Configure Capacity Reserve Requirements¶

This guide shows how to specify capacity reserve credit values for different technologies and constraints in PowerGenome. It covers both simple and complex scenarios using the capacity_reserve_values and regional_capacity_reserves settings.

Overview¶

Capacity reserve requirements define how much capacity different technologies contribute to meeting reserve obligations. PowerGenome supports specifying these values in a user-friendly way that automatically populates the underlying regional_tag_values structure.

Basic Setup: Uniform Technology Credits¶

For systems where technologies get the same credit values across all capacity reserve constraints, use the flat format:

regional_capacity_reserves:
  CapRes_1:
    p1: 0.164
    p2: 0.164
    p3: 0.164
  CapRes_2:
    p1: 0.090
    p2: 0.090
    p3: 0.090

capacity_reserve_values:
  Conventional Steam Coal: 0.9
  Natural Gas Fired Combined Cycle: 0.9
  Onshore Wind Turbine: 0.15
  Utility Solar Photovoltaic: 0.25
  Hydroelectric: 1.0
  Nuclear: 1.0

In this format:

All technologies listed in capacity_reserve_values receive the same credit values
These values apply to all capacity reserve constraints in regional_capacity_reserves
Each region gets populated automatically with the technology credits

Result (internally):

regional_tag_values:
  p1:
    CapRes_1:
      Conventional Steam Coal: 0.9
      Natural Gas Fired Combined Cycle: 0.9
      Onshore Wind Turbine: 0.15
      Utility Solar Photovoltaic: 0.25
      Hydroelectric: 1.0
      Nuclear: 1.0
    CapRes_2:
      Conventional Steam Coal: 0.9
      Natural Gas Fired Combined Cycle: 0.9
      Onshore Wind Turbine: 0.15
      Utility Solar Photovoltaic: 0.25
      Hydroelectric: 1.0
      Nuclear: 1.0
  p2:
    CapRes_1:
      Conventional Steam Coal: 0.9
      ...
    CapRes_2:
      Conventional Steam Coal: 0.9
      ...
  # Similar structure for p3

Advanced Setup: Multiple Constraints¶

For systems where technologies have different credit values depending on the constraint, use the nested format:

regional_capacity_reserves:
  CapRes_1:
    p1: 0.164
    p2: 0.164
    p3: 0.164
  CapRes_2:
    p4: 0.180
    p5: 0.180
    p6: 0.180
  CapRes_3:
    p1: 0.090
    p2: 0.090
    p3: 0.090
    p4: 0.090
    p5: 0.090
    p6: 0.090

capacity_reserve_values:
  CapRes_1:
    Conventional Steam Coal: 0.85
    Natural Gas Fired Combined Cycle: 0.85
    Onshore Wind Turbine: 0.05
    Hydroelectric: 1.0
    Nuclear: 1.0
  CapRes_2:
    Conventional Steam Coal: 0.95
    Natural Gas Fired Combined Cycle: 0.95
    Onshore Wind Turbine: 0.25
    Utility Solar Photovoltaic: 0.40
    Hydroelectric: 1.0
    Nuclear: 1.0
  CapRes_3:
    Conventional Steam Coal: 0.9
    Natural Gas Fired Combined Cycle: 0.9
    Onshore Wind Turbine: 0.15
    Utility Solar Photovoltaic: 0.25
    Hydroelectric: 1.0
    Nuclear: 1.0

In this format:

Each constraint has its own credit values for technologies
Constraints can have different requirements in different regions
Technologies can have different credits depending on the constraint

Result (internally):

regional_tag_values:
  p1:
    CapRes_1:
      Conventional Steam Coal: 0.85
      Natural Gas Fired Combined Cycle: 0.85
      ...
    CapRes_3:
      Conventional Steam Coal: 0.9
      ...
  p4:
    CapRes_2:
      Conventional Steam Coal: 0.95
      ...
    CapRes_3:
      Conventional Steam Coal: 0.9
      ...

Mixing Automatic and Manual Configuration¶

You can mix the automatic expansion with manual regional_tag_values overrides for specific regions or constraints:

capacity_reserve_values:
  Tech1: 0.9
  Tech2: 0.9

regional_capacity_reserves:
  CapRes_1:
    p1: 0.164
    p2: 0.164

# Manual overrides for special cases
regional_tag_values:
  p1:
    CapRes_1:
      Tech1: 0.95  # Different credit for p1

Result (merged):

p1/CapRes_1/Tech1: 0.95 (explicit override)
p1/CapRes_1/Tech2: 0.9 (auto-expanded)
p2/CapRes_1/Tech1: 0.9 (auto-expanded)
p2/CapRes_1/Tech2: 0.9 (auto-expanded)

Explicit entries always take precedence over auto-generated values, allowing you to override specific cells while benefiting from automation elsewhere.

Scenario-Specific Values¶

You can use the scenario management system to vary capacity reserve values across different cases:

# Base settings
capacity_reserve_values:
  Coal: 0.9
  Natural Gas: 0.9

settings_management:
  all_years:
    reserve_policy:
      conservative:
        capacity_reserve_values:
          Coal: 0.8      # Lower credit in conservative scenario
          Natural Gas: 0.8
      aggressive:
        capacity_reserve_values:
          Coal: 1.0      # Higher credit in aggressive scenario
          Natural Gas: 1.0

Then in your scenario definitions file, set reserve_policy to conservative or aggressive for each case. PowerGenome will automatically expand the scenario-specific capacity_reserve_values for each case.

Technology Name Matching¶

Technology names in capacity_reserve_values must match the technology names in your generator data exactly (case-sensitive). Common technology names in PowerGenome include:

Conventional Steam Coal
Natural Gas Fired Combined Cycle
Natural Gas Fired Combustion Turbine
Onshore Wind Turbine
Utility Solar Photovoltaic
Distributed Solar Photovoltaic
Hydroelectric
Nuclear
Battery Storage

You can also create custom new-build resources with their own names, which will work with capacity_reserve_values as long as the names match.

Tips and Best Practices¶

Use the flat format for uniform credits: If all your technologies have the same credit values across all constraints, the flat format is simpler and easier to maintain.
Use the nested format for varying credits: If technology credits differ by constraint, use the nested format to specify each constraint separately.
Keep constraint names consistent: Use the naming scheme CapRes_1, CapRes_2, CapRes_3, etc. and stick with it throughout your settings.
Document constraint meanings: Add comments explaining what each constraint represents:

regional_capacity_reserves:
  CapRes_1:  # Primary reserve requirement (MW)
    p1: 0.164

Validate your values: Ensure technology credit values are between 0 and 1. Values represent the fraction of installed capacity that counts toward the reserve requirement:
1.0: Fully counts (e.g., baseload coal, nuclear)
0.5: Half credit (e.g., wind, which has low capacity factor)
0.0: Zero credit (doesn't contribute)
Use scenario variations for sensitivity analysis: Explore how reserve policies affect the optimal mix by creating different cases with varying capacity_reserve_values.

Troubleshooting¶

Settings not taking effect?

Check that capacity_reserve_values and regional_capacity_reserves are both present in your settings.
Verify that technology names match exactly (spaces, capitalization, hyphens).
Ensure model_regions includes all regions referenced in regional_capacity_reserves.

Different constraints getting same credits unexpectedly?

This is the intended flat format behavior. Use nested format if constraints should have different credits per technology.

Explicit regional_tag_values being ignored?

Remember that explicit entries in regional_tag_values take precedence. If you want automatic values, don't specify them in regional_tag_values.