Frequently asked questions about GLEC and Dcycle

This document covers the most frequently asked questions about logistics emission calculations with GLEC v3 and the Dcycle platform. It serves as a reference for teams involved in measuring logistics carbon footprints and Lean & Green plans.

Base methodology

Dcycle implements the GLEC Framework v3 (Global Logistics Emissions Council), the international standard for logistics emissions and the framework recognised by Lean & Green (AECOC / EvoKE).

Base GLEC formula:

tCO₂e = Load (t) × Distance (km) × TOC emission factor (tCO₂e/tkm)

• Load (t): Actual kg of the shipment (or estimated with load_factor)
• Distance (km): km of the leg assigned to that customer/shipment
• TOC factor: Fixed value by vehicle type, published by GLEC

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Q1 — Do GLEC factors change based on the vehicle’s load percentage?

No. GLEC emission factors (in gCO₂e/tkm) are fixed by operation type (TOC). GLEC publishes a single average value per vehicle category, which already incorporates empty running (the typical % of km run empty in the sector).

Framework	Does the factor vary with load %?
GLEC	No. Fixed factor per TOC.
DEFRA	Yes: average laden, 50% laden, full laden…

Actual load is reflected in GLEC through the actual weight of the shipment. If you enter real kg, tkm are correct and emissions are proportional to weight.

Example — Rigid truck 26–32t Euro 6 (factor = 0.162 kgCO₂e/tkm):

Load	Distance	tkm	Emissions
5,000 kg	203 km	1,015	164.4 kgCO₂e
2,500 kg	203 km	507.5	82.2 kgCO₂e

The factor does not change. Emissions fall because there is less load.

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Q2 — Can the base year be recalculated if we change the calculation method?

Technically yes, to maintain methodological comparability. But before doing so, verify:

• If the base year is linked to a formal commitment (Lean & Green, SBTi…), it may require validation from the certifying body.
• Any methodological change must be applied to all years (base + monitoring).
• If the new calculation yields a lower base year, the reduction target also becomes more demanding.

Recommendation: Consult AECOC / Lean & Green before any base-year recalculation.

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Q3 — How are km assigned per leg and per customer in the data file?

Each line in the file represents a (leg × customer) pair. The distance_km field is assigned in full to each customer receiving goods on that leg — it is not summed across lines or prorated.

Example:

Movement MOV-001, leg LEG-A → 203.3 km, 4 customers:

Customer	Load	Distance assigned
Customer A	5,490.79 kg	203.3 km
Customer B	256.08 kg	203.3 km
Customer C	109.35 kg	203.3 km
Customer D	89.04 kg	203.3 km

If the same truck continues to leg LEG-B (13.6 km) and Customer A also appears there: Total km attributed to Customer A = 203.3 + 13.6 = 216.9 km

This is consistent with GLEC: the distance assigned is that of the actual journey made for that specific delivery.

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Q4 — What is the load_factor for and when should it be used?

The load_factor is an estimated load fraction for when you do not know the actual kg.

Effective load (kg) = declared_weight (kg) × load_factor

Situation	Use load_factor?
You have actual shipment kg	No. Enter kg directly. load_factor = 1.
You only have pallets/units, no kg	Yes. Apply the estimated occupancy %.
You want to adjust a previous estimate	Yes. To correct the declared weight.

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Q5 — Why does the intensity KPI not change when I modify the load?

This is mathematically correct. Test example:

	Test 1	Test 2
Effective load	1 kg × 0.1 = 0.1 kg	300 kg × 0.8 = 240 kg
Total tkm	753.94	226,180.99
Total kgCO₂e	129.48	38,842.89
KPI (kgCO₂/tkm)	0.1717	0.1717

The mathematical demonstration:

KPI = tCO₂e / tkm
    = [load × km × TOC_EF] / [load × km]
    = TOC_EF  ← load and km cancel out

The intensity KPI always equals the average emission factor of the vehicles used. Absolute emissions are very different (129 kg vs 38,842 kg), but the ratio is the same because the same vehicles perform the same type of operation.

The only way to move the intensity KPI is to use vehicles with a lower emission factor (different TOC category or alternative fuel).

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Q6 — Does improving data quality reduce emissions?

Improving data quality is a precision lever, not a reduction lever.

Previous situation	When switching to actual kg	Effect
You were overestimating kg	Actual kg are lower	Calculated emissions fall
You were underestimating kg	Actual kg are higher	Calculated emissions rise
Estimate was accurate	No significant difference	No change

The value of improving data quality lies in credibility and auditability (Lean & Green, CSRD, customers) and in having a real basis for operational decisions.

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Q7 — Route optimisation and load consolidation: does their impact appear in Lean & Green?

The question: “Route optimisation was one of our Lean & Green plan objectives. But if the intensity KPI only improves when we change the vehicle, how do we measure the impact of optimising routes or consolidating loads?”

Answer

The confusion comes from using the wrong KPI to measure these actions. There are two KPIs with completely different purposes:

Intensity KPI (tCO₂e/tkm) → measures vehicle efficiency. It only improves by changing the vehicle type or fuel. When you optimise routes and reduce km, this ratio does not change because tkm and tCO₂e fall in the same proportion.

Absolute emissions (total tCO₂e) → measures total real impact. This is the KPI Lean & Green uses for compliance with the reduction commitment (Star 1 = -20% in 5 years, Star 2 = -40%).

