The Scottish Government has committed to ending the practice of landfilling biodegradable municipal waste (BMW) by 2025, in line with recommendations from the Climate Change Committee (CCC). The waste sector accounts for approximately 4% of Scotland’s greenhouse gas (GHG) emissions, with the degradation of biodegradable waste to landfill accounting for a large proportion of the waste treatment sector’s GHG emissions.

The CCC also recommended the ban be extended to include all biodegradable waste generated from non-municipal sources. The Scottish Government has agreed to this, subject to consultation.

The Scottish Government is working with local authorities to secure alternative treatment options for wastes encompassed by the ban. There is a need for effective delivery planning to ensure that residual waste treatment capacity matches the waste supply. This assessment considers the national residual waste capacity requirements to inform such delivery planning.

Key findings

The research models three scenarios.

• A baseline/ ‘business as usual’ scenario (Scenario 1) results in a large gap in current and planned treatment capacity to deliver the BMW landfill ban (0.61 Mt) in 2025. This is exacerbated under the extended biodegradable non-municipal wastes (BNMW) landfill ban (0.66 Mt) as more material is required to be diverted from landfill to alternative treatment facilities.
• Under an approaching targets scenario (Scenario 2), there is still an estimated capacity gap in 2025 under the BMW landfill ban (0.13 Mt), which increases (to 0.18 Mt) under the extended BNMW waste landfill ban.
• In the scenario where all policy targets are achieved (Scenario 3), there is an estimated overcapacity due to the high impact of waste reduction measures on total waste requiring management. This results in a surplus treatment capacity (-0.48 Mt) in 2025 for the materials within the scope of the BMW landfill ban. This surplus treatment capacity reduces slightly (-0.43 Mt) under the extended BNMW landfill ban.

Carbon modelling

Carbon modelling of the scenarios shows that the most significant reduction in carbon emissions results from increased contributions to waste reduction and recycling. As extra efforts are made to divert materials from becoming waste in the first place, and with increased recycling, Scenario 3 results in the greatest carbon savings.