Understanding Transportation Emissions
Category 3 under ISO 14064-1 covers indirect GHG emissions from transportation not covered in Categories 1 or 2. This includes transportation of materials, products, waste, employees, and business travelers using vehicles NOT owned or controlled by your organization.Transportation Emission FormulaTransport Emissions = Distance × Emission FactorOr with weight:Freight Emissions = Distance × Weight × Emission Factor (per tonne-km)Where emission factors vary by transport mode, vehicle type, and load factor.
Prerequisites
Before starting, ensure you have:- Dcycle API credentials (get them here)
- Travel records (bookings, expense reports, travel agency data)
- Employee commuting survey data or estimates
- Freight shipment records (origin, destination, weight)
Data Map: Category 3 Requirements
Business Travel
Track emissions from employee business trips including flights, ground transportation, and hotel stays.Record Flight Travel
📋 Data Map: Flight Travel
📋 Data Map: Flight Travel
| Field | Type | Required | Description | Example |
|---|---|---|---|---|
transport_type | string | ✅ | Type of transport | "aircraft" |
origin | string | ✅* | Origin airport code (IATA) | "MAD" |
destination | string | ✅* | Destination airport code (IATA) | "LHR" |
distance_km | number | ✅* | Distance in km (*either origin+destination OR distance_km) | 1264 |
start_date | date | ✅ | Travel start date | "2024-03-15" |
end_date | date | ✅ | Travel end date | "2024-03-15" |
travel_type | string | ❌ | One-way or round trip | "one_way", "round" |
travel_number | int | ❌ | Number of trips (defaults to 1) | 1 |
renewable_energy | string | ❌ | Uses renewable energy? | "yes", "no", "do_not_know" |
name | string | ❌ | Employee name | "John Smith" |
email | string | ❌ | Employee email | "[email protected]" |
- Travel bookings: Corporate travel systems, travel agencies
- Expense reports: Employee expense claims
- Airport codes: IATA 3-letter codes (e.g., MAD, LHR, JFK)
Distance or Locations RequiredYou must provide either
distance_km OR both origin and destination. If you provide airport codes, Dcycle automatically calculates the distance.Automatic Distance CalculationWhen you provide information for origin and destination, Dcycle automatically:
- Calculates the flight distance
- Determines the aircraft size category (very short, short, medium, long haul) based on Ecoinvent classification
- Applies the appropriate emission factor from Ecoinvent
Record Rail Travel
📋 Data Map: Rail Travel
📋 Data Map: Rail Travel
| Field | Type | Required | Description | Example |
|---|---|---|---|---|
transport_type | string | ✅ | Type of transport | "train" |
origin | string | ✅* | Origin city/station | "Madrid" |
destination | string | ✅* | Destination city/station | "Barcelona" |
distance_km | number | ✅* | Distance in km (*either origin+destination OR distance_km) | 620 |
start_date | date | ✅ | Travel start date | "2024-04-10" |
end_date | date | ✅ | Travel end date | "2024-04-10" |
travel_type | string | ❌ | One-way or round trip | "one_way", "round" |
travel_number | int | ❌ | Number of trips | 1 |
renewable_energy | string | ❌ | Train uses renewable energy? | "yes", "no", "do_not_know" |
Record Car Rental / Ground Transport
📋 Data Map: Car Travel
📋 Data Map: Car Travel
| Field | Type | Required | Description | Example |
|---|---|---|---|---|
transport_type | string | ✅ | Type of transport | "car" |
origin | string | ✅* | Origin location | "Madrid" |
destination | string | ✅* | Destination location | "Toledo" |
distance_km | number | ✅* | Distance in km (*either origin+destination OR distance_km) | 350 |
vehicle_size | string | ✅ | Vehicle size (required for car) | "small", "medium", "large" |
fuel_type | string | ✅ | Fuel type (required for car) | "diesel", "petrol", "electric", "hybrid", "lpg" |
start_date | date | ✅ | Travel start date | "2024-05-20" |
end_date | date | ✅ | Travel end date | "2024-05-20" |
travel_type | string | ❌ | One-way or round trip | "one_way", "round" |
travel_number | int | ❌ | Number of trips | 1 |
Employee Commuting
Employee commuting covers emissions from the transportation of employees between their homes and worksites in vehicles not owned or operated by your organization. This includes:- Daily commuting: Regular home-to-work travel
- All transport modes: Car, public transit, cycling, walking
