Grid¶

The grid represents your connection to the electricity network. It allows bidirectional power flow: importing (buying) and exporting (selling) electricity.

Configuration¶

Grid configuration uses a two-step flow (see Configuration for details):

1. Step 1: Enter name, connection, and select input mode for each field (Constant, Entity Link, or Not Configured)
2. Step 2: Enter values or select sensors based on your mode selections

Name¶

Unique identifier for this grid within your HAEO configuration. Used to create sensor entity IDs and identify the grid in connections.

Examples: "Main Grid", "Grid Connection", "Utility"

Import Price¶

Configure the cost of importing electricity from the grid. You can use either a constant value or one or more Home Assistant sensors.

Constant value: Enter a fixed price in $/kWh that stays the same for all periods. Use this for simple flat-rate tariffs.

Entity Link: Select one or more Home Assistant sensors providing electricity import pricing. Use this for time-of-use rates or dynamic pricing.

Sign convention: Import prices should be positive numbers representing the cost you pay to buy electricity from the grid. For example, 0.25 means you pay $0.25 per kWh imported.

Sensor examples:

When using sensors, provide all relevant price sensors (today, tomorrow, etc.) to ensure complete horizon coverage. See the Forecasts and Sensors guide for details on how HAEO processes sensor data.

Export Price¶

Configure the revenue for exporting electricity to the grid. You can use either a constant value or one or more Home Assistant sensors.

Constant value: Enter a fixed price in $/kWh. Use this for simple feed-in tariffs.

Entity Link: Select one or more Home Assistant sensors providing export pricing. Use this for dynamic feed-in rates.

Sign convention: Export prices should be positive numbers representing the revenue you receive for selling electricity to the grid. For example, 0.10 means you receive $0.10 per kWh exported.

Typical relationship: Export price is usually lower than import price.

• Import: $0.25/kWh (what you pay to buy)
• Export: $0.10/kWh (what you receive to sell)

This price difference incentivizes self-consumption and strategic battery usage.

Negative export prices: When the grid operator charges you to export use negative values. For example, -0.05 means you pay $0.05 per kWh to export.

Import Limit¶

Maximum power that can be imported from the grid (kW).

Optional: Select "Not Configured" in step 1 to leave import unlimited. You can also use a constant value or link to a sensor for dynamic limits.

Use this to model:

• Main breaker capacity (e.g., 60A × 240V ÷ 1000 = 14.4 kW)
• Grid connection agreement limits
• Distribution network constraints
• Regulatory import restrictions

Example: 15 for 15 kW maximum import

Export Limit¶

Maximum power that can be exported to the grid (kW).

Optional: Select "Not Configured" in step 1 to leave export unlimited. You can also use a constant value or link to a sensor for dynamic limits.

Use this to model:

• Inverter export capacity
• Grid connection agreement limits
• Feed-in tariff restrictions
• Regulatory export caps (zero-export requirements, etc.)

Example: 10 for 10 kW maximum export

Zero export: Set to 0 to prevent any grid export (self-consumption only mode)

Configuration Examples¶

Dynamic Pricing with Forecasts¶

Use Entity Link mode with multiple sensors for time-varying pricing:

Fixed Pricing¶

Use Constant mode for fixed rates, or Entity Link with an input_number for adjustable rates:

For more examples and sensor configuration, see the Forecasts and Sensors guide.

Input Entities¶

Each configured field creates a corresponding input entity in Home Assistant. Input entities appear as Number entities with the config entity category.

Input entities are only created for fields you configure. If you select "Not Configured" for a limit field, no input entity is created for that field.

Input entities include a forecast attribute showing values for each optimization period. See the Input Entities developer guide for details on input entity behavior.

Sensors Created¶

Sensor Summary¶

A Grid element creates 1 device in Home Assistant with the following sensors.

The power_max_* sensors are only created when the corresponding limit is configured. The cost_* sensors are only created when the corresponding price is configured.

Import Power¶

The optimal power being imported from the grid at each time period.

Values are always positive or zero. When importing, this represents electricity you're buying from the utility. A value of 0 means no import is occurring (either self-sufficient or exporting).

