Analysis: UK carbon emissions in 2017 fell to levels last seen in 1890

§ Sources of reductions

UK CO2 emissions have been decreasing steadily every year since 2012, with particularly large drops in 2014 and 2016. This decline continued in 2017, driven by a combination of declining coal use and natural gas use. Oil and petroleum use has increased slightly, though not enough to offset the declines in CO2 associated with other fuels.

The causes of the declines in emissions between each year from 2012 to 2017 are shown in the figure below. The black bars represent estimated change in annual emissions based on fossil fuel consumption, while the red, blue and grey bars show the contribution of oil, natural gas and coal, respectively, to the annual change.

While the fall in coal use in 2017 was much smaller than that in 2016, it is clear that the large decline in coal use in recent years was not a temporary phenomenon. Coal now accounts for only 5.3% of total primary energy consumed in the UK, down from 22% in 1995. The UK government has pledged to close all coal-fired power stations by 2025.

The slight decrease in natural gas use in 2017 was largely related to a milder winter and does not show up in temperature-adjusted versions of the BEIS data that try to normalise for year-over-year changes in weather condition.

Reductions in coal use has driven most of the carbon reductions in recent years, though reductions in gas use were a larger driver earlier in the decade. The figure below shows how much each fuel has contributed to the overall decline in total CO2 emissions from fossil fuels since 2009.

Coal use in the UK had been mostly steady from the late 1990s until 2014 (see later coal chart), with declines in gas and oil use driving most emissions reductions. However, coal use fell precipitously between 2014 and 2017, declining by nearly 75% compared to 2013 values. Coal’s fall in recent years is responsible for the bulk of CO2 reductions in the UK over the past decade.

Based on the preliminary BEIS numbers, Carbon Brief estimates that oil and petroleum use accounted for approximately 49% of total UK CO2 emissions from fossil fuels in 2017, up from 37% in 2010. The increased fraction of emissions coming from oil is due to declines in emissions from coal, as total emissions from oil has actually slightly declined, from 196MtCO2 to 191MtCO2 between 2010 and 2017.

The transportation sector consumed approximately 77% of all oil in 2015, the latest year where detailed breakdowns of consumption by sector are available. This means that approximately 38% of total UK CO2 emissions from fossil fuels can be attributed to oil consumed in the transportation sector in 2017, up from 36% in 2016. (This number may differ slightly from the official BEIS estimate once that is released, as Carbon Brief’s number only includes CO2 emissions from fossil fuels rather than from all sources.)

§ Coal continues long slide downward

The UK’s coal consumption has fallen every year since 2012. It is now well below any level of use in the country’s recent history. The figure below shows UK coal consumption between 1858 and 2017.

Back in 1858, the UK’s coal use was around 65m tonnes. It grew to a peak of 221m tonnes in 1956, then started a long decline. In 2017, coal use is estimated to be a mere 15m tonnes, 78% below its 1858 value and a massive 93% below its peak in 1956.

§ CO2 emissions down to below 1890 levels

With coal quickly disappearing in the UK and other fossil fuel use mostly flat, emissions have continued their steady decline. Overall, CO2 emissions have declined faster in the UK since the early 1990s than in almost any other large economy. Outside the miner strikes in 1893 and 1921 and the 1926 general strike, emissions are now as low as they were back in the year 1890, as shown in the figure below.

While these rapid declines are impressive, there is still a long way to go to meet the national target of 80% reductions below 1990 levels by 2050. CO2 emissions currently are around 38% below 1990 levels, leaving additional reductions of 250 Mt CO2 – around 68% of today’s emissions – to achieve over the next three decades.

If non-CO2 greenhouse gases are taken into account, emissions have fallen by around 42% since 1990. This assumes that non-CO2 greenhouse gases remained at 2016 levels for 2017, as 2017’s non-CO2 emissions data is not yet available.

§ Carbon Brief calculations

UK CO2 emissions for fossil fuels were estimated by multiplying the reported consumption of each fuel by its respective emission factor, accounting when possible for different uses of a particular fuel across industries or applications. Carbon Brief’s estimates of UK CO2 emissions in 2017 are based on analysis of provisional UK energy use data published by BEIS. The same approach has been generally accurate in estimated year-to-year changes in emissions over the past seven years (see table, below). Note that both the Carbon Brief and reported values shown exclude emissions from land-use changes.

The resulting estimate of carbon emissions from fossil fuels using this approach may differ slightly from official greenhouse gas inventories due to different sectors included and assumed emission factors. However, the results are generally within 1% to 3% of total reported non-land-use CO2 emissions for prior years.

Update: Note that this analysis using the latest government data is unable to calculate the UK’s “imported” emissions. Carbon Brief covered this topic last year and found: “Even though domestic emissions have fallen 27% in the UK between 1990 and 2014, once CO2 imports from trade are considered this drops to only an 11% reduction.”

Update 19/3/2018: Note that this article focuses on CO2 emissions from fossil fuel combustion and uses an approach similar to that employed by BEIS in calculating official UK CO2 emissions. As such, it ignores the emissions associated with biomass energy, which are disputed. Woody biomass has replaced roughly a sixth of the coal that has been eliminated in the UK since 2012.