OMIEData

A Go library for accessing electricity market data from OMIE (Iberian Peninsula's Electricity Market Operator). This library provides data access for daily market prices and energy by technology for Spain and Portugal.

This is a Go port of the OMIEData Python library.

Table of Contents

• Features
• Installation
• Quick Start
  • Marginal Prices
  • Energy by Technology
  • Date Range Import
• Configuration
• Data Types
  • MarginalPriceData
  • TechnologyEnergy
• System Types
• Error Handling
• Historical Data Format Changes
• Examples
• Testing
• Acknowledgments

Features

• Marginal Prices: Hourly electricity prices for Spain and Portugal
• Energy by Technology: Generation breakdown by source (wind, solar, nuclear, etc.)
• Concurrent Downloads: Parallel data fetching
• Multiple Formats: Support for historical format changes
• Type Safety: Full Go type safety with proper error handling

Installation

go get github.com/devuo/omiedata

Quick Start

Marginal Prices

package main

import (
    "context"
    "fmt"
    "log"
    "time"

    "github.com/devuo/omiedata"
)

func main() {
    // Create importer
    importer := omiedata.NewMarginalPriceImporter()

    // Get data for yesterday
    ctx := context.Background()
    yesterday := time.Now().AddDate(0, 0, -1)

    data, err := importer.ImportSingleDate(ctx, yesterday)
    if err != nil {
        log.Fatal(err)
    }

    priceData := data.(*omiedata.MarginalPriceData)

    fmt.Printf("Date: %s\n", priceData.Date.Format("2006-01-02"))

    // Print hourly prices
    for hour := 1; hour <= 24; hour++ {
        if price, exists := priceData.SpainPrices[hour]; exists {
            fmt.Printf("Hour %2d: %.2f EUR/MWh\n", hour, price)
        }
    }
}

Energy by Technology

package main

import (
    "context"
    "fmt"
    "log"
    "time"

    "github.com/devuo/omiedata"
)

func main() {
    // Create importer for Iberian system
    importer := omiedata.NewEnergyByTechnologyImporter(omiedata.Iberian)

    ctx := context.Background()
    date := time.Date(2024, 1, 15, 0, 0, 0, 0, time.UTC)

    result, err := importer.ImportSingleDate(ctx, date)
    if err != nil {
        log.Fatal(err)
    }

    dayData := result.(*omiedata.TechnologyEnergyDay)

    fmt.Printf("Energy data for %s:\n", dayData.Date.Format("2006-01-02"))

    // Show renewable energy for each hour
    for _, record := range dayData.Records {
        renewable := record.Wind + record.SolarPV + record.SolarThermal + record.Hydro
        fmt.Printf("Hour %2d: %.1f MWh renewable\n", record.Hour, renewable)
    }
}

Date Range Import

// Import data for a week
start := time.Date(2024, 1, 1, 0, 0, 0, 0, time.UTC)
end := start.AddDate(0, 0, 6)

results, err := importer.Import(ctx, start, end)
if err != nil {
    log.Fatal(err)
}

dataList := results.([]*omiedata.MarginalPriceData)
fmt.Printf("Imported %d days of data\n", len(dataList))

Configuration

You can customize the import behavior with options:

options := omiedata.ImportOptions{
    Verbose:       true,           // Enable verbose logging
    MaxRetries:    5,              // Number of download retries
    RetryDelay:    2 * time.Second, // Delay between retries
    MaxConcurrent: 3,              // Maximum concurrent downloads
}

importer := omiedata.NewMarginalPriceImporterWithOptions(options)

Data Types

MarginalPriceData

Contains hourly electricity prices and energy volumes:

type MarginalPriceData struct {
    Date            time.Time
    SpainPrices     map[int]float64 // hour (1-24) -> EUR/MWh
    PortugalPrices  map[int]float64 // hour (1-24) -> EUR/MWh
    SpainBuyEnergy  map[int]float64 // hour (1-24) -> MWh
    SpainSellEnergy map[int]float64 // hour (1-24) -> MWh
    IberianEnergy   map[int]float64 // hour (1-24) -> MWh
    BilateralEnergy map[int]float64 // hour (1-24) -> MWh
}

TechnologyEnergy

Contains energy generation by technology for a specific hour:

type TechnologyEnergy struct {
    Date              time.Time
    Hour              int
    System            SystemType
    Coal              float64 // MWh
    Nuclear           float64 // MWh
    Wind              float64 // MWh
    SolarPV           float64 // MWh
    // ... other technologies
}

System Types

• omiedata.Spain (1) - Spanish market
• omiedata.Portugal (2) - Portuguese market
• omiedata.Iberian (9) - Combined Iberian market

Error Handling

The library uses structured error types:

data, err := importer.ImportSingleDate(ctx, date)
if err != nil {
    if omieErr, ok := err.(*types.OMIEError); ok {
        switch omieErr.Code {
        case types.ErrCodeNotFound:
            fmt.Println("Data not available for this date")
        case types.ErrCodeNetwork:
            fmt.Println("Network error occurred")
        case types.ErrCodeParse:
            fmt.Println("Failed to parse data")
        }
    }
    return err
}

Historical Data Format Changes

The library automatically handles OMIE's format changes over time:

• Pre-2009: Prices in Cent/kWh (automatically converted to EUR/MWh)
• 2009-2019: Transition period with format variations
• 2019+: Current EUR/MWh format

Examples

See the examples directory for complete working examples:

• marginal-price/ - Basic price data import
• energy-by-technology/ - Technology breakdown analysis
• average-price/ - Calculate average PT price for a date range

Run examples:

go run ./examples/marginal-price
go run ./examples/energy-by-technology
go run ./examples/average-price -start 01-01-2024 -end 03-01-2024

Testing

Run tests with sample data:

go test ./...

The test suite includes sample files from different time periods to ensure compatibility with format changes.

Acknowledgments

• Based on the original OMIEData Python library
• OMIE (Operador del Mercado Ibérico de Energía) for providing the data