Example: A value of 3.5 kW means the optimization determined that importing 3.5 kW from the grid at this time minimizes total system cost.

Export Power¶

The optimal power being exported to the grid at each time period.

Values are always positive or zero. When exporting, this represents electricity you're selling back to the utility. A value of 0 means no export is occurring (either self-consuming all generation or importing).

Example: A value of 2.1 kW means the optimization determined that exporting 2.1 kW to the grid at this time maximizes total system value (typically during high export prices or excess generation).

Import Cost¶

The cost of electricity imported from the grid at each time period. Calculated as import price multiplied by import power multiplied by period duration.

Values are always positive or zero, representing money you pay to the utility. Only created when an import price is configured.

Example: A value of $0.50 means you're paying $0.50 to import electricity during this time period.

Export Cost¶

The revenue from electricity exported to the grid at each time period. Calculated as export price multiplied by export power multiplied by period duration.

Values are always negative or zero, representing money you earn from the utility (revenue is shown as negative cost). Only created when an export price is configured.

Example: A value of -$0.30 means you're earning $0.30 from exporting electricity during this time period.

Net Cost¶

The net cost of grid usage at each time period. Calculated as import cost plus export cost.

When both import and export prices are configured, this shows your net spending or earnings. Positive values mean net spending; negative values mean net earnings.

Example: If you import $0.50 worth and export $0.30 worth in a period, the net cost is $0.20 (net spending).

Max Import Power¶

The configured maximum import power limit. Only created when an import limit is configured.

Shows the power limit used in the optimization.

Max Export Power¶

The configured maximum export power limit. Only created when an export limit is configured.

Shows the power limit used in the optimization.

Max Import Power Shadow Price¶

The marginal value of additional import capacity. See the Shadow Prices modeling guide for general shadow price concepts.

This shadow price shows how much the total system cost would decrease if the import limit were increased by 1 kW at this time period.

Interpretation:

• Zero value: Import limit is not constraining (you're importing below the limit or not importing at all)
• Positive value: Import limit is binding and constraining the optimization
  • The value represents how much system cost would decrease per kW of additional import capacity
  • Higher values indicate the import limit is causing significant cost increases
  • Suggests that more import capacity would be valuable at this time

Example: A value of 0.15 means that if you could import 1 kW more, the total system cost would decrease by $0.15 at this time period.

Max Export Power Shadow Price¶

The marginal value of additional export capacity. See the Shadow Prices modeling guide for general shadow price concepts.

This shadow price shows how much the total system cost would decrease if the export limit were increased by 1 kW at this time period.

Interpretation:

• Zero value: Export limit is not constraining (you're exporting below the limit or not exporting at all)
• Positive value: Export limit is binding and constraining the optimization
  • The value represents how much system cost would decrease per kW of additional export capacity
  • Higher values indicate the export limit is preventing valuable exports
  • Suggests that more export capacity would be valuable at this time

Example: A value of 0.08 means that if you could export 1 kW more, the total system cost would decrease by $0.08 at this time period (you'd earn more revenue from exports).

All sensors include a forecast attribute containing future optimized values for upcoming periods.

Troubleshooting¶

Sensor Not Found¶

Problem: Error "Sensors not found or unavailable"

Solutions:

• Verify sensor entity IDs exist in Home Assistant
• Check sensors are available (not "unavailable" or "unknown")
• Ensure pricing integration is configured correctly
• Verify sensors have appropriate device class (e.g., monetary for prices)

Incorrect Price Values¶

Problem: Price values don't match expectations

Check:

• Sensor units match HAEO expectations (uses Home Assistant's native currency units)
• Multiple sensors sum correctly (intended?)
• Forecast data quality from source
• Import price > export price (prevents arbitrage)

Grid Not Optimizing¶

Problem: Grid always imports or never responds to price changes

Possible causes:

• Prices are constant (no optimization needed)
• Battery at SOC limits
• Grid not connected to other elements
• Load exceeds available supply

Solutions:

• Verify price sensors provide varying values
• Check battery SOC limits and capacity
• Review connections in network configuration
• Check grid import limit vs total load

Next Steps¶