chapter 2—Biofilters versus bioscrubbers and biotrickling filters: State-of-the-art biological air treatment. From Biofiltration to Promising Options in Gaseous Fluxes Biotreatment, Elsevier.
64. Water electrolyzer operation scheduling for green hydrogen production: A review10.1016/j.rser.2024.114779 ↗
65. MCBioCH4: A computational model for biogas and biomethane evaluation10.1016/j.jclepro.2019.04.224 ↗
66. Biological hydrogen methanation systems—An overview of design and efficiency10.1080/21655979.2019.1684607 ↗
67. Use of surplus wind electricity in Ireland to produce compressed renewable gaseous transport fuel through biological power to gas systems10.1016/j.renene.2016.12.084 ↗
68. Synthetic natural gas production from biogas in a waste water treatment plant10.1016/j.renene.2019.07.044 ↗
69. Renewable Power-to-Gas: A technological and economic review10.1016/j.renene.2015.07.066 ↗
70. Biogas upgrading and utilization: Current status and perspectives10.1016/j.biotechadv.2018.01.011 ↗
71. Biological methanation: Strategies for in-situ and ex-situ upgrading in anaerobic digestion10.1016/j.apenergy.2018.11.006 ↗
72. Biological hydrogen methanation—A review10.1016/j.biortech.2017.08.176 ↗
73. Evaluation of biogas upgrading technologies and future perspectives: A review10.1007/s11356-019-04767-1 ↗
74. Ex-situ biogas upgrading and enhancement in different reactor systems10.1016/j.biortech.2016.11.124 ↗
75. Biological CO2 fixation in up-flow reactors via exogenous H2 addition10.1016/j.jbiotec.2020.05.012 ↗
76. Upgrading biogas produced in anaerobic digestion: Biological removal and bioconversion of CO2 in biogas10.1016/j.rser.2021.111448 ↗
77. Hollow fiber membrane based H2 diffusion for efficient in situ biogas upgrading in an anaerobic reactor10.1007/s00253-013-4811-3 ↗
78. Techno-economic analysis of biogas upgrading via amine scrubber, carbon capture and ex-situ methanation10.1016/j.apenergy.2017.12.099 ↗
79. Ericsson, K. (2017). Biogenic Carbon Dioxide as Feedstock for Production of Chemicals and Fuels: A Technoeconomic Assessment with a European Perspective, Miljö- och Energisystem, LTH, Lunds Universitet. Available online: https://lucris.lub.lu.se/ws/portalfiles/portal/31711760/Biogenic_carbon_dioxide_as_feedstock_for_production_of_chemicals_and_fuels_IMES_report_103.pdf.
80. Biocatalytic methanation of hydrogen and carbon dioxide in an anaerobic three-phase system10.1016/j.biortech.2014.08.023 ↗
81. Ministry of Energy of the Republic of Lithuania (2025, May 08). Frequently Asked Questions About Electricity Generating Consumers. Available online: https://enmin.lrv.lt/lt/veiklos-sritys-3/atsinaujinantys-energijos-istekliai/elektros-energija-gaminantys-vartotojai/dazniausiai-uzduodami-klausimai-apie-elektra-gaminancius-vartotojus/.
82. Seimas of the Republic of Lithuania (2025, May 08). Law of the Republic of Lithuania on Renewable Energy Resources Nr. XI-1375. Consolidated Text: 2025-01-23. Available online: https://e-seimas.lrs.lt/portal/legalAct/lt/TAD/TAIS.398874/asr.
83. Lithuanian Wind Power Association (LVEA) (2025, May 08). Wind Energy in Lithuania 2022. Available online: https://lvea.lt/en/lithuanian-statistics/.
84. Reliable energy recovery in an existing municipal wastewater treatment plant with a flow-variable micro-hydropower system10.1016/j.enconman.2015.06.016 ↗
85. Mérida García, A., Rodríguez Díaz, J.A., García Morillo, J., and McNabola, A. (2021). Energy Recovery Potential in Industrial and Municipal Wastewater Networks Using Micro-Hydropower in Spain. Water, 13.10.3390/w13050691 ↗
86. Distribution and characteristics of wastewater treatment plants within the global river network10.5194/essd-14-559-2022 ↗
87. European Small Hydropower Association (ESHA) (2004). Guide on How to Develop a Small Hydropower Plant, ESHA. [2nd ed.]. Available online: https://energycommunityplatform.eu/wp-content/uploads/2022/06/Merged-Guide-Develop-a-Small-Hydropower-Plant.pdf.
88. Ultra-low-head hydroelectric technology: A review10.1016/j.rser.2017.04.086 ↗
89. Potential of Micro Hydroelectric Generator Embedded at 30,000 PE Effluent Discharge of Sewerage Treatment Plant10.1051/e3sconf/20183402037 ↗
90. European Environment Agency (EEA) (2025, May 08). Greenhouse Gas Emission Intensity of Electricity Generation, Country Level. Chart (Interactive), Published 25 October 2024, Modified 15 April 2025. Available online: https://www.eea.europa.eu/en/analysis/indicators/greenhouse-gas-emission-intensity-of-1/greenhouse-gas-emission-intensity-of-electricity-generation-country-level.
91. European Hydrogen Backbone (EHB) (2025, May 08). European Hydrogen Infrastructure Map. Available online: https://ehb.eu/page/h2-infrastructure-map.
92. International Energy Agency (IEA) (2025, May 08). IEA Bioenergy Task 37—Country Reports Summaries 2019. Available online: https://www.ieabioenergy.com/wp-content/uploads/2020/03/IEA-Task-37-Country-Report-Summaries-2019-1.pdf.
93. Feasibility analysis of blending hydrogen into natural gas networks10.1016/j.ijhydene.2023.01.156 ↗
94. From the perspective of new technology of blending hydrogen into natural gas pipelines transmission: Mechanism, experimental study, and suggestions for further work of hydrogen embrittlement in high-strength pipeline steels10.1016/j.ijhydene.2021.12.108 ↗
95. A review of technical and regulatory limits for hydrogen blending in natural gas pipelines10.1016/j.ijhydene.2022.10.254 ↗
96. Minister of Energy of the Republic of Lithuania (2025, May 08). Order on Approval of Natural Gas Quality Requirements Nr. 1-194. Consolidated Text: 2024-12-10. Available online: https://e-seimas.lrs.lt/portal/legalAct/lt/TAD/TAIS.457419/asr.
97. Mahajan, D., Tan, K., Venkatesh, T., Kileti, P., and Clayton, C.R. (2022). Hydrogen Blending in Gas Pipeline Networks—A Review. Energies, 15.10.3390/en15103582 ↗
98. The state of district heating and cooling in Europe—A literature-based assessment10.1016/j.energy.2024.132191 ↗
99. The Association for Decentralised Energy (ADE) (2025, May 08). Market Report: Heat Networks in the UK. Available online: https://www.theade.co.uk/media/qh2npmkg/heat-networks-in-the-uk_v5-web-single-pages.pdf.
100. Tiktak, J. (2019). Heat Management of PEM Electrolysis: A Study on the Potential of Excess Heat from Medium-to Large-Scale PEM Electrolysis and the Performance Analysis of a Dedicated Cooling System. [Master’s Thesis, Delft University of Technology]. Available online: https://scispace.com/pdf/heat-management-of-pem-electrolysis-a-study-on-the-potential-13l7kpv6y9.pdf.