Hidrogen merupakan salah satu sumber energi alternatif yang menjanjikan sebab terdapat potensi proses produksi tanpa emisi. Skema produksi hidrogen dapat melalui proses termokimia, biokimia, ataupun elektrokimia. Metode termokimia memiliki konversi yang tinggi namun menghasilkan emisi yang cukup besar. Di sisi lain, proses biokimia tidak menghasilkan emisi yang tinggi akan tetapi biaya yang tinggi dan konversi yang rendah. Penelitian ini menganalisis aspek teknis, lingkungan, dan ekonomi dengan mengevaluasi yield gas hidrogen, emisi CO2, dan levelized cost of hydrogen (LCOH). Perhitungan emisi mencakup scope 1 & 2. Percobaan dark fermentation dilakukan pada suhu 85°C menggunakan bakteri thermotoga neapolitana dengan variasi konsentrasi inokulum (0,3-0,7 g/L) pada perangkat lunak SuperPro Designer. Variasi metode pretreatment juga dilakukan antara metode steam explosion dan hidrolisis asam. Percobaan gasifikasi dilakukan pada perangkat lunak Aspen Plus V11 dengan variasi rasio uap-biomassa (0,8-1,2) dan variasi suhu (750-950°C). Berdasarkan hasil penelitian ditemukan bahwa dalam konfigurasi proses dengan hasil hidrogen tertinggi, hasil yield gasifikasi lebih tinggi (0,71 m3/kg jerami padi) dibandingkan proses dark fermentation (0,067 m3/kg jerami padi). Sedangkan dalam hal emisi yang dihasilkan dark fermentation unggul secara signifikan yaitu hanya sebesar 501 kg CO2eq, dimana gasifikasi menghasilkan 1480 ton CO2eq. Secara harga pokok produksi metode gasifikasi memiliki harga yang lebih rendah sekitar 0,7 USD/m3 dibandingkan dark fermentation yang mencapai 2,98 USD/m3. Jadi, dalam segi yield dan LCOH metode gasifikasi lebih unggul daripada dark fermentation. Namun, dark fermentation lebih baik dari segi emisi dibandingkan gasifikasi.

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Hydrogen represents a promising alternative energy carrier due to its potential for emission-free production. Various production pathways are available, including thermochemical, biochemical, and electrochemical processes. Thermochemical methods generally offer high conversion efficiencies but are accompanied by substantial greenhouse gas emissions. In contrast, biochemical processes such as dark fermentation tend to generate lower emissions but are hindered by low conversion rates and high production costs. This study presents a comparative assessment of the technical, environmental, and economic aspects of hydrogen production via dark fermentation and gasification. Emission calculations cover scopes 1 & 2. The analysis focuses on hydrogen yield, carbon dioxide equivalent (CO₂eq) emissions, and levelized cost of hydrogen (LCOH). Dark fermentation was simulated at 85°C using Thermotoga neapolitana with varying inoculum concentrations (0.3–0.7 g/L) and different pretreatment methods, namely steam explosion and acid hydrolysis, using SuperPro Designer. Gasification was modeled in Aspen Plus V11 with variations in steam-to-biomass ratio (0.8–1.2) and operating temperature (750–950°C). Results indicate that gasification yielded significantly more hydrogen (0.71 m³/kg rice straw) compared to dark fermentation (0.067 m³/kg rice straw). However, dark fermentation resulted in considerably lower emissions (501 kg CO₂eq) relative to gasification (1480 tons CO₂eq). From an economic perspective, gasification also achieved a lower LCOH at approximately 0.7 USD/m³, compared to 2.98 USD/m³ for dark fermentation. Overall, while gasification demonstrates superior yield and economic performance, dark fermentation offers notable environmental benefits