CHARTS: US Carbon Emissions Are Dropping

One of the next big items on President Obama’s green agenda is a new set of caps on greenhouse gas emissions from power plants. Set to roll out over the next few years, the rules aim to slash the climate impact of the nation’s biggest polluters. But statistics released yesterday from the federal Energy Information Administration show that even without these new caps, energy-related carbon emissions—those that come from powering factories, homes, cars, and businesses—dropped almost four percent between 2011 and 2012, marking the fifth out of the last seven years for these emissions to decline:

total carbon emissions


Overall energy consumption fell by 2.4 percent last year, even as the GDP grew by 2.8 percent. That translates to a 5.1 percent drop in energy use per dollar of GDP. In other words, businesses are finding that they can use less energy (and/or cleaner sources of it) and stay productive. In the chart below, carbon intensity refers to the carbon emissions per dollar of GDP; energy intensity is energy use per dollar of GDP (the 5.1 percent drop just mentioned). So even as population and per capita output are growing, the amount of electricity use and carbon pollution tied to that growth are dropping:

economic activity


This is great news, but it’s not really new: Here’s another way to look at carbon intensity, which shows how energy efficiency has given us more and more carbon bang for our bucks over the last 60 years:

carbon intensity


So what’s behind last year’s drop? To start, give yourself a pat on the back: Half the cuts came from reductions in household energy use. Ironically, we might have to thank climate change for that, as the biggest reductions came at the start of the year when the US was in the midst of its fourth-warmest winter on record—the EIA’s metric of cold days when heating might be required was down nationwide 19 percent below the 10-year average and 22 percent below 2011. The dark brown line below is 2012; notice how far beneath the other lines it is on the left-hand side: 

residential power


Fuel-efficiency gains for vehicles also played a major role: Even though total miles traveled by cars in the US was the same between 2011 and 2012 (~8 billion miles per day), carbon emissions were down thanks to the growing number of fuel-efficient cars on the road:



Last but not least, the energy we’re still using is coming from cleaner sources—like wind, up almost 20 percent—bringing the overall carbon intensity of electricity generation down by 3.5 percent. The drop in hydro power, EIA analyst Perry Lindstrom said, reflects a return from a particularly high-producing previous year, driven by the amount of water in rivers rather than the construction of new infrastructure, as in the case of wind.

“We’re not building big hydro plants in the US,” he said. “Everything that happens in hydro is driven by precipitation and snowmelt.”

Although 2012 saw severe drought across much of the country, the drought was less pronounced in the Pacific Northwest where the bulk of the country’s hydro plants are, so it’s unclear whether climate might have played a role here as well.

Solar doesn’t appear on the chart because it is lumped in with other sources, including nuclear and geothermal, that saw little change between 2011 and 2012.

But by far the most significant source of reductions came via the substitution of natural gas, made relatively cheap and abundant by fracking, for coal. This chart makes it plain how concerns about fracking, from groundwater contamination to earthquakes to methane emissions, need to be balanced against the massive bite it takes out of much more carbon-intensive coal, although some experts worry that long-term reliance on natural gas could also loosen the market foothold of renewables:

fuel type


More Mother Jones reporting on Climate Desk


Headshot of Editor in Chief of Mother Jones, Clara Jeffery

It sure feels that way to me, and here at Mother Jones, we’ve been thinking a lot about what journalism needs to do differently, and how we can have the biggest impact.

We kept coming back to one word: corruption. Democracy and the rule of law being undermined by those with wealth and power for their own gain. So we're launching an ambitious Mother Jones Corruption Project to do deep, time-intensive reporting on systemic corruption, and asking the MoJo community to help crowdfund it.

We aim to hire, build a team, and give them the time and space needed to understand how we got here and how we might get out. We want to dig into the forces and decisions that have allowed massive conflicts of interest, influence peddling, and win-at-all-costs politics to flourish.

It's unlike anything we've done, and we have seed funding to get started, but we're looking to raise $500,000 from readers by July when we'll be making key budgeting decisions—and the more resources we have by then, the deeper we can dig. If our plan sounds good to you, please help kickstart it with a tax-deductible donation today.

Thanks for reading—whether or not you can pitch in today, or ever, I'm glad you're with us.

Signed by Clara Jeffery

Clara Jeffery, Editor-in-Chief

payment methods

We Recommend