Energy issues dominated 2013 from the start with President Obama placing climate change at the center of his second inaugural speech in January. That speech set the tone for Obama's second-term legacy, placing climate regulations as the cornerstone surrounded by the ongoing battle to make energy clean and U.S. energy independent.

1. The climate agenda

After hitting on climate change mitigation efforts in his second inaugural address, President Obama unveiled his national plan on climate at Georgetown University in June. The plan centered on reducing carbon pollution. This year the administration and Environmental Protection Agency have utilized powers afforded under the Clean Air Act to craft executive orders and regulations to limit carbon emissions from existing and new power plants. Gina McCarthy released the central component of Obama's climate legacy in September -- draft rules to cut greenhouse gas emissions from new power plants.

Republicans were quick to blast the administration for its climate initiatives. Obama's efforts quickly became known as the "war on coal" among the GOP. And the debate isn't over. Sen. Mitch McConnell (R-Ky.) has vowed to make Obama's "attacks" on coal a key issue in his 2014 reelection campaign.

In case you want to get up to speed, here are some of the stories on Obama's climate agenda that ran on E2-Wire in 2013…

EPA releases draft rules to cut emissions from power plants

Filibuster change clears path for Obama climate regulations

Obama to lay out national plan on climate change Tuesday

Obama grasps for climate legacy as second-term agenda crumbles

Obama change featured prominently in Obama's second inaugural address

2. Keystone XL

Since TransCanada first proposed the Keystone XL pipeline five years ago, it has been a topic of much heated debate, but in 2013 that debate reached new extremes. Following the release of the State Department's draft environmental review in March -- which found the pipeline would not speed up expansion of the oil sands or have a significant impact on the environment -- the oil industry and green groups ramped up outreach on the pipeline in an effort to convince Obama of ruling one way or the other. The EPA issued a scathing review of State's report in April, saying it included "insufficient information" on environmental issues. And to make matters worse, State's internal watchdog launched an inquiry in August into whether the contractor that worked on the environmental review, Environmental Resources Management, failed to disclose its ties to Keystone XL developer TransCanada. Now, both sides are playing the waiting game. TransCanada CEO remains "very confident" that Obama will approve the pipeline but green groups and billionaire activist Tom Steyer -- a new face in the campaign to halt Keystone XL -- will continue the fight against the pipeline. State is expected to release its final environmental impact statement any day now. Obama could announce his decision on the pipeline as early as March.

Here are some stories on Keystone XL that ran on E2-Wire in 2013...

Oil shipments to begin in Keystone XL's southern leg

Keystone developer: We 'won't quit'

State Dept. watchdog launches inquiry into Keystone environmental review

EPA balks at State's 'insufficient' review of Keystone's XL route

3. Crude oil production outpacing imports

The Energy Department's Information Administration announced in November that U.S. exports surpassed foreign imports for the first time in roughly 20 years. The Obama administration proceeded to take credit for the surge in crude production. The U.S. churned out more crude oil in October than it imported, the first time since 1995. Press Secretary Jay Carney led off his daily briefing with the news the same day of the announcement, crediting President Obama's fuel economy and carbon pollution policies for the increase. In an attempt to weather the storm over ObamaCare, the administration seized on the crude oil milestone, driving the conversation toward production. After the briefing in early November, the administration continued to tout the news through social media outlets and last week President Obama led his final press briefing with the crude oil milestone.

Here on some stories on the crude oil milestone that ran on E2-Wire in 2013…

Administration takes credit for crude oil milestone

Embattled administration touts oil milestone
4. The natural gas revolution

The U.S. may be the Saudi Arabia of natural gas as production reached highs in 2013 and is expected to only increase. Natural gas producers expect the industry to continue booming and possibly offer a cure to China's air pollution woes. Congress held inquiries into the shale gas boom as its greenhouse gas footprint and overall environmental impact are still in question. While natural gas production helps drive down U.S. carbon emissions with power companies switching from coal, it still emits the potent greenhouse gas methane. 

Here are some of the stories about the natural gas boom that ran on E2-Wire in 2013...

EPA chief visiting China amid record air pollution

Senate panel weighs shale gas boom's climate impact

Energy Secretary: Natural gas helps battle climate change -- for now



5. Retreat on Ethanol

The debate over the country's renewable fuel mandate, which determines how much ethanol and biofuels refiners must blend into the nation's fuel supply, raged in 2013. All the way up to the EPA's release of its draft proposal, the oil industry and biofuel companies duked it out in an effort to sway the administration. The EPA shocked biofuel companies with the proposal released in November, which scaled back the amount of ethanol and other biofuels that must be blended, citing the blend wall as its reason behind the retreat. The blend wall is the highest amount of ethanol that the market can currently accommodate, but biofuel producers call it false logic touted by the oil industry. The EPA is currently taking comments on its proposed draft, which will be finalized sometime next year.

Here are some of the stories about the renewable fuel mandate that ran on E2-Wire in 2013…

EPA retreats on ethanol mandate

EPA fuel mandate imperils biofuel industry, producers warn

EPA: Ethanol limit has been reached

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