Governors' Wind Energy Coalition

Green California led the country in greenhouse gas emissions between 2011 and 2012, according to an analysis of U.S. EPA’s recently released data.

A wet year in 2011 ramped up hydropower generation in the state, which led to a relative drop in that renewable energy in 2012. The decommissioning of the San Onofre Nuclear Generating Station also raised emissions, said Trevor Houser, a partner with the Rhodium Group and a former climate change adviser in the State Department.

“In much of the country, you had both weaker electricity demand because of weather and less carbon-intensive energy supply because of a switch from coal to natural gas,” Houser said. “The exception was in the West Coast.”

Oregon, Idaho, Wyoming and Colorado’s emissions also rose between 2011 and 2012. About half of the emissions increase in California can be attributed to the San Onofre closure, Houser said.

This one-year increase will not affect California’s target of cutting emissions to 1990 levels by 2020 and further slashing them by 80 percent below 1990 levels by 2050, said James Fine, a senior economist at the Environmental Defense Fund.

“It’s not the trend we’re going to see over time; in fact, it will be the opposite,” he said. The 11.46-million-ton increase over one year represents 3 percent of the number of emissions credits that will be handled in the state’s carbon cap-and-trade system by 2020. This, he believes, will encourage the renewable energy investment to fill the gap left by the San Onofre closure (ClimateWire, June 11).

Natural gas, warmer winters help the Midwest

“California has demonstrated for many years now that we can decouple growth and energy use with growth and price,” he said.

In Ohio, the top greenhouse gas-reducing state, and many of the other states in the Midwest, increased power dispatch by natural gas power plants and an unusually warm winter in 2012 led to lower electricity consumption.

Natural gas became more competitive in wholesale markets because the price of natural gas was lower. The warm weather also decreased residential and commercial demand for natural gas, which helped push down natural gas prices in early 2012 and made the fuel source even more competitive in the power sector.

Delaware experienced a 35.7 percent, or 2.5-million-ton, increase in greenhouse gas emissions, an anomaly on the East Coast. Maryland’s emissions decreased by nearly one-third. But it’s likely that small changes led to these shifts, Houser said.

“In the small states, a couple of changes in facilities can skew the data,” he said. “We’ve been looking more at the tonnage [and not the percentage], mostly to focus on where that national trend that we’ve been seeing for a while was coming from.”

A drop in Ohio’s emissions should also be attributed to the expansion of energy efficiency in the state, said Nolan Moser, director of the energy and clean air programs at the Ohio Environmental Council. The state implemented a 1-percent-per-year energy-saving standard in 2009.

“The standards have been a pretty huge success,” he said.

The factors that led to the decline are transient, and not an reflection of a long-term trend, Houser said. “Greater electricity demand overall, but also greater heating demand, helps push up natural gas prices,” he said. If the coming years have colder winters, coal will recover some of its market share, he said.

Although wind energy was the top source of added capacity in 2012, Houser did not focus on this trend. While the capacity may have led the way, wind did not lead in generation.

“But in 2013, so far, natural gas generation is falling, while wind generation has continued to grow,” he said.