The share of electricity in Great Britain generated from burning coal and gas fell to a record-low 2.4% earlier this month, Carbon Brief analysis shows.
The record low was reached at lunchtime on Monday 15 April and lasted for one hour. There have been a record 75 half-hour periods in 2024 to date when fossil fuels met less than 5% of demand.
There were only five such periods during the whole of 2022 – and just 16 last year.
The findings show that National Grid Electricity System Operator (NGESO) is closing in on its target of running the country’s electricity network without fossil fuels, for short periods, by 2025.
NGESO is “confident” this target will be met, its director of system operations tells Carbon Brief, adding that achieving the goal will be “absolutely groundbreaking and pretty much world leading”.
However, Carbon Brief’s analysis also illustrates some of the challenges to meeting the government’s target of a fully decarbonised electricity grid by 2035.
Fossil fuels fall
The island of Great Britain, comprising England, Scotland and Wales, has its own independent electricity system, which is managed at the transmission level by NGESO.
The transmission grid is effectively the motorway network for electricity.
It links large-scale electricity suppliers such as coal, gas and nuclear power plants to centres of demand, in towns and cities around the country.
Other companies run the low-voltage “distribution” networks, which take power from the transmission grid and distribute it to individual homes and businesses.
For most of its existence, this system had remained largely unchanged for decades. More recently, it has been in the midst of a rapid transformation as part of national efforts to reduce emissions.
In 2009, some 74% of GB electricity was coming from fossil fuels and only 2% was from renewables.
By 2023, there were several thousand large renewable sites dotted around the country, as well as nearly 1.5m small solar installations on the roofs of homes, offices and warehouses.
Only a third of GB electricity in 2023 came from fossil fuels – with 40% from renewables.
Yet these annual figures disguise even greater changes in the month-to-month, day-to-day, hour-to-hour and second-by-second operation of the electricity system.
The figure below shows the share of electricity in Great Britain being generated by fossil fuels in each half-hour period since 2009, including the record-low of 2.4% earlier this month.
The figure above shows how unprecedented it is for fossil fuels to be meeting such low shares of demand on the GB grid.
Indeed, the lowest half-hourly fossil fuel share in 2009 was 53% and, as recently as 2018, it had never dipped below 10%. The first half-hour period with less than 5% fossil fuels only came in 2022, when there were five such periods in total across the year.
During 2023, there were just 16 half-hour periods with less than 5% fossil fuels – the majority of which came during December of that year.
In contrast, there have already been 75 half-hours with less than 5% fossil fuels in 2024 to date.
The shift to ever lower fossil fuel use is illustrated in the figure below, which shows daily average shares starting to regularly drop below 10% in December 2023 and April 2024.
The daily average fossil fuel share fell to a record low of 6.4% on 5 April 2024, with the average on 15 April 2024 standing at 7.0%. Until 2022, the daily average had never been below 10%.
‘Zero-carbon operation’
Carbon Brief’s analysis shows that NGESO is closing in on the target, first set in 2019, of being able to operate the grid with “zero carbon”, for short periods, by 2025.
(NGESO defines this target as being able to run the GB transmission grid without fossil fuels. It bases its goal on a metric of 100% “zero-carbon operation”, meaning the share of demand, excluding imports, being met by renewables connected to the transmission grid or nuclear. It says this metric reached a peak of 90% during two half-hour periods in January and March 2023.)
The first-ever period of at least 30 minutes of “zero carbon operation” is most likely to come in autumn 2025, Craig Dyke, NGESO director of system operations tells Carbon Brief. “We’re confident that we will have the right capabilities on the system to be able to do that,” he adds.
Dyke says this moment will be “absolutely groundbreaking and pretty much world leading”, particularly given the size of the GB economy and the fact that, as an island, its grid is relatively isolated from neighbouring countries.
There have been two separate challenges in reaching this target. The first is having enough low-carbon electricity supplies to be able to cover demand during a given half-hour period.
The second challenge is having the technical capability to keep the grid stable without fossil fuels.
These technical requirements include maintaining the frequency of electricity supplies at close to 50Hz and responding to rapid changes in supply and demand through operational reserves.
NGESO also maintains the ability to restart the grid in the case of a total shutdown, sometimes referred to as “black start”, but now more formally called “restoration”.
