Climate changing carbon dioxide emissions from industrial sites drop 57% in a decade

• Climate changing carbon dioxide emissions from SEPA regulated industrial sites drop 57% in a decade – down 5% in the last year.
• 2019 Scottish Pollutant Release Inventory (SPRI) contains data from 1,327 regulated sites published by Scottish Environment Protection Agency (SEPA).

The Scottish Pollutant Release Inventory (SPRI) 2019 data – this year experimental official statistics – was published today 29 September 2020 by the Scottish Environment Protection Agency. This year’s data covers annual mass releases of specified pollutants to air and water and information on off-site waste transfers from 1,327 SEPA regulated industrial sites.

Greenhouse gases

The two largest contributing pollutants in terms of emissions are carbon dioxide and methane which drive the overall greenhouse gas trend. 

While carbon dioxide continues to drive the overall emissions trend and remains the largest contributing pollutant in terms of the emissions for 2019, the data shows Scotland’s carbon dioxide emissions have reduced significantly in the last 10 years. Emissions of the gas are down 57 per cent in the decade and 5 per cent annually to around 11,293,146,000 kg since 2018.

Whilst overall carbon dioxide emissions fell by 5% in the last year, direct emissions from those waste and waste-water management sector facilities required to report under SPRI increased by 76% over the last decade, partly driven by a move towards waste incineration instead of landfill for residual waste management. However, their emissions of greenhouses gases remain small relative to the energy sector.

The shift away from landfill towards recycling and incineration has resulted in further reductions in direct Methane emissions. While methane does not remain in the atmosphere as long as carbon dioxide it is initially far more impactful on the climate because of how effectively it absorbs heat. Methane emissions decreased significantly – by 44% – over the decade to 2019, and by 4% between 2018 and 2019 to 26,777,357 kg.

	2010	2018	2019	% change 2010-2019	% change 2018-2019
Carbon dioxide	26,384,456,678	11,849,079,760	11,293,145,941	Down 57%	Down 5%
Methane	47,912,442	27,878,368	26,777,357	Down 44%	Down 4%
Nitrous Oxide	250,912	89,846	96,543	Down 61%	Up 8%
Hydrofluorocarbons	1,465	3,513	1,263	Down 14%	Down 64%
Perfluorocarbons	1,604	4,418	3,945	Up 146%	Up 11%
Sulphur Hexafluoride	207	107	221	Up 7%	Up 106%

All measurements in kilogrammes.

Energy transition

A number of variables influence SPRI emissions. In the long term, the shift away from use of coal as a fuel is a significant factor. Carbon dioxide emissions from the energy sector have fallen by around 70% since 2010, largely due to the closure of coal fired power stations. As emissions from the energy sector have fallen, releases from other sectors now form a greater proportion of the greenhouse gas emissions reported to SPRI.

Some of the decreases observed for these gases can be accounted for by investment in new technologies and renewables, and landfill gas recovery systems.

Wider economic drivers and the weather are other factors identified as affecting carbon dioxide and other greenhouse gas emissions from SPRI sites.

Circular economy

Scotland’s progress towards a circular economy is also highlighted in both SPRI and separate ‘2019 Waste landfilled in Scotland’ and ‘2019 Waste incinerated in Scotland’ Official Statistics released today by SEPA.

As Scotland reduces, reuses and recycles more than ever before, waste which cannot be recycled is now being diverted from landfill as new energy from waste (incineration) infrastructure comes online. As a consequence methane emissions from the waste sector decreased by 47% over the decade, from a high ceiling of 40,868,900 kg in 2010, to 21,575,000 kg in 2019. Capture of gas at landfill sites has also contributed to the reduction. 

Consequently, as methane emissions from landfill have reduced, carbon dioxide from incineration sites have increased 83% over the last decade from a low base of 1,090,000,000 kg to 2,000,000,000 kg in 2019. Emissions from this sector are small compared to that of the energy sector.

These trends represent direct emissions of greenhouse gases from specific parts of the waste management sector. They do not take into account efforts to reduce, reuse and recycle our waste. Scotland’s Carbon Metric shows that in 2018, the overall impact of Scotland’s waste management system – taking into account reduction, recycling, incineration and landfill – was 30% less than in 2011.

Terry A’Hearn, Chief Executive of SEPA, said: “These experimental official statistics chart the progress we’ve made as a nation with our globally ambitious climate change targets, with some pollutants emitted from regulated businesses falling in the last decade.  They also reflect the realism of a modern, Western European economy in transition.

“The successful businesses of tomorrow will be those that are sustainable.  As Scotland’s environmental regulator, our firm focus remains to helping Scottish businesses innovate and emerge stronger and more sustainably from the current public health pandemic, enabling leadership in a decade of climate emergency.”

Minor year-to-year fluctuations in pollutants can often be attributed to changes at a few sites, due to increases or decreases in production, changing source products and new sites opening. All pollutants have a reporting threshold, below which sites do not need to report a value to SPRI. An increase in production can move a site’s releases above the threshold, giving the appearance of a larger increase.