Sea Freight: GLEC
Calculate sea freight emissions with the Global Logistics Emissions Council (GLEC) framework, which factors in fuel consumption, ship operational practices and auxiliary activities at ports.
Updated for GLEC v3.2 (2025)
One emission factor was revised (international container vessels, energy scope calculation). Vessel categories, distance tiers and well-to-wheel multipliers are unchanged.
Sample requests
Send the first body for a quote before booking. Once the booking is final, send it again with audit set to true.
{
"expand": ["items"],
"items": [{
"audit": false,
"type": "sea_freight",
"external_reference": "test_2",
"origin": "OSL",
"destination": "HEL",
"weight_in_tonnes": 86,
"fuel_type": "vlsfo",
"vessel_type": "liquefied_gas_tanker_under_199999_dwt",
"load_characteristic": "heavy",
"energy_scope": "ttw",
"methodology": "GLEC"
}]
}audit_for is optional
Pass the ID of an auditable entity when you calculate on behalf of that entity. Otherwise, leave it out.
Defaults
When a field is missing, SQUAKE fills it in before calculating.
| Field | Default | Applies when |
|---|---|---|
vessel_type | general_cargo_under_4999_dwt | No vessel_type is sent |
fuel_type | hfo | No fuel_type is sent |
energy_scope | wtw | No energy_scope is sent |
Request fields
typestringrequiredsea_freight
methodologystringrequiredGLEC
originstringSQUAKE tries to resolve any format. Ideally, use the Post standard for addresses, UN/LOCODE for ports (DEHAM), or latitude and longitude (+40.712,-74.006).
destinationstringSame formats as origin.
distance_in_kmnumberTakes priority over origin and destination. Without it, SQUAKE resolves the distance from them.
weight_in_tonnesnumberCargo weight in tonnes.
vessel_typeenumGLEC defaults to general_cargo_under_4999_dwt. Values are bulk_carrier_under_9999_dwt, bulk_carrier_under_34999_dwt, bulk_carrier_under_59999_dwt, bulk_carrier_under_99999_dwt, bulk_carrier_under_199999_dwt, bulk_carrier_above_200000_dwt, chemical_tanker_under_4999_dwt, chemical_tanker_under_9999_dwt, chemical_tanker_under_19999_dwt, chemical_tanker_under_39999_dwt, chemical_tanker_above_40000_dwt, general_cargo_under_4999_dwt, general_cargo_under_9999_dwt, general_cargo_under_19999_dwt, general_cargo_above_20000_dwt, liquefied_gas_tanker_under_49999_dwt, liquefied_gas_tanker_under_99999_dwt, liquefied_gas_tanker_under_199999_dwt, liquefied_gas_tanker_above_200000_dwt, oil_tanker_under_4999_dwt, oil_tanker_under_9999_dwt, oil_tanker_under_19999_dwt, oil_tanker_under_59999_dwt, oil_tanker_under_79999_dwt, oil_tanker_under_119999_dwt, oil_tanker_under_199999_dwt, oil_tanker_above_200000_dwt, other_liquids_tankers_under_999_dwt, other_liquids_tankers_above_1000_dwt, ferry_ropax_under_1999_dwt, ferry_ropax_under_4999_dwt, ferry_ropax_under_9999_dwt, ferry_ropax_under_19999_dwt, ferry_ropax_above_20000_dwt, refrigerated_bulk_under_1999_dwt, refrigerated_bulk_under_5999_dwt, refrigerated_bulk_under_9999_dwt or refrigerated_bulk_above_10000_dwt. See the mapping of vessel_type to fuel_type.
energy_scopeenumttw or wtw. Defaults to wtw.
fuel_typeenumhfo, vlsfo or mdo. Defaults to hfo. See the mapping of vessel_type to fuel_type.
external_referencestringYour identifier for the item, up to 128 characters, so you can match results to requests. SQUAKE doesn't guarantee the order of items.
auditbooleanSet to true to create immutable audit records for finalised calculations. Must be enabled for your account.
POST /v2/calculations in the API referenceSample response
{
"carbon_quantity": 713817,
"carbon_unit": "gram",
"items": [{
"carbon_quantity": 713817,
"carbon_unit": "gram",
"external_reference": "test_2",
"type": "sea_freight",
"methodology": "GLEC",
"distance": 883.0,
"distance_unit": "kilometer",
"algorithm_specifics": {
"algorithm_type": "glec",
"data": {
"co2e_in_g": 713817,
"co2e_emissions_wtw_in_g": 835318,
"co2e_per_tonne_km_in_g": 9,
"tonne_km": 75938,
"reporting_year": 2024,
"transportation_mode": "sea_transportation"
}
}
}]
}Bibliography
Smart Freight Centre helped us fine-tune our calculations of all freight and logistics operations in line with the GLEC framework.
- Smart Freight Centre (2025). Global Logistics Emissions Council Framework V3.2.
- Towards efficient and zero emissions. Smart Freight Centre. smartfreightcentre.org