ExxonMobil closes Mossmorran plastics plant in Scotland: comment

ExxonMobil has closed its Mossmorran ethylene plant in Scotland two weeks earlier than expected.

Profile picture of George Smeeton

By George Smeeton

info@eciu.net

Share

Commenting on the news that ExxonMobil has closed its Mossmorran ethylene plant in Scotland two weeks earlier than expected [1] Jess Ralston, Energy Analyst at the Energy and Climate Intelligence Unit (ECIU), said: "The closure of Mossmorran will be devastating for the workers and nearby communities that have been so used to it being an integral part of the local economy. It will be a worrying time for many thinking about the future of Fife.

"The chemicals sector has been in long term decline for many decades; geologically, oil and gas production in the North Sea is declining which reduces feedstock for plants like Mossmorran, and ageing infrastructure combined with high gas prices have been a lethal combination for the sector.

"The UK Government is bringing in more policy and network cost relief for heavy industries soon, but it has been criticised for narrow eligibility, plus the fundamental problem of these industries being reliant on volatile gas prices remains."

Laura Anderson, Senior Associate at the Energy and Climate Intelligence Unit (ECIU) said: “The closure of Mossmorran will be deeply worrying news for workers, their families, and the wider Fife community, which has relied on the plant for decades. Sudden industrial closures have real human consequences, and those affected deserve support and clear plans for what comes next.

"While today’s focus is rightly on jobs, it’s also important to recognise that the chemicals and refining sectors have faced mounting pressures for years. Declining North Sea output means less domestic feedstock, ageing infrastructure is increasingly costly to maintain, and exposure to volatile and often high gas prices has left UK plants at a competitive disadvantage. These are structural challenges that long pre-date current climate policy.

"Government support to reduce energy and network costs for heavy industry is welcome, but concerns remain about how many firms will actually qualify and whether it can shield businesses from the underlying instability of gas-dependent production. This underlines the need for a serious, long-term strategy to help industrial regions attract new investment and good jobs in growing, lower-carbon sectors, so communities like those around Mossmorran have a secure future, not repeated cycles of uncertainty.”

A background briefing on Mossmorran is below; it is available to download here. 


Background briefing: Mossmorran

Overview

  • ExxonMobil has closed the Fife Ethylene Plant (FEP) at Mossmorran earlier than scheduled due to economic pressures. (STV, 2026)
  • The closure results in around 430 direct job losses, but impacts will be much wider in the supply chains throughout Fife and Scotland. (STV, 2026)
  • ExxonMobil cited the UK’s economic and policy environment, high supply costs, and ageing, inefficient infrastructure as driving the decision (Chemical Engineer, 2025)
  • Although they are separate plants owned by different organisations, Mossmorran is linked to Grangemouth by pipeline infrastructure:
    • Geological decline in North Sea oil and gas output since the 1990s has impacted the infrastructure of the UK chemicals sector, and decline at different plants during the different chemical production stages has had further impacts downstream.
    • Essentially, Mossmorran takes the chemical feedstock ethane, derived from gas imported from multiple sources to the St Fergus gas terminal, and heats it (“cracking”) to create ethylene.
    • Ethylene is piped to Grangemouth and used to make plastics and many other chemicals.  

Structural and economic context


Long‑term decline

  • Scottish heavy industry has faced prolonged uncertainty, predating the fossil fuel crisis.
  • The shutdowns at Grangemouth refinery (ceased operations in 2025) and Mossmorran (ended production in 2026) reflect decades of accumulated structural weaknesses, not just recent market turbulence or “carbon taxes”.
  • Petroineos, a joint venture between PetroChina and INEOS at Grangemouth reported losses of nearly £400,000 per day in 2024, though financial difficulties stretch back to 2011, showing that instability long preceded the energy crisis. (The Scotsman, 2024) (Scottish Government, 2024)
  • Mossmorran similarly struggled to remain economically viable as costs and inefficiencies accumulated.

Ageing infrastructure

Market & geopolitical pressures


Volatile gas prices and energy costs

  • Volatile global oil and gas prices, which are key inputs for chemicals and refining, have strained industry margins since the fossil fuel crisis, intensifying the challenges at Mossmorran and Grangemouth.

Brexit

Declining North Sea feedstock

Local and national industrial impacts of closure


Employment and supply chain effects

  • Direct employment impacts include roughly 180 ExxonMobil staff and 200–250 contractors, alongside apprenticeships ending early. (STV, 2026)
  • Broader supply chain and community impacts are expected, with unions describing the closure as devastating for Fife. (Unite, 2026).

Part of a wider European decline


ENDS

Notes to editors:

1. STV: https://news.stv.tv/scotland/exxonmobils-mossmorran-plastics-plant-closes-weeks-early-with-400-jobs-at-risk 

2. The background briefing on Mossmorran is available to download here. 

For more information or for interview requests:

George Smeeton, Head of Communications, ECIU, Tel: 07517 407687, email: george.smeeton@eciu.net