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Hydrogen
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Hydrogen modeling in KiNESYS covers production pathways for "grey", "blue", "turquoise", and "green" hydrogen, with hydrogen production coupled to intermittent electricity production using detailed sub-annual time-slice modeling. The framework includes demand-side technologies for hydrogen use in industrial sectors, transportation, and the possibility of mixing in natural gas distribution systems.

Hydrogen Production Pathways
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**Production Technologies**
    KiNESYS models multiple hydrogen production technologies to produce different categories of hydrogen based on their carbon intensity and production methods:
    
    * **Grey hydrogen**: Conventional production from fossil fuels
    * **Blue hydrogen**: Fossil fuel-based production with carbon capture
    * **Turquoise hydrogen**: Methane pyrolysis producing solid carbon
    * **Green hydrogen**: Electrolytic production using renewable electricity

**Renewable Energy Integration**
    Hydrogen production can be coupled with intermittent electricity production, which is modeled in detail using a relatively detailed sub-annual time-slice approach for each modeling period. This enables optimization of electrolytic hydrogen production with variable renewable energy sources.

Hydrogen Trade Infrastructure
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**International Trade Modeling**
    Based on the H2_trade_cost_matrix data, KiNESYS models hydrogen trade through three main transport modes:
    
    * **Liquid Hydrogen (LH2)**: Cryogenic hydrogen transport
    * **Liquid Organic Hydrogen Carriers (LOHC)**: Chemical hydrogen carriers
    * **Ammonia**: Ammonia as hydrogen transport medium

**Export and Import Regions**
    The model includes bilateral trade links between selected export regions and demand regions:
    
    * **Export regions**: Australia, Chile, Saudi Arabia, Morocco, Norway, Canada, Oman, Namibia, UAE, South Africa, Russia, Kazakhstan, Iceland
    * **Import regions**: Major demand centers including Europe, Asia, and North America
    * **Trade costs**: Distance-based costs for production, conversion, transport, and reconversion

Hydrogen End-Use Applications
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**Industrial Sector Applications**
    Demand-side technologies for hydrogen consumption include:
    
    * **Industrial processes**: Hydrogen use in various industrial sectors
    * **Steel production**: Hydrogen applications in steel manufacturing
    * **Chemical industry**: Hydrogen as feedstock and process gas

**Transportation Sector**
    Hydrogen applications in transportation include:
    
    * **Heavy-duty vehicles**: Fuel cell trucks and buses
    * **Maritime transport**: Hydrogen and ammonia as marine fuels
    * **Aviation**: Potential hydrogen applications in aviation sector

**Natural Gas System Integration**
    * **Gas network blending**: Possibility of mixing hydrogen in natural gas distribution systems
    * **Infrastructure utilization**: Leveraging existing gas infrastructure for hydrogen transport