IEA Global Methane Tracker 2023 · CCGT electricity generation
Gas supply origin determines how close its lifecycle emissions are to coal
Total lifecycle gCO₂e per kWh of electricity from a 50%-efficient CCGT plant.
Combustion CO₂ is fixed at ~390 g/kWh regardless of gas origin.
Upstream fugitive methane is entirely determined by supply country —
and is beyond the importer's regulatory reach once supply contracts are signed.
METHANE TIMEFRAME:CH₄ = 82.5× CO₂ (IPCC AR6)
Combustion CO₂ (~390 g/kWh — same everywhere)
Upstream fugitive CH₄ as CO₂e · GWP20 = 82.5
Coal combustion reference (~820 g/kWh)
Norway
Nigeria / Algeria
Why the choice of timeframe matters for 2030–2050 targets
Methane stays in the atmosphere for ~12 years — far shorter than CO₂ (centuries).
Over a 100-year horizon (GWP100 = 28), its warming effect is averaged across
decades of decay, making leaked methane look relatively modest.
Over a 20-year horizon (GWP20 = 82.5), you capture the full near-term
warming punch — the warming that happens between now and ~2045. For actors with commitments
centred on 2030–2050 net-zero pathways, the 20-year metric is the more policy-honest framing.
It is also why importing gas from high-leakage countries with no enforceable methane standards
can eliminate the climate advantage over coal during exactly the window that matters most.
Toggle between GWP20 and GWP100 above to see the difference.
Data Sources & Methodology
Country methane intensity figures (Norway, USA, Russia, Angola, Algeria, Nigeria):
DBI Gastechnologisches Institut / German Federal Ministry for Economic Affairs & Climate Action (BMWK),
"Analyses of Methane Emissions in the Natural Gas Sector" (2024) — drawing directly from:
IEA Global Methane Tracker 2023 Data Explorer
(CC BY 4.0).
Full IEA tracker report:
IEA Global Methane Tracker 2025.
Qatar methane intensity: Estimated from IEA Middle East regional benchmarks.
The IEA describes Qatar and Gulf producers as below the global average but does not publish
a single precise national figure. Treat with appropriate caution.
GWP values: IPCC Sixth Assessment Report (AR6), Working Group I, Table 7.SM.7 —
GWP20 = 82.5, GWP100 = 28 for fossil methane (including climate-carbon feedbacks).
IPCC AR6 WGI (2021).
Coal lifecycle emissions reference: ~820 gCO₂/kWh — IPCC AR5 median lifecycle
estimate for subcritical coal. Upstream coal mining methane is not included here
(conservative assumption that favours gas in the comparison).
CCGT combustion CO₂: ~390 gCO₂/kWh(e) at 50% LHV efficiency, consistent with
standard engineering values for modern combined-cycle gas turbines.
Emission factors used in this chart
Country
Methane intensity (%)
Source
Notes
Norway
0.01%
IEA / DBI (2024)
Qatar
0.30%
IEA regional estimate
Estimated *
United States
1.00%
IEA / DBI (2024)
Likely understated vs Alvarez et al. (2018, Science) which measured ~1.7–2%
Russia
1.40%
IEA / DBI (2024)
Angola
1.70%
IEA / DBI (2024)
Algeria
2.30%
IEA / DBI (2024)
Nigeria
2.30%
IEA / DBI (2024)
GWP20 (CH₄)
82.5×
IPCC AR6 (2021)
20-year global warming potential
GWP100 (CH₄)
28×
IPCC AR6 (2021)
100-year global warming potential
Coal reference
820 g/kWh
IPCC AR5
Combustion only, subcritical coal
CCGT combustion
390 g/kWh
Engineering standard
50% LHV efficiency
Disclosure: This chart was generated with assistance from
Claude Sonnet 4.6 (Anthropic, 2025). The underlying emission factors,
GWP values, and source data are drawn from the primary references listed above.
IEA intensity figures are inventory-based and may underestimate actual emissions,
particularly for countries without independent monitoring programmes.
This visualisation is provided for informational purposes; readers are encouraged
to consult the primary sources linked above before drawing policy conclusions.