A new report published in Science suggests that switching from diesel to natural gas in trucks could increase greenhouse gas emissions. The study runs counter to the policies highlighted in President Obama’s State of the Union speech extolling the benefits of increased natural gas production.
Burning natural gas releases about half as much carbon dioxide as burning coal. But methane, a component of natural gas, often leaks out of pipes and wells, negating its climate benefits when burned.
The new study analyzes 20 years of data and says the EPA has underestimated methane leakage, but concludes that burning natural gas is still better than burning coal.
The report questions the shift if leaks aren’t contained. Burning diesel is cleaner than burning coal, but the savings from burning natural gas in trucks don’t offset the increased methane levels from leaks.
The study found that most of the leaks come from a few pieces of faulty equipment. But the amount of methane leaked from fracking operations is controversial.