Increases in wind and solar capacity mean low-carbon sources are now already sufficient to meet 100% of electricity demand in some periods. However, on the technical side, the 2025 target has been a “significant engineering challenge”, Dyke says:
“Getting to the 2025 ambition has been a significant engineering challenge, which we are solving.”
Grid services have, historically, been provided by fossil fuel power plants. Over the past five years, however, NGESO has been changing the way it procures these services, as well as reforming the rules of grid operation and the way it balances the grid in real time.
For example, through its “pathfinder” projects NGESO has contracted a series of sites that can offer grid services without fossil fuels. These include “synchronous condensers”, effectively giant spinning turbines that provide grid stability without burning fossil fuels.
Other key innovations include the use of batteries to manage the frequency of the grid and “grid forming inverters”, which use sophisticated power electronics to offer different types of grid support.
This development means renewable projects will be able to contribute grid stability services, such as “inertia”, that have traditionally only been offered by conventional fossil fuel generators.
Dyke tells Carbon Brief:
“This hasn’t just happened overnight. It’s been a culmination of a significant amount of effort over a number of years. That’s not just us [NGESO] operating in isolation, that’s planning and collaboration with industry, with [energy regulator] Ofgem and with the government…It’s not just about technologies, it’s about hearts and minds and processes and systems and people working together.”
Fully decarbonised grid
For NGESO, the 2025 goal is a stepping stone on the way to being able to run the grid at zero carbon constantly by 2035, in line with the government target of “fully decarbonised” electricity.
(The opposition Labour party is targeting a decarbonised grid by 2030. This target is seen as incredibly ambitious – and possibly even “unachievable” overall. A spokesperson for NGESO tells Carbon Brief: “Our previously published scenarios shows it is achievable – although challenging.”)
There are several further technical challenges to meeting this 2035 goal.
For example, the rise of variable wind and solar has expanded the ups and downs of fossil fuels in the mix, illustrated by the range between peaks and troughs in the first figure, above.
This is illustrated further in the simplified figure, below, by the increasing gap between the highest and lowest fossil fuel shares seen in each year (upper and lower blue lines, respectively).
The figure below also shows the annual average fossil fuel share of electricity (dashed line) falling from 74% in 2009 to 26% in 2024 to date. (The small increase in this annual average in 2022 was due to the GB grid exporting gas-fired power to France, where much of the nuclear fleet was offline.)
Notably, the maximum fossil fuel share in each half-hour period has declined more slowly than the average or minimum figures, falling from 88% in 2009 to 72% in 2023 and 66% in 2024 to date.
This reflects the fact that the GB grid still relies on gas-fired power stations being able to switch on when the wind is not blowing and the sun is not shining.
Crucially, the nation will need low-carbon alternatives to this gas capacity in order to reach the government’s target of a fully decarbonised grid by 2035.
These alternatives will need to operate across a range of different timescales, from seconds through to weeks and even years. For within-day timescales, this is likely to mean expanding energy storage capacity, principally with batteries, but also pumped hydro or compressed air.
For periods of weeks or seasons, the options include ongoing reliance on unabated gas – which would be incompatible with carbon targets – or the use of hydrogen turbines or gas plants that are coupled with carbon capture and storage (CCS).
The post Analysis: Fossil fuels fall to record-low 2.4% of British electricity appeared first on Carbon Brief.
Analysis: Fossil fuels fall to record-low 2.4% of British electricity
Drought and heatwaves occurring together – known as “compound” events – have “surged” across the world since the early 2000s, a new study shows.
Compound drought and heat events (CDHEs) can have devastating effects, creating the ideal conditions for intense wildfires, such as Australia’s “Black Summer” of 2019-20 where bushfires burned 24m hectares and killed 33 people.
The research, published in Science Advances, finds that the increase in CDHEs is predominantly being driven by events that start with a heatwave.
The global area affected by such “heatwave-led” compound events has more than doubled between 1980-2001 and 2002-23, the study says.
The rapid increase in these events over the last 23 years cannot be explained solely by global warming, the authors note.
Since the late 1990s, feedbacks between the land and the atmosphere have become stronger, making heatwaves more likely to trigger drought conditions, they explain.
