In-depth: BP data reveals record CO2 emissions in 2018 driven by surging use of gas

Last year saw record levels of CO2 emissions, gas and oil use, and installations of renewable energy, according to new global data from oil giant BP.

Gas was the largest driver of energy-use growth in 2018, responsible for more than 40% of the increase. This, along with increased use of oil and coal, led to global CO2 emissions rising by 2% in 2018, the largest year-on-year increase in seven years.

Renewable energy sources were the largest source of new electricity generation worldwide for the third year in a row, driven primarily by the growth of wind and solar generation. Wind and solar grew at their second fastest rate on record, driven by growth in China, though the growth in wind and solar generation in the US, EU, and India was slower in 2018 than in 2017.

However, there is a constantly growing gap between today’s energy use and what would be needed to meet the goals of the Paris Agreement, given that emissions must, according to scientists, reach net-zero by mid-century to avoid dangerous levels of global warming.

Here Carbon Brief runs through the 2019 BP Statistical Review of World Energy, examining how energy use, electricity generation and CO2 emissions have changed across different energy sources and regions of the world.

Gas leads large increase in energy use

Energy use grew in 2018 at a rate of 2.9%, the largest growth since 2010. China, the US and India accounted for more than two-thirds of global energy-use growth, with US energy use expanding at the fastest rate for 30 years.

Energy use increased by 390m tonnes of oil equivalent (Mtoe) in 2018. Fossil fuels were responsible for 71% of this, while near-zero-carbon energy sources, including solar, wind, hydro and nuclear, were responsible for 29%.

The figure below shows the change in energy use between 2017 and 2018 for each major energy fuel type.

Changes in the sources of global energy supply between 2017 and 2018, millions of tonnes of oil equivalent. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

Natural gas represented the single largest contributor to global energy-use growth in 2018, increasing by 5.3% compared to 2017. It alone was responsible for 40% of the increase in total energy use.

Non-hydro renewables grew by 14.5% in 2018. This was the largest relative growth of any energy source, though it was still below the record growth experienced in 2017. Non-hydro renewables now represent 4% of global energy use, with all zero-carbon sources representing 15% of global energy.

Oil consumption grew by 1.5% in 2018, with China and the US contributing around 85% of the growth in oil use. This growth was primarily concentrated in the transportation sector, reflecting increased vehicle ownership and miles driven.

Coal consumption grew by 1.4% in 2018, the fastest growth since 2013. This reverses a three-year period where coal either grew very little or actually declined, though global coal use still remains below its 2013 peak (see below for more).

Hydro generation grew by 3% in 2018, similar to growth rates seen over the past decade. While small compared to other generation sources, nuclear generation rose by 2.4% in 2018. China was responsible for around 75% of the global growth in nuclear generation.

CO2 grows at fastest pace in 7 years

The BP report estimates that global CO2 emissions grew by 2.0% in 2018, the fastest growth for seven years. This is identical to the latest estimate by the Global Carbon Project (GCP), though is lower than GCP’s originally reported forecast of 2.7% in late 2018. This follows a 1.7% increase in 2017, dimming any hopes that global CO2 emissions were peaking.

The figure below shows global CO2 emissions broken down by country on the left, as well as year-over-year changes on the right. The black line on the right figure shows total global annual CO2 emissions changes, while changes in each individual country are shown by coloured bars.

Above: Global energy-related CO2 emissions between 1965 and 2018, broken down by key countries and regions, millions of tonnes of CO2. Below: Annual changes over the past five years, millions of tonnes of CO2. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

China, India and the US were responsible for around 69% of the global increase in CO2, with China being the single largest contributor. Chinese CO2 emissions grew by 2.2% in 2018, Indian emissions grew by 7% and US emissions grew by 2.6%.

The US reversed a three-year trend of CO2 reductions, posting its largest increase in emissions since 2013, though there are indications that this increase might be something of an anomaly.

EU emissions declined in 2018, falling 2% from 2017 levels, marking the first time in three years that EU emissions have declined.

Modest declines in fossil-fuel share

Falling coal use in previous years had helped offset CO2 emissions from rising use of gas and oil. However, coal use has risen in the last few years, while oil has steadily grown and gas use has accelerated.

Over the past decade – since 2009 – global coal use has increased by 10%, oil use has increased by 14% and natural-gas use has increased by a massive 31%. The figure below shows annual global energy use in million tonnes of oil equivalent (Mtoe) by fuel, along with the total share coming from fossil fuels.

Top panel: Global energy use by source between 1965 and 2018, millions of tonnes of oil equivalent (Mtoe). Lower panels: Fossil fuels’ share of the global energy mix over the same period, %. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

Non-hydro renewables are the fastest-growing energy source, increasing 14.5% last year and 290% over the past decade. However, they are still a relatively small part of total energy use, which continues to be dominated by fossil fuels.