The tCO₂e/tkm will not improve with these actions — but that is not the Lean & Green compliance KPI.

Example — route optimisation (−15% km)

	Without optimisation	With −15% km
Trips	100	100
km/trip	200 km	170 km
Total tkm	200,000	170,000
Total tCO₂e	X	0.85X (−15%)
KPI tCO₂e/tkm	0.162	0.162 (unchanged)

Absolute emissions fall by 15% — exactly what Lean & Green tracks for the target.

Example — load consolidation (eliminating trips)

	Without consolidation	With consolidation
Trips	10 of 5 t, 200 km	5 of 10 t, 200 km
Total km	2,000 km	1,000 km
Total tCO₂e	Y	0.5Y (−50%)

The key to consolidation is not fitting more kg into the same trip — it is making fewer trips to move the same amount of goods.

Which KPI to use for each lever?

Lever	Total tCO₂e	tCO₂e/tkm	tCO₂e/delivery	tCO₂e/t delivered
Change TOC / efficient vehicle	↓	↓	↓	↓
Alternative fuel	↓	↓	↓	↓
Route optimisation	↓	→	↓	↓
Load consolidation	↓	→	↓	depends
Eliminate empty running	↓	↓	↓	↓

Recommended KPIs for Lean & Green tracking in Dcycle

1. Total tCO₂e — Lean & Green commitment compliance
2. tCO₂e per delivery made — captures consolidation and route efficiency
3. tCO₂e per tonne delivered — captures load efficiency
4. Total annual km — direct indicator of route optimisation
5. tCO₂e/tkm — fleet efficiency (only improves with TOC or fuel changes)

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How route optimisation impact appears in a Lean & Green plan

The most common point of confusion

Companies with an active Lean & Green plan typically have three types of reduction measures: fleet renewal, operational improvements (duo-trailer, backhauling…), and route optimisation. When they find that changing load or km does not move the intensity KPI, they conclude that route optimisation “does not work”. That conclusion is wrong — it comes from looking at the wrong indicator.

The two indicators and what moves each

Intensity KPI (kgCO₂e/tkm)

This is the vehicle’s footprint: how much it emits per tonne moved one kilometre. It is fixed by vehicle type (TOC). It only improves if you change the vehicle or fuel. Analogy: it is a car’s fuel consumption per 100 km — it does not change based on how much weight you carry or how short the trip is. It only changes if you change the engine.

Absolute emissions (tCO₂e/year)

This is the total annual impact. This falls with route optimisation, load consolidation, and trip elimination. And this is the Lean & Green compliance KPI (Star 1 = -20% in 5 years, measured as % reduction in relative emissions vs. base year).

How route optimisation works within a Lean & Green plan

In GLEC methodology, optimising routes means reducing km travelled to deliver the same amount of goods. This translates directly into fewer total tkm and fewer absolute emissions.

tkm avoided by optimisation × TOC factor = kgCO₂e saved

Example with a reference logistics company (base 293M tkm, Euro 5 fleet):

Year	tkm avoided	kgCO₂e saved	% of total plan
Year 2	2,355,022	449,809	8%
Year 3	4,710,045	899,618	7%
Year 5	11,775,114	2,249,046	17%

The intensity KPI (kgCO₂e/tkm) does not change because the vehicle type is the same. The saving is visible in absolute emissions — which is what Lean & Green counts.

Real levers in a Lean & Green plan and their relative weight

In a typical plan for a logistics operator with diesel vehicles:

Lever	% reduction contributed	KPI it moves
Fleet renewal (Euro 6, HVO, EV)	75–85% of total	Intensity KPI + absolute emissions
High-capacity vehicles (duo-trailer)	5–10%	Absolute emissions
Route optimisation	8–17%	Absolute emissions

Fleet renewal is always the main driver. Route optimisation is a valid complementary lever with real impact — but visible only in absolute emissions.

How to track route optimisation in Dcycle

KPI	How to calculate it	What it indicates
tkm per tonne delivered	Total tkm / total tonnes for period	If it falls, routes are more efficient
Average km per leg	Mean of distance_km by service type	If it falls, routes are shorter
Total tCO₂e	Sum of emissions for period	The Lean & Green compliance KPI
Shipments per tonne	Total movements / total tonnes	If it falls, there is more consolidation

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Glossary

Term	Definition
GLEC	Global Logistics Emissions Council. Framework for calculating carbon footprint in transport.
TOC	Transport Operation Category. Classification of vehicle type with its emission factor.
WTW	Well-to-Wheel. GLEC factors include the full chain: fuel production + combustion.
tkm	Tonne-kilometres. Unit of transport work = load (t) × distance (km).
tCO₂e	Tonnes of CO₂ equivalent. Includes CO₂, CH₄, and N₂O.
load_factor	Load factor. Fraction (0–1) to estimate actual load when exact kg are unknown.
Intensity KPI	tCO₂e/tkm. Vehicle efficiency. Only improves with better TOC or fuel.
Absolute KPI	Total tCO₂e. Total impact. Improves with any reduction in activity or efficiency.
Empty running	% of km the vehicle travels empty. Already incorporated in GLEC average factors.
Lean & Green	Logistics sustainability certification. Star 1 = -20% emissions in 5 years. Uses GLEC methodology.