One of the study authors tells Carbon Brief that societies must pay greater attention to compound events, which can “cause severe impacts on ecosystems, agriculture and society”.
Compound events
CDHEs are extreme weather events where drought and heatwave conditions occur simultaneously – or shortly after each other – in the same region.
These events are often triggered by large-scale weather patterns, such as “blocking” highs, which can produce “prolonged” hot and dry conditions, according to the study.
Prof Sang-Wook Yeh is one of the study authors and a professor at the Ewha Womans University in South Korea. He tells Carbon Brief:
“When heatwaves and droughts occur together, the two hazards reinforce each other through land-atmosphere interactions. This amplifies surface heating and soil moisture deficits, making compound events more intense and damaging than single hazards.”
CDHEs can begin with either a heatwave or a drought.
The sequence of these extremes is important, the study says, as they have different drivers and impacts.
For example, in a CDHE where the heatwave was the precursor, increased direct sunshine causes more moisture loss from soils and plants, leading to a drought.
Conversely, in an event where the drought was the precursor, the lack of soil moisture means that less of the sun’s energy goes into evaporation and more goes into warming the Earth’s surface. This produces favourable conditions for heatwaves.
The study shows that the majority of CDHEs globally start out as a drought.
In recent years, there has been increasing focus on these events due to the devastating impact they have on agriculture, ecosystems and public health.
In Russia in the summer of 2010, a compound drought-heatwave event – and the associated wildfires – caused the death of nearly 55,000 people, the study notes.
The record-breaking Pacific north-west “heat dome” in 2021 triggered extreme drought conditions that caused “significant declines” in wheat yields, as well as in barley, canola and fruit production in British Columbia and Alberta, Canada, says the study.
Increasing events
To assess how CDHEs are changing, the researchers use daily reanalysis data to identify droughts and heatwaves events. (Reanalysis data combines past observations with climate models to create a historical climate record.) Then, using an algorithm, they analyse how these events overlap in both time and space.
The study covers the period from 1980 to 2023 and the world’s land surface, excluding polar regions where CDHEs are rare.
The research finds that the area of land affected by CDHEs has “increased substantially” since the early 2000s.
Heatwave-led events have been the main contributor to this increase, the study says, with their spatial extent rising 110% between 1980-2001 and 2002-23, compared to a 59% increase for drought-led events.
The map below shows the global distribution of CDHEs over 1980-2023. The charts show the percentage of the land surface affected by a heatwave-led CDHE (red) or a drought-led CDHE (yellow) in a given year (left) and relative increase in each CDHE type (right).
The study finds that CDHEs have occurred most frequently in northern South America, the southern US, eastern Europe, central Africa and south Asia.
Threshold passed
The authors explain that the increase in heatwave-led CDHEs is related to rising global temperatures, but that this does not tell the whole story.
In the earlier 22-year period of 1980-2001, the study finds that the spatial extent of heatwave-led CDHEs rises by 1.6% per 1C of global temperature rise. For the more-recent period of 2022-23, this increases “nearly eightfold” to 13.1%.
The change suggests that the rapid increase in the heatwave-led CDHEs occurred after the global average temperature “surpasse[d] a certain temperature threshold”, the paper says.
This threshold is an absolute global average temperature of 14.3C, the authors estimate (based on an 11-year average), which the world passed around the year 2000.
Investigating the recent surge in heatwave-leading CDHEs further, the researchers find a “regime shift” in land-atmosphere dynamics “toward a persistently intensified state after the late 1990s”.
In other words, the way that drier soils drive higher surface temperatures, and vice versa, is becoming stronger, resulting in more heatwave-led compound events.
Daily data
The research has some advantages over other previous studies, Yeh says. For instance, the new work uses daily estimations of CDHEs, compared to monthly data used in past research. This is “important for capturing the detailed occurrence” of these events, says Yeh.
He adds that another advantage of their study is that it distinguishes the sequence of droughts and heatwaves, which allows them to “better understand the differences” in the characteristics of CDHEs.
Dr Meryem Tanarhte is a climate scientist at the University Hassan II in Morocco, and Dr Ruth Cerezo Mota is a climatologist and a researcher at the National Autonomous University of Mexico. Both scientists, who were not involved in the study, agree that the daily estimations give a clearer picture of how CDHEs are changing.
