Major polluting companies in the nation have decreased their emission levels, with Galp being the only one that didn't follow suit.
In 2024, the top 10 carbon dioxide (CO2) polluters in Portugal were primarily from the refining, energy, and cement sectors, with the Petrogal – Sines Refinery leading the pack as the largest emitter, followed by TAP (Portugal's national airline) and Cimpor’s Alhandra and Souselas cement plants [1].
Specifically, the Petrogal – Sines Refinery remained the biggest emitter, while TAP rose from third to second place in emissions rank. However, the overall top 10 polluters cut emissions by 11% compared to 2023, primarily due to a decline in CO2 from fossil-fuelled natural gas plants [1].
Galp, which operates refineries including the Sines refinery, increased its emissions by 11% in 2024, indicating a rise in emissions from its refining or energy activities [1]. Cimpor’s Alhandra and Souselas cement plants were the third and fourth biggest emitters, respectively, part of the cement sector’s contribution to CO2 emissions [1].
Other notable entities in the top 10 include Secil – Outão, a cement producer located mid-ranking on the list [1].
The emissions reductions within the top 10 were driven mainly by a decline in CO2 from fossil-fuelled natural gas plants, such as those at Tapada do Outeiro and Pego, attributed to a higher share of renewable energy generation in Portugal's grid [1].
Here's a summary of the top 10 CO2 emitters in 2024:
| Rank | Entity | Sector | 2024 Emissions Trend | |-------|-----------------------------|--------------|-----------------------------| | 1 | Petrogal – Sines Refinery | Refining | Largest emitter | | 2 | TAP | Aviation | Emissions rose; now 2nd | | 3 | Cimpor – Alhandra | Cement | High emissions | | 4 | Cimpor – Souselas | Cement | High emissions | | — | Galp (incl. Sines refinery) | Refining/Energy | Emissions increased by 11% | | ~5-10 | Secil – Outão and others | Cement/Energy | Part of top 10, mixed trends|
No exact quantitative emission values of each entity in metric tons were provided, but the overall sector context and relative rankings are detailed [1].
It's worth noting that there is no indication in the data of TAP reducing emissions; rather, it moved up in rank, suggesting increased emissions or smaller reductions compared to others [1]. Galp’s emissions increase contrasts with the overall reduction trend among the top 10 polluters, highlighting their refinery’s continued emission intensity [1].
There was no further specific breakdown by exact emission tonnage or detailed figures for each entity in the sources. However, the key takeaway is the dominance of Petrogal – Sines Refinery and TAP among the top polluters, with reduction in total emissions led primarily by natural gas power plants shifting toward renewables, and Galp's refinery emissions notably increasing despite some sectoral declines [1].
For more context, the emissions from the three natural gas-fired power plants decreased by 58%, while TAP had a slight increase in emissions of 1%. The refining sector shows a "very significant and growing weight of fossil fuels" in Portugal's economy and polluting emissions [1].
This is the current authoritative picture based on the latest 2024 data reported in 2025 [1].
References: [1] Zero - Zero Waste Portugal (2025). LIFE EFFECT Project Report: Portugal's Top 10 CO2 Emitters in 2024. Retrieved from https://zerowasteeurope.eu/life-effect-project-report-portugals-top-10-co2-emitters-in-2024/ [3] Portuguese Institute of Meteorology (2025). Wildfire Emissions in Portugal 2025. Retrieved from https://www.ipma.pt/pt/sitio/home/noticias/noticias-ambientais/incendios-florestais-em-portugal-2025
- The Petrogal – Sines Refinery, operating within the refining sector, continued to be the largest CO2 emitter in Portugal in 2024.
- Interestingly, TAP, Portugal's national airline, surpassed the Petrogal – Sines Refinery in terms of emissions rank, indicating increased emissions from TAP.
- The cement sector, represented by Cimpor’s Alhandra and Souselas cement plants, also held a significant position in the top 10 CO2 emitters, with Alhandra ranked third and Souselas ranked fourth.
- In contrast to the overall reduction trend among the top 10 polluters, Galp, which operates refineries including the Sines refinery, witnessed an 11% increase in emissions in 2024.
