> ## Documentation Index
> Fetch the complete documentation index at: https://docs.carbonpunk.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Emissions Calculation

> How Carbonpunk calculates transport emissions

## Emissions Calculation Methodology

Carbonpunk uses a robust methodology to calculate the carbon emissions associated with your logistics operations. Our approach is based on industry standards and best practices for greenhouse gas accounting.

### Basic Calculation Formula

The fundamental formula used for calculating transport emissions is:

```
Emissions (kg CO2e) = Activity Data × Emissions Factor
```

Where:

* **Activity Data** represents the transportation activity, typically measured as weight (tons) × distance (km)
* **Emissions Factor** is the amount of greenhouse gases emitted per unit of activity, specific to each transport mode

## Detailed Calculation Process

<Steps>
  <Step title="Data Collection">
    Carbonpunk collects essential shipment data including:

    * Origin and destination locations
    * Shipment weight
    * Transport mode
    * Date of shipment
    * Distance (if available)
  </Step>

  <Step title="Distance Calculation">
    If distance is not provided, Carbonpunk calculates it based on origin and destination coordinates using:

    * Great-circle distance for air transport
    * Road network distance for road transport
    * Rail network distance for rail transport
    * Shipping routes for sea transport
  </Step>

  <Step title="Emissions Factor Selection">
    The appropriate emissions factor is selected based on:

    * Transport mode (air, sea, road, rail)
    * Vehicle/vessel type (when available)
    * Fuel type (when available)
    * Region-specific factors (when applicable)
  </Step>

  <Step title="Emissions Calculation">
    The final calculation multiplies the activity data by the emissions factor:

    * For weight-based calculations: Weight (tons) × Distance (km) × Emissions Factor (kg CO2e/ton-km)
    * For volume-based calculations: Volume (m³) × Distance (km) × Emissions Factor (kg CO2e/m³-km)
  </Step>
</Steps>

## Transport Mode Specifics

Each transport mode has specific considerations in our emissions calculation methodology:

<AccordionGroup>
  <Accordion icon="plane" title="Air Transport">
    **Calculation Specifics**:

    * Includes radiative forcing effects (the additional climate impact of emissions at high altitude)
    * Considers aircraft type when available
    * Accounts for different emissions profiles for short, medium, and long-haul flights
    * Includes freight-specific load factors

    **Example Calculation**:
    A 500 kg shipment traveling 2,000 km by air might use an emissions factor of 1.2 kg CO2e/ton-km:

    ```
    0.5 tons × 2,000 km × 1.2 kg CO2e/ton-km = 1,200 kg CO2e
    ```
  </Accordion>

  <Accordion icon="truck" title="Road Transport">
    **Calculation Specifics**:

    * Varies by vehicle type (van, rigid truck, articulated truck)
    * Considers fuel efficiency and load factors
    * Accounts for regional differences in vehicle fleets
    * Includes empty running where applicable

    **Example Calculation**:
    A 2-ton shipment traveling 300 km by truck might use an emissions factor of 0.1 kg CO2e/ton-km:

    ```
    2 tons × 300 km × 0.1 kg CO2e/ton-km = 60 kg CO2e
    ```
  </Accordion>

  <Accordion icon="train" title="Rail Transport">
    **Calculation Specifics**:

    * Differentiates between electric and diesel traction
    * Considers regional electricity grid carbon intensity for electric trains
    * Accounts for load factors and train types

    **Example Calculation**:
    A 10-ton shipment traveling 800 km by electric train might use an emissions factor of 0.03 kg CO2e/ton-km:

    ```
    10 tons × 800 km × 0.03 kg CO2e/ton-km = 240 kg CO2e
    ```
  </Accordion>

  <Accordion icon="ship" title="Sea Transport">
    **Calculation Specifics**:

    * Varies by vessel type (container ship, bulk carrier, etc.)
    * Considers vessel size and capacity utilization
    * Accounts for port operations where applicable

    **Example Calculation**:
    A 20-ton shipment traveling 5,000 km by container ship might use an emissions factor of 0.015 kg CO2e/ton-km:

    ```
    20 tons × 5,000 km × 0.015 kg CO2e/ton-km = 1,500 kg CO2e
    ```
  </Accordion>
</AccordionGroup>

## Emissions Factors Sources

Carbonpunk uses emissions factors from reputable sources, including:

* **GLEC Framework** (Global Logistics Emissions Council)
* **DEFRA** (UK Department for Environment, Food and Rural Affairs)
* **EPA** (US Environmental Protection Agency)
* **EcoTransIT World**
* **ICAO** (International Civil Aviation Organization)
* **IMO** (International Maritime Organization)

These factors are regularly updated to reflect the latest research and technological developments in the transport sector.

## Data Quality and Uncertainty

The accuracy of emissions calculations depends on the quality of input data:

| Data Quality Level | Description                                           | Uncertainty Range |
| ------------------ | ----------------------------------------------------- | ----------------- |
| High               | Primary data with specific vehicle/vessel information | ±5-10%            |
| Medium             | Mode-specific data with standard emissions factors    | ±10-25%           |
| Low                | Estimated data with default values                    | ±25-50%           |

Carbonpunk strives to use the highest quality data available and clearly indicates the level of certainty in emissions calculations.

## Related Features

<CardGroup>
  <Card title="Transport Overview" icon="truck" href="/transport/overview">
    Learn about different transport modes and their environmental impact
  </Card>

  <Card title="Data Import" icon="file-import" href="/essentials/data-import">
    Import the data needed for emissions calculations
  </Card>

  <Card title="Reports" icon="file-lines" href="/essentials/reports">
    Generate detailed emissions reports
  </Card>
</CardGroup>