Natural Gas and the Energy Transition: Bridge Fuel or Dead End?

Few topics in the energy transition start as many arguments as natural gas. Burned for electricity, it emits roughly half the CO₂ of coal, and its flexibility helps balance wind and solar. It is also a fossil fuel. Its main component, methane, is a potent greenhouse gas that leaks along the supply chain, and the 2021–2023 price crisis showed how exposed gas-dependent economies are. Here is what gas does today, how clean it really is, and where demand is heading.

Gas in the global energy system

Natural gas supplied about 41,300 TWh of primary energy in 2024, according to the Energy Institute Statistical Review / Our World in Data. That is roughly 23% of world primary energy, behind oil (~31%) and close to coal (~26%). Consumption has risen steadily from about 24,000 TWh in 2000.

Shares are indicative ranges based on IEA balances. In electricity, gas generated about 6,920 TWh in 2025, 21.8% of the world total (Ember / OWID), second only to coal at 33%.

The country pages and the explorer have the full picture.

How clean is gas? CO₂ at the stack

Methane has more hydrogen per carbon atom than coal or oil, so burning it releases less CO₂ per unit of energy.

The methane problem

Methane (CH₄) traps far more heat than CO₂ in the short term: its global warming potential is about 82 over 20 years (GWP20) and 30 over 100 years (GWP100) for fossil methane (IPCC AR6). So even small leakage rates matter:

At 2% leakage on a 20-year horizon, a modern gas plant’s warming impact rises from ~350 to ~590 g CO₂e/kWh. That is still below coal (whose mines also leak methane), but the gap is much smaller. Studies suggest gas loses its short-term climate advantage over coal above roughly 3% leakage.

Leak estimates vary widely by country and operator. Alvarez et al. (Science, 2018) put US supply-chain leakage at about 2.3% of production, some 60% higher than the official inventory. Aerial and satellite surveys of the Permian basin have found higher rates. The best operators in Norway stay well under 0.1%. The IEA’s Global Methane Tracker estimates that oil and gas operations release roughly 80 Mt of methane a year, and that around 40% could be avoided at no net cost because the captured gas can be sold.

LNG and the 2022 shock

For decades pipeline gas dominated regional markets. Liquefied natural gas (LNG), cooled to −162 °C and shipped by tanker, now ties them into a global market. Liquefaction, shipping and regasification use about 10–15% of the gas’s energy and add upstream emissions, so LNG’s life-cycle footprint is typically 10–20% higher than that of pipeline gas.

When Russian pipeline supplies to Europe collapsed in 2022, European wholesale prices spiked above €300/MWh in August 2022 (TTF) versus a pre-crisis norm of €15–25/MWh. Electricity prices followed, because gas plants often set the marginal price. What happened next:

• EU gas demand fell around 15–20% versus the 2017–2021 average through efficiency, fuel switching, mild weather and industrial curtailment.
• LNG imports surged, with the US becoming the largest LNG exporter.
• Heat pump sales and solar installations accelerated sharply in 2022–2023.

Prices settled at €30–50/MWh in 2024–2025, still roughly double pre-crisis levels. New LNG export capacity from the US and Qatar coming online in 2025–2028 is expected to loosen markets.

Gas as a “bridge fuel”

In some countries the bridge argument holds up well. The UK cut coal from ~40% of electricity in 2012 to zero in 2024, with gas and wind replacing it; power-sector emissions more than halved. In the US, coal-to-gas switching was the largest single driver of power-sector CO₂ declines from 2005 to 2020.

But a bridge has to lead somewhere. Gas infrastructure lasts 30–50 years, so new plants, pipelines and LNG terminals risk becoming stranded assets or locking in emissions. The IEA’s Net Zero Emissions scenario requires no new long-lead-time gas fields beyond those already approved in 2021, with global gas use falling by more than half by 2040.

Gas in electricity: from baseload to backup

As wind and solar grow, gas plants run fewer hours. They still earn their keep as flexible capacity, above all during multi-day lulls (“Dunkelflaute”) and demand peaks. Germany’s gas fleet, for example, now works mainly as a flexible partner to wind and solar. Low-carbon backup could come from:

• Batteries (hours) and pumped hydro (hours to days); see Energy Storage Technologies Compared;
• Interconnectors and demand response;
• Gas plants with carbon capture, or burning biomethane or hydrogen;
• Firm low-carbon sources: hydro, nuclear, geothermal.

Gas in buildings: the heat pump question

Gas boilers heat around 40% of European homes and most homes in the UK, Netherlands and Italy. A condensing boiler at 90% efficiency emits about 225 g CO₂/kWh of heat (202 g/kWh of gas combustion), before methane leakage. A heat pump with SPF 3.2 on the 2025 European average grid (~250–280 g/kWh) emits around 80–90 g/kWh of heat. Running costs depend on the ratio of gas to electricity prices. Compare yours in the heat pump vs gas boiler calculator or the full heating cost comparison.

Worked example: converting your gas bill

A household reads 1,450 m³ of gas on its meter over a year. With a calorific value of 39.5 MJ/m³ and a volume correction of 1.02264 (UK convention):

At 90% boiler efficiency, that gives about 14,600 kWh of useful heat. A heat pump with SPF 3.2 would supply the same heat from ~4,570 kWh of electricity. Convert your own readings with the gas unit converter.

Industry and feedstock

Industry uses gas for high-temperature heat (glass, ceramics, chemicals) and as feedstock for ammonia and methanol. Industrial heat pumps can now supply more and more of the low- and medium-temperature heat up to ~200 °C. Higher temperatures need electric furnaces, hydrogen, biomass or carbon capture. Ammonia production runs on grey hydrogen made from gas, which makes it one of the first targets for green hydrogen (see Green Hydrogen Explained).

Biomethane and renewable gas

Upgraded biogas (biomethane) can go into the gas grid and burn in the same appliances. Europe produced roughly 4–5 billion m³ of biomethane in 2023–2024, against EU demand of about 330 billion m³. Even the REPowerEU target of 35 bcm by 2030 would cover only around a tenth of current use. Biomethane is useful, but feedstock limits how much there can be. See Bioenergy and Biogas Explained.

What drives gas prices

Unlike oil, gas has historically been priced regionally, and prices still differ widely between continents:

(1 MMBtu ≈ 0.293 MWh.) Add network charges, taxes, supplier margins and levies, and household prices typically come to two to four times the wholesale price. Gas-fired plants often set the marginal price in European electricity markets, so gas prices feed straight into electricity bills. That was the main reason electricity prices spiked in 2022.

Risks to watch:

• Storage and weather. Europe goes into each winter relying on storage filled over the summer. A cold, windless winter can drain it fast.
• LNG supply waves. Large new liquefaction capacity in the US and Qatar could push prices down in the late 2020s.
• Carbon pricing. From 2027–2028 the EU’s new ETS2 will put a carbon price on gas used for heating in buildings and road transport, adding roughly €0.01–0.02/kWh at the initially expected price levels.

Track country-by-country gas dependence on the explorer, and convert between m³, MMBtu, therms and kWh with the energy unit converter.

Bottom line

Where natural gas pushed out coal, it did real good for the climate, and it still matters for grid flexibility and industry. Its climate advantage holds only if methane leakage stays well below 1%, though, and its role will shrink as heat pumps, renewables and storage take over the jobs it does today. For households, the real question is not whether gas is “clean” but when switching to electric heating pays off. Explore the numbers in the heat pump vs gas boiler calculator and see each country’s gas dependence on the world energy map.

Figures in this guide are typical ranges drawn from the sources above; your own numbers depend on location, prices and equipment. Use the linked calculators for site-specific estimates.