- Remote work: Zero emissions for work-from-home days
- Carpooling: Shared vehicle emissions (divided among passengers)
Employee Commuting vs Business Travel
- Employee Commuting: Daily travel between home and work
- Business Travel: Trips for business purposes (meetings, conferences, site visits)
Data Map: Employee Commuting Overview
Weekly Travels (Working Days)
Theweekly_travels field defines which days of the week the employee commutes:
| Day | Value | Description |
|---|---|---|
| Monday | 0 | Included if present in array |
| Tuesday | 1 | Included if present in array |
| Wednesday | 2 | Included if present in array |
| Thursday | 3 | Included if present in array |
| Friday | 4 | Included if present in array |
| Saturday | 5 | Included if present in array |
| Sunday | 6 | Included if present in array |
| Pattern | weekly_travels | Description |
|---|---|---|
| Full week (Mon-Fri) | [0, 1, 2, 3, 4] | Traditional 5-day week |
| 3 days/week | [0, 2, 4] | Mon, Wed, Fri only |
| Hybrid (2 days) | [1, 3] | Tue, Thu in office |
| Full remote | [] | Empty = no commuting |
Remote Work / TeleworkSet
weekly_travels: [] (empty array) for fully remote employees. Dcycle will calculate zero commuting emissions for these employees.Transport Types
| Transport Type | Description | Typical EF Range |
|---|---|---|
car | Personal vehicle | 0.1-0.2 kg CO₂e/km |
bus | Public bus | 0.05-0.1 kg CO₂e/km |
train | Commuter rail | 0.03-0.05 kg CO₂e/km |
metro | Urban subway | 0.02-0.04 kg CO₂e/km |
trolleybus | Electric trolley | 0.02-0.04 kg CO₂e/km |
motorbike | Motorcycle | 0.08-0.12 kg CO₂e/km |
bicycle | Cycling | 0 kg CO₂e/km |
walk | Walking | 0 kg CO₂e/km |
| Vehicle Size | Fuel Type | Description |
|---|---|---|
small | petrol, diesel, electric, hybrid, lpg, natural_gas | Compact cars |
medium | petrol, diesel, electric, hybrid, lpg, natural_gas | Sedans |
large | petrol, diesel, electric, hybrid, lpg, natural_gas | SUVs |
CarpoolingWhen
carpool: true, emissions are divided by 3 (average carpool occupancy). This encourages shared transportation and accurately reflects the lower per-person emissions.Step 1: Create Employee Records
📋 Data Map: Employee Record
📋 Data Map: Employee Record
| Field | Type | Required | Description | Example |
|---|---|---|---|---|
origin | string | ⚠️ | Home address/city | "Madrid, Spain" |
destination | string | ⚠️ | Office address | "Company HQ, Madrid" |
total_km | number | ⚠️ | One-way distance | 15 |
transport_type | string | ✅ | Commute mode | "car" |
weekly_travels | array | ✅ | Days in office [0-6] | [0, 1, 2, 3, 4] |
email | string | ❌ | Employee email | "[email protected]" |
name | string | ❌ | Employee name | "John Smith" |
vehicle_size | string | ❌ | For cars | "medium" |
fuel_type | string | ❌ | For cars | "petrol" |
carpool | boolean | ❌ | Shared vehicle | false |
- Either
origin+destinationORtotal_kmmust be provided
- Home location: HR records, employee surveys
- Transport mode: Employee surveys
- Working days: HR/scheduling systems
Common Commuting Scenarios
Step 2: Send Employee Surveys
Collect commuting data directly from employees via survey:Survey QuestionsDcycle’s commuting survey asks employees:
- Home location (address or postal code)
- Primary transport mode
- Vehicle details (if car)
- Days worked in office per week
- Carpooling (yes/no)
Step 3: Bulk Upload Employee Data
For organizations with many employees, use CSV upload:CSV Format
CSV Notes:
total_kmis one-way distance (home to office)weekly_travelsuse format"[0,1,2,3,4]"(JSON array as string)- Empty
"[]"for remote workers carpool:trueorfalse
Upload CSV
Commuting Reduction Strategies
Upstream Transportation
Track emissions from inbound freight - materials and products shipped TO your organization.📋 Data Map: Upstream Freight
📋 Data Map: Upstream Freight
| Field | Type | Required | Description | Example |
|---|---|---|---|---|
direction | string | ✅ | Upstream or downstream | "upstream" |
origin | string | ✅ | Origin location | "Shanghai, China" |
destination | string | ✅ | Destination (your facility) | "Madrid, Spain" |
transport_mode | string | ✅ | Mode of transport | "sea", "road", "rail", "air" |
weight_tonnes | number | ✅ | Shipment weight | 25 |
date | date | ✅ | Shipment date | "2024-02-15" |
- Shipment details: Supplier invoices, shipping documents