Cerezo-Mota adds that another major contribution of the study is its global focus. She tells Carbon Brief that in some regions, such as Mexico and Africa, there is a lack of studies on CDHEs:
“Not because the events do not occur, but perhaps because [these regions] do not have all the data or the expertise to do so.”
However, she notes that the reanalysis data used by the study does have limitations with how it represents rainfall in some parts of the world.
Compound impacts
The study notes that if CDHEs continue to intensify – particularly events where heatwaves are the precursors – they could drive declining crop productivity, increased wildfire frequency and severe public health crises.
These impacts could be “much more rapid and severe as global warming continues”, Yeh tells Carbon Brief.
Tanarhte notes that these events can be forecasted up to 10 days ahead in many regions. Furthermore, she says, the strongest impacts can be prevented “through preparedness and adaptation”, including through “water management for agriculture, heatwave mitigation measures and wildfire mitigation”.
The study recommends reassessing current risk management strategies for these compound events. It also suggests incorporating the sequences of drought and heatwaves into compound event analysis frameworks “to enhance climate risk management”.
Cerezo-Mota says that it is clear that the world needs to be prepared for the increased occurrence of these events. She tells Carbon Brief:
“These [risk assessments and strategies] need to be carried out at the local level to understand the complexities of each region.”
The post Heatwaves driving recent ‘surge’ in compound drought and heat extremes appeared first on Carbon Brief.
Heatwaves driving recent ‘surge’ in compound drought and heat extremes
Greenhouse Gases
DeBriefed 6 March 2026: Iran energy crisis | China climate plan | Bristol’s ‘pioneering’ wind turbine
Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Energy crisis
ENERGY SPIKE: US-Israeli attacks on Iran and subsequent counterattacks across the Middle East have sent energy prices “soaring”, according to Reuters. The newswire reported that the region “accounts for just under a third of global oil production and almost a fifth of gas”. The Guardian noted that shipping traffic through the strait of Hormuz, which normally ferries 20% of the world’s oil, “all but ground to a halt”. The Financial Times reported that attacks by Iran on Middle East energy facilities – notably in Qatar – triggered the “biggest rise in gas prices since Russia’s full-scale invasion of Ukraine”.
‘RISK’ AND ‘BENEFITS’: Bloomberg reported on increases in diesel prices in Europe and the US, speculating that rising fuel costs could be “a risk for president Donald Trump”. US gas producers are “poised to benefit from the big disruption in global supply”, according to CNBC. Indian government sources told the Economic Times that Russia is prepared to “fulfil India’s energy demands”. China Daily quoted experts who said “China’s energy security remains fundamentally unshaken”, thanks to “emergency stockpiles and a wide array of import channels”.
‘ESSENTIAL’ RENEWABLES: Energy analysts said governments should cut their fossil-fuel reliance by investing in renewables, “rather than just seeking non-Gulf oil and gas suppliers”, reported Climate Home News. This message was echoed by UK business secretary Peter Kyle, who said “doubling down on renewables” was “essential” amid “regional instability”, according to the Daily Telegraph.
China’s climate plan
PEAK COAL?: China has set out its next “five-year plan” at the annual “two sessions” meeting of the National People’s Congress, including its climate strategy out to 2030, according to the Hong Kong-based South China Morning Post. The plan called for China to cut its carbon emissions per unit of gross domestic product (GDP) by 17% from 2026 to 2030, which “may allow for continued increase in emissions given the rate of GDP growth”, reported Reuters. The newswire added that the plan also had targets to reach peak coal in the next five years and replace 30m tonnes per year of coal with renewables.
ACTIVE YET PRUDENT: Bloomberg described the new plan as “cautious”, stating that it “frustrat[es] hopes for tighter policy that would drive the nation to peak carbon emissions well before president Xi Jinping’s 2030 deadline”. Carbon Brief has just published an in-depth analysis of the plan. China Daily reported that the strategy “highlights measures to promote the climate targets of peaking carbon dioxide emissions before 2030”, which China said it would work towards “actively yet prudently”.
Around the world
- EU RULES: The European Commission has proposed new “made in Europe” rules to support domestic low-carbon industries, “