Short answer: Conventional natural gas is nonrenewable.
It takes millions of years to form underground. Once reserves are depleted, they cannot be replaced on a human timescale. According to the International Energy Agency (IEA, 2023), proven global reserves could last about 50 years at current consumption rates.
But there’s another story: Renewable Natural Gas (RNG). Produced from food scraps, farm waste, and landfill emissions, RNG creates usable methane in months rather than millennia. As long as organic waste exists, RNG can be replenished.
How Long Will Supplies Last?
Global supply is finite. Updated figures from EIA and IEA (2023–2024) show:
- Global reserves: ~190 trillion cubic meters, equivalent to ~50 years of supply.
- U.S. shale reserves: Abundant, but heavily dependent on fracking.
- Middle East (Qatar, Iran): Control over 40% of global supply.
- Europe and Asia: Largely dependent on imports, vulnerable to price and geopolitical risks.
The timeline is shrinking. Rising demand in Asia and the war in Ukraine have accelerated depletion and forced nations to rethink reliance on gas.
Lifecycle Emissions: The Full Picture
Natural gas has often been branded as “cleaner than coal.” That’s only partially true.
Lifecycle analysis (extraction → processing → transport → combustion) shows:
- CO₂ emissions from combustion: ~400–500 g CO₂ per kWh (about 50% less than coal).
- Methane leakage: Even a 2–3% leak rate during production can erase climate advantages. Methane is 84x more powerful than CO₂ over 20 years and 28–34x stronger over 100 years.
- Fracking: Intensifies methane leakage and contaminates water supplies.
Bottom line: The “cleaner” label is misleading when leaks and upstream impacts are factored in.
