| Technology | Feed stock | Efficiency | Maturity | Reference |
| Steam reforming | Hydrocarbons | 70% - 85% | Commercial | [209] |
| Partial Oxidation | Hydrocarbons | 60% - 75% | Commercial | [209] |
| Autothermal reforming | Hydrocarbons | 60% - 75% | Near term | [209] |
| Plasma reforming | Hydrocarbons | 9% - 85% | Long term | [285] |
| Aqueous phase reforming | Carbohydrates | 35% - 55% | Med. Term | [321] |
| Ammonia decomposition | Ammonia | 28.3% | Near Term | [320] |
| Biomass gasification | Biomass | 35% - 50% | Commercial | [106] [117] [322] |
| Photolysis | Sunlight + Water | 0.5% | Long term | [323] |
| Dark fermentation | Biomass | 60% - 80% | Long term | [117] [163] |
| Photo fermentation | Biomass +Sunlight | 0.1% | Long term | [117] [322] |
| Microbial electrolysis cells | Biomass+ Electricity | 78% | Long term | [323] |
| Alkaline electrolyzer | H2O + Electricity | 50% - 60% | Commercial | [93] [322] |
| PEM electrolyzer | H2O + Electricity | 55% - 70% | Near term | [93] [322] |
| Solid oxide electrolysis cells | H2O + Electricity+ Heat | 40% - 60% | Med term | [106] |
| Thermochemical water splitting | H2O + Heat | NA | Long term | ΜΆ |
| Photo electrochemical water splitting | H2O + Sunlight | 12.4% | Long term | [93] [129] |