- Weight: Bill of lading, packing lists
- Origin: Supplier locations
Downstream Transportation
Track emissions from outbound freight - products shipped FROM your organization to customers.Upstream vs Downstream Classification
- Upstream: Inbound goods, raw materials from suppliers, waste sent for treatment
- Downstream: Outbound products to customers, deliveries to distribution centers
Query Category 3 Emissions
Retrieve all your transportation emissions for reporting:Emission Factors
Dcycle uses emission factors from Ecoinvent 3.8 cutoff by classification for all Category 3 transportation calculations. Factors are automatically selected based on transport type, distance, vehicle characteristics, and regional variations.Business Travel (Flights)
Emission Factor Sources
Emission Factor Sources
For aircraft travel, emission factors are selected based on:
- Aircraft size category (very short, short, medium, long haul - determined by distance following Ecoinvent classification)
- Origin location (regional adjustments)
- Transport type (aircraft)
- Renewable energy (if applicable)
Aircraft Size Categories
Aircraft Size Categories
Dcycle automatically determines the aircraft size based on flight distance:
These distance thresholds are defined by Ecoinvent documentation for passenger air transport.Note: Cabin class (economy, business, first) is NOT used in calculations. Dcycle calculates emissions based on average passenger emissions per km for each aircraft size category from Ecoinvent.
| Distance (km) | Aircraft Size | Description |
|---|---|---|
| 0 - 800 | very_short | Regional/domestic flights |
| 800 - 1,500 | short | Short-haul flights |
| 1,500 - 4,000 | medium | Medium-haul flights |
| 4,000+ | long | Long-haul intercontinental flights |
Calculation Details
Calculation Details
Business travel flight emissions are calculated as:CO₂e = Distance (km) × Emission Factor (kg CO₂e/passenger-km) × Trip MultiplierWhere:
- Distance: Calculated from IATA codes or provided directly
- Emission Factor: Based on aircraft size category (from Ecoinvent)
- Trip Multiplier: 2x for round trips, 1x for one-way
Ground Transportation (Car & Rail)
Car Travel Emission Factors
Car Travel Emission Factors
For car travel (business travel and commuting), emission factors depend on:
- Vehicle size: small, medium, large
- Fuel type: diesel, petrol, electric, hybrid, LPG, natural gas
Rail Travel Emission Factors
Rail Travel Emission Factors
For rail travel, emission factors depend on:
- Origin location (regional grid factors for electric trains)
- Renewable energy (yes, no, don’t know)
Employee Commuting
Emission Factor Sources
Emission Factor Sources
Ecoinvent 3.8+ Cut-off
- Lifecycle emission factors by transport mode
- Regional variations where available
- Covers cars, public transit, and active transport
- Well-to-Wheel (WTW) factors including fuel production
Distance Calculation
Distance Calculation
When origin/destination are provided, distance is calculated using routing services. If geocoding fails or locations are unavailable, use
total_km directly.Calculation Details
Calculation Details
Employee commuting emissions are calculated as:CO₂e = Distance (km) × Days × Daily_Trips × Emission Factor × 2 (round trip)Where:
- Distance: One-way distance from home to office
- Days: Number of working days in the period (based on
weekly_travels) - Daily_Trips: Number of trips per day (default: 1)
- Emission Factor: Based on transport type from Ecoinvent
carpool: true, the result is divided by 3 (average carpool occupancy).Example (Car commute, 5 days/week):Freight Transportation
Freight Emission Factors
Freight Emission Factors
For freight transportation, emission factors depend on:
- Transport mode: road, rail, sea, air
- Vehicle type: truck size, ship type, aircraft type
- Load factor: weight transported in tonnes
- Fuel consumption per tonne-km
- Vehicle efficiency
- Empty return trips (where applicable)
Transport Mode Comparison
Transport Mode Comparison
Typical emission factors by transport mode (kg CO₂e per tonne-km):
These are indicative ranges; actual factors depend on specific vehicle types and routes.
| Mode | EF Range | Notes |
|---|---|---|
| Air | 0.5 - 1.0 | Highest emissions, fastest |
| Road | 0.05 - 0.15 | Varies by truck size |
| Rail | 0.02 - 0.05 | Low emissions for bulk |
| Sea | 0.01 - 0.03 | Lowest per tonne-km |

