Energy leveller

US energy autonomy leaves climate threat intact

The International Energy Agency’s latest global forecast suggests booming production from gas and oil-rich shales could make the United States self-sufficient by 2035. The geopolitical implications would be far-reaching. Yet, the buzz about US energy autonomy masks a broader challenge. Gas may present a cleaner, reassuring profile. But if the IEA’s forecasts are right, the window for fighting destructive climate change is narrowing.

Whatever the global balance of energy power, the IEA continues to expect a long-term global temperature increase of 3.6 degrees Celsius, relative to pre-industrial levels, without more aggressive action to cut carbon emissions. Factoring in only modest progress in emissions reduction schemes, the IEA estimates that global carbon output will rise from a record 31.2 giga-tonnes in 2011 to 37 giga-tonnes by 2035. That’s a slower rate of growth than the previous decade, due to cleaner-burning gas and renewables in the global energy mix. But it’s still an increase over last year’s record emissions levels.

To stand a better-than-even chance of limiting the global temperature increase to two degrees — the level climate scientists think would avoid the most severe effects of climate change - the IEA says carbon emissions would have to fall to just over 22 giga-tonnes by 2035.

Two decades might seem like plenty of time for unexpected advances in clean energy technology to help lower emissions without the need for more aggressive action. But the timeframe is deceptive. New power plants take years to build and keep running for decades once they become operational. The IEA estimates that some 81 per cent of the allowable emissions in the two-degree temperature rise scenario is already locked into existing infrastructure today. By 2017, that percentage will be 100 per cent. This means that any new capacity added thereafter would have to be carbon free to prevent a higher temperature increase — which isn’t realistic.

The US energy boom and accompanying production of cleaner-burning natural gas may be a boon to the US economy, with big implications for global trade flows and energy security. But it does little to alter this challenging picture.