Nonetheless, the share of energy coming from fossil fuels in 2018 – 85% – is the lowest since the BP dataset begins in 1965.

Non-hydro renewables are also on-track to produce more energy than nuclear in 2019.

India once again leads coal expansion

Global coal consumption increased by 1.4% in 2018, its fastest growth since 2013. India was the largest single driver of coal growth, responsible for around 45% of the global increase. China was another large contributor – at 20%.

The figure below shows global coal use – in Mtoe – on the left, along with annual changes on the right. Total annual changes are shown by the black line, while coloured bars show each country’s contribution.

Above: Global coal use between 1965 and 2018, broken down by key countries and regions, millions of tonnes of oil equivalent. Below: Annual changes over the past five years, millions of tonnes of oil equivalent. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

Coal use notably declined in both the EU and US, though declines were smaller than in some prior years. Overall, demand for coal in OECD countries fell to its lowest level since 1975. Coal’s overall share in primary energy has continued to decline, falling to 27% on the back of expanded natural gas and renewable generation.

Despite the large expansion of coal in India in both 2017 and 2018, there are some signs that growth might not continue indefinitely. The pipeline of new coal plants shrunk by more than a quarter over the past year – and more than five-fold since 2014. In many parts of India renewables are less expensive than coal generation and forecasts of future electricity demand have been revised downward, leading to an ongoing debate about how much new coal will actually be built.

Last year saw China reverse four years of reductions – or near-zero growth – in coal use, with an increase of around 1% from 2017.

Renewables largest share of new electricity

Global electricity generation rose by 3.7%, with about half of the growth coming from China and much of the remainder from India and the US.

Electricity from renewable sources – including wind, solar, and hydro – were the single largest contributor to the increase in global electricity use, representing a third of the total growth. This is the third year in a row where renewables have been the largest contributor to global electricity growth. Renewables set a new growth record – of 442 terawatt-hours (TWh) – in 2018. The bulk of this – 314 TWh – came from grown of non-hydro renewables, primarily wind and solar.

The figure below shows global electricity generation by fuel source, along with the portion of electricity coming from fossil fuels.

Top panel: Global electricity use by source between 1965 and 2018, terawatt hours. Lower panels: Fossil fuels’ share of the global electricity mix over the same period, %. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

Coal was the second largest contributor to increased electricity generation in 2018, representing 31% of total growth. Despite overall coal consumption being lower than its 2013 peak, electricity generated from coal set a new record in 2018. This reflects the increased generation efficiency of new coal plants built in recent years.

Natural gas was the third largest contributor, at 25% of the growth. The much larger contribution of natural gas to total energy-use growth reflects the fact that a large portion of natural gas is used for non-electric purposes, such as space heating or industrial processes, while a substantial majority of coal is used to generate electricity.

The share of non-hydro renewables used in electricity generation increase from 8.4% in 2017 to 9.3% in 2018. Low carbon sources – nuclear, hydro, and non-hydro renewables – collectively contributed 36% of global electricity generation, the highest since 1990.

Coal still accounts for the largest share of power generation at 38%, with natural gas the second largest at 23%.

The 2019 BP report increased its estimates of coal use for electricity generation for the year 2017 by around 1% compared to the 2018 report, though prior year values were largely unchanged.

Wind and solar growth slows modestly

Wind and solar energy collectively grew by 17% in 2018, a bit below the 2017 growth rate of 23%. Total growth of energy production from wind and solar was 62Mtoe in 2018 compared to 67 in 2017. This is not the first time that growth has slowed between years – it last happened in 2014 – but it is a somewhat unusual occurrence.

Solar generation grew by 30Mtoe, while wind grew by 32Mtoe. Solar has become an increasingly large part of non-hydro renewables, providing more than 40% of renewables growth in 2018.

The figure below shows global combined wind and solar energy generation – in Mtoe – on the left, along with annual changes on the right. Total annual changes are shown by the black line, while coloured bars show each country’s contribution.

Above: Global wind and solar use between 1965 and 2017, broken down by key countries and regions, millions of tonnes of oil equivalent. Below: Annual changes over the past five years, millions of tonnes of oil equivalent. Source: BP Statistical Review of World Energy 2019 and Carbon Brief analysis. Chart by Carbon Brief using Highcharts.

Last year saw China surpass the EU in as the region of the world with the most generation from solar and wind. While Chinese solar and wind generation accelerated in 2018, the US, India, and the EU all saw declines in the growth of wind and solar generation compared to 2017.