Power-to-gas system produces synthetic methane through two-step processes: H₂ production via water electrolysis and methanation of CO₂. The technology valorizes CO₂ as a useful commodity from biogas plants. Biogas upgrading technologies have the capacity to capture CO₂ and supply it as a source of carbon to methanation processes hence to produce synthetic methane. In this study, we have carried out a techno-economic assessment of biomethane production and estimation of its production costs via the integration of landfill biogas to methanation process. The study assessed four different scenarios, scenario 1: water-scrubbing, scenario 2: membrane, scenario 3: direct methanation and scenario 4: methanation with membrane. Production costs in case of power-to-gas scenarios 3&4 are competitive with standard upgrading scenarios 1&2 for electricity price below 20 €/MWh. Presence of electrolyzer unit contributes to more than 75% of the total biomethane production costs. Scenarios 1&2 are insensitive to changes in electricity prices as well as to operating time, but scenarios 3&4 are extremely sensitive to both electricity prices variation and operating time. Increase in the plant size and vol% of CH₄ in raw biogas presented shorter payback period in case of scenarios 1&2 due to lower specific production costs.

电转气系统通过两个步骤生产合成甲烷：通过水电解生产H ₂和 CO ₂甲烷化。该技术使 CO ₂成为沼气厂的有用商品。沼气升级技术具有捕获 CO ₂的能力并将其作为碳源提供给甲烷化过程，从而生产合成甲烷。在这项研究中，我们通过垃圾填埋场沼气与甲烷化过程的整合，对生物甲烷生产进行了技术经济评估并估算了其生产成本。该研究评估了四种不同的情景，情景 1：水洗，情景 2：膜，情景 3：直接甲烷化和情景 4：膜甲烷化。电转气方案 3 和 4 的生产成本与电价低于 20 欧元/兆瓦时的标准升级方案 1 和 2 相比具有竞争力。电解槽装置的存在占生物甲烷总生产成本的 75% 以上。场景 1&2 对电价变化和运行时间不敏感，但场景 3& 4 对电价变化和运行时间都极为敏感。增加工厂规模和 CH 的体积百分比由于特定生产成本较低，在情景 1 和 2 的情况下，原料沼气中的_{4 的}投资回收期较短。