Connecting technologies

Connecting technologies#

This guide covers how to connect different technologies within H2Integrate, focusing on the technology_interconnections configuration and the power combiner and splitter components that enable complex system architectures.

Technology interconnections overview#

The technology_interconnections section in your plant configuration file defines how different technologies are connected within your system. This is how the H2I framework establishes the necessary OpenMDAO connections between your components based on these specifications.

Configuration format#

Technology interconnections are defined as an array of arrays in your plant_config.yaml:

technology_interconnections: [
  ["source_tech", "destination_tech", "variable_name", "transport_type"],
  ["tech_a", "tech_b", "shared_parameter"],
  ["tech_a", "tech_b", ["tech_a_param_name", "tech_b_param_name"]],
  # ... more connections
]

There are two connection formats:

4-element connections (transport components)#

["source_tech", "destination_tech", "variable_name", "transport_type"]

  • source_tech: Name of the technology providing the output

  • destination_tech: Name of the technology receiving the input

  • variable_name: The type of variable being transported (e.g., "electricity", "hydrogen", "ammonia")

  • transport_type: The transport component to use (e.g., "cable", "pipeline")

3-element connections (direct connections)#

Same shared parameter name#
["source_tech", "destination_tech", "shared_parameter"]

  • source_tech: Name of the technology providing the output

  • destination_tech: Name of the technology receiving the input

  • shared_parameter: The exact parameter name to connect (e.g., "capacity_factor", "electrolyzer_degradation")

Different shared parameter names#
["source_tech", "destination_tech", ("source_parameter", "destination_parameter")]

  • source_tech: Name of the technology providing the output

  • destination_tech: Name of the technology receiving the input

  • source_parameter: The name of the parameter within "source_tech"

  • destination_parameter: The name of the parameter within "destination_tech"

Internal connection logic#

H2Integrate processes these connections in the connect_technologies() method of h2integrate_model.py. Here's what happens internally:

  1. Transport component creation: For 4-element connections, H2Integrate creates a transport component instance and adds it to the OpenMDAO model with a unique name like {source}_to_{dest}_{transport_type}.

  2. Special handling for combiners and splitters: The system automatically tracks connection counts for combiners and splitters to handle their multiple inputs/outputs:

    • Splitters: Outputs are connected as electricity_out1, electricity_out2, etc.

    • Combiners: Inputs are connected as electricity_input1, electricity_input2, etc.

  3. Automatic OpenMDAO connections: The system creates the appropriate model.connect() calls to link the technologies through the transport components.

Example connection flow#

For a simple splitter configuration:

technology_interconnections: [
  ["wind_farm", "electricity_splitter", "electricity", "cable"],
  ["electricity_splitter", "electrolyzer", "electricity", "cable"],
  ["electricity_splitter", "doc", "electricity", "cable"],
]

This creates:

  1. wind_farm_to_electricity_splitter_cable component

  2. electricity_splitter_to_electrolyzer_cable component

  3. electricity_splitter_to_doc_cable component

And automatically connects:

  • wind_farm.electricity_out → wind_farm_to_electricity_splitter_cable.electricity_in

  • wind_farm_to_electricity_splitter_cable.electricity_out → electricity_splitter.electricity_in

  • electricity_splitter.electricity_out1 → electricity_splitter_to_electrolyzer_cable.electricity_in

  • electricity_splitter.electricity_out2 → electricity_splitter_to_doc_cable.electricity_in

Power combiner#

The power combiner is a simple but essential component that takes electricity from two sources and combines them into a single output without losses.

Configuration#

Add the combiner to your tech_config.yaml:

technologies:
  electricity_combiner:
    performance_model:
      model: "combiner_performance"

No additional configuration parameters are needed - the combiner simply adds the two input streams.

Inputs and outputs#

  • Inputs:

    • electricity_in1: Power from the first source (kW)

    • electricity_in2: Power from the second source (kW)

  • Output:

    • electricity_out: Combined power output (kW)

The relationship is straightforward: electricity_out = electricity_in1 + electricity_in2

Usage example#

technology_interconnections: [
  ["wind_farm", "electricity_combiner", "electricity", "cable"],
  ["solar_farm", "electricity_combiner", "electricity", "cable"],
  ["electricity_combiner", "electrolyzer", "electricity", "cable"],
]

This configuration combines wind and solar power before sending it to an electrolyzer.

Power splitter#

The power splitter is a more sophisticated component that takes electricity from one source and splits it between two outputs. It offers two operating modes to handle different system requirements.

Configuration#

Add the splitter to your tech_config.yaml:

technologies:
  electricity_splitter:
    performance_model:
      model: "splitter_performance"
      config:
        split_mode: "fraction"  # or "prescribed_electricity"
        fraction_to_priority_tech: 0.7  # for fraction mode
        # OR
        prescribed_electricity_to_priority_tech: 500.0  # for prescribed mode

Split modes#

Fraction mode (split_mode: "fraction")#

In fraction mode, you specify what fraction of the input power goes to the first technology:

config:
  split_mode: "fraction"
  fraction_to_priority_tech: 0.3  # 30% to first tech, 70% to second

  • Input parameter: fraction_to_priority_tech (0.0 to 1.0)

  • Behavior:

    • electricity_out1 = electricity_in × fraction

    • electricity_out2 = electricity_in × (1 - fraction)

Prescribed electricity mode (split_mode: "prescribed_electricity")#

In prescribed electricity mode, you specify an exact amount of power to send to the first technology:

config:
  split_mode: "prescribed_electricity"
  prescribed_electricity_to_priority_tech: 200.0  # 200 kW to first tech

  • Input parameter: prescribed_electricity_to_priority_tech (kW)

  • Behavior:

    • electricity_out1 = min(prescribed_amount, available_power)

    • electricity_out2 = electricity_in - electricity_out1

  • Smart limiting: If you request more power than available, the first output gets all available power and the second output gets zero

Note

The prescribed_electricity_to_priority_tech parameter can be provided as either a scalar value (constant for all time steps) or as a time-series array that varies throughout the simulation. This allows for sophisticated control strategies where you're meeting a desired load profile, or when the power split changes over time based on operational requirements, market conditions.

Inputs and outputs#

  • Input:

    • electricity_in: Total power input (kW)

    • Mode-specific inputs: either fraction_to_priority_tech or prescribed_electricity_to_priority_tech

  • Outputs:

    • electricity_out1: Power sent to the first technology (kW)

    • electricity_out2: Power sent to the second technology (remainder) (kW)

Usage example#

technology_interconnections: [
  ["offshore_wind", "electricity_splitter", "electricity", "cable"],
  ["electricity_splitter", "doc", "electricity", "cable"],      # first output
  ["electricity_splitter", "electrolyzer", "electricity", "cable"],    # second output
]

This sends part of the offshore wind power to a direct ocean capture system and the remainder to an electrolyzer.

Note

Each combiner handles exactly two inputs, and each splitter handles exactly two outputs. For more complex architectures, you can chain multiple components together.

Contents