President Barack Obama is expected to nominate soon a new Secretary of Energy and a new administrator for the Environmental Protection Agency. The conventional wisdom is that Ernest Moniz will be tapped to head the Department of Energy and Gina McCarthy will be nominated to head the EPA.

Moniz is a professor at the Massachusetts Institute of Technology and Director of the MIT Energy Initiative, an energy-focused think tank. McCarthy works for EPA as the Assistant Administrator for Air and Radiation.

Neither Moniz nor McCarthy would signal a radical departure for U.S. energy policy. On the big issues, such as U.S. climate policy, their priorities have already been set by the president.

In his second inaugural address and most recent State of the Union address, Obama indicated that addressing climate change will be his administration’s top energy-related priority during his second term. Since the Republican-controlled House of Representatives is unlikely to pass new climate legislation during the next two years, government agencies will be tasked with creating policies that will help to meet the president’s goals.

EPA is expected play the leading role in shaping U.S. climate and energy policy. DOE manages much of the government’s basic energy-related R&D funding, which means the agency could be influential in determining which new energy technologies eventually come to market. EPA policies are more relevant for existing energy producers.

During 2013, EPA is expected to focus on new greenhouse gas regulations for power plants. A recent Bloomberg Government study concluded (subscription required) that although new EPA regulations will help to reduce GHG emissions, they’re unlikely to achieve the 80 percent reduction recommended by most climate scientists. To meet the long-term climate targets, Congress would need to pass legislation.

Whether McCarthy gets the nomination or somebody else does, EPA’s upcoming climate-focused regulations will probably be fiercely debated during confirmation hearings. Congress never explicitly passed any laws instructing EPA to regulate greenhouse gas emissions, and the agency’s plans are likely to draw criticism from Republicans.

Compared with EPA, the confirmation hearings for Secretary of Energy are likely to be less contentious. The DOE is expected to approve or reject facility licenses to export liquefied natural gas during 2013. This will probably among the high profile issues discussed during the DOE confirmation hearings. If Moniz gets the nomination, he probably will express support for increased LNG exports.