Carbon, Cost and Speed: Teaching Logistics Trade-offs Through Live Simulation

Logistics accounts for approximately 8% of global greenhouse gas emissions, and the sector is under increasing regulatory and consumer pressure to decarbonise. For business and supply chain students, understanding that pressure is straightforward. Understanding how to navigate it — how to cut emissions without destroying service levels or collapsing margins — is the genuine graduate skill, and it is one that classroom instruction alone cannot build.

The Three-Way Tension That Defines Modern Logistics

Every logistics decision sits inside a triangle of competing priorities: carbon impact, cost efficiency, and delivery speed. Consolidating shipments to reduce emissions adds lead time. Switching to electric vehicles reduces carbon but increases capital cost and constrains range. Air freight is fast but emits roughly 50 times more CO2 per tonne-kilometre than sea freight. Students who understand these numbers in theory often freeze when asked to make the actual call — because the right answer depends on context, customer requirements, and commercial constraints that no textbook can fully specify.

“Transport and logistics contribute approximately 8% of global greenhouse gas emissions. Road freight alone accounts for nearly half of that figure, making last-mile and middle-mile optimisation critical sustainability levers.”

— International Transport Forum, 2023

Why Sustainability Cannot Be an Add-On Module

A growing number of logistics programmes have responded to sustainability pressure by adding a standalone module on green logistics or circular supply chains. This is better than nothing, but it risks creating a cognitive separation between sustainability and core operational decisions. The most capable logistics professionals do not treat carbon as a separate consideration — they factor it into every carrier selection, every inventory policy, every network design decision. Teaching that integration requires learning environments where the carbon score is visible alongside the cost and service-level scores, not confined to a separate assessment.

How SPPIN Sim Tracks the Carbon-Cost-Speed Triangle

SPPIN Sim tracks all 17 UN SDGs live during every simulation session, with SDG 13 (Climate Action) and SDG 12 (Responsible Consumption and Production) updating in real time as teams make logistics decisions. A team that consistently prioritises speed will watch its carbon score deteriorate and its sustainability KPI fall behind competitors who have found the trade-off balance. The live leaderboard makes that consequence visible and competitive — exactly the motivational structure needed to make sustainability a genuine decision variable rather than a theoretical obligation.

Designing Sessions That Force the Conversation

• Start with a baseline round where teams optimise purely for cost — then reveal the carbon score and ask them to justify it
• Introduce a regulatory event mid-session — a new carbon tax or emissions cap — and require teams to revise their logistics strategy without abandoning their commercial targets
• Use the sustainability leaderboard as the primary ranking in the final round, shifting the competitive frame from profit to responsible performance
• Debrief by asking each team to articulate the trade-off they made and whether they would make the same choice in a real operating context

Preparing Graduates for Scope 3 Accountability

Scope 3 emissions — those generated by a company's value chain rather than its own operations — are becoming a mandatory reporting item for large organisations under both UK and EU disclosure frameworks. Logistics is one of the largest Scope 3 categories for most product businesses. Graduates who have practised making carrier and routing decisions with carbon visibility are far better placed to contribute to their employer's Scope 3 reduction strategy than those who encountered sustainability only in an essay. That is a tangible graduate readiness differentiator — and one that CILT's sustainability domain explicitly validates.