Republican presidential candidate John McCain chose Alaska Gov. Sarah Palin as his running mate Friday, touting her as a champion for "new energy sources."

The short announcement posted on McCain's Website described Palin as someone who has "challenged the influence of the big oil companies while fighting for the development of new energy resources. She leads a state that matters to every one of us – Alaska has significant energy resources and she has been a leader in the fight to make America energy independent."

However, her definition of "new energy resources" is unclear. Palin, who was elected in 2006, is a staunch supporter of oil and gas drilling. She favors the opening of the Arctic National Wildlife Refuge for oil drilling, and she has carved out a reputation as a political reformer who isn't afraid to clash with senior members of her own party.

The Sierra Club was quick to point out a story published by the Post and Courier in Charles, S.C., in August that underscored Palin's weak stance on renewable energy. "Alternative energy solutions are far from imminent and would require more than 10 years to develop," Palin said. 

Palin has supported renewable energy in the past. In May, she signed a bill to spend $250 million over the next five years on renewable energy power plants from sources that includesolar wind, hydroelectric and natural gas.

This month, Palin signed a bill awarding TransCanada Pipelines the license to build a pipeline that costs an estimated $30 billion to transport natural gas from a new natural gas treatment plan in Prudhoe Bay on the North Slope to other states. The state would reimburse up $500 million of the project's cost.

Palin has praised Democratic presidential candidate Sen. Barack Obama for advocating more oil and gas production in Alaska in his energy plan. The same plan has received some praise from T. Boone Pickens, an oilman who has become a big natural wind and energy champion.

Pickens has become a celebrity of the national energy policy debate by launching an aggressive media campaign to promote his views (see T. Boone Pickens has a Plan and Summit Aims for Energy Policy Compromises).

Before becoming the governor, Palin was a councilwoman and then mayor of Wasilla, near Anchorage. She ran for lieutenant governor in 2002 but was unsuccessful.

She served on the Alaska Oil and Gas Commission, but resigned after a year to protest what she said were ethical violations by fellow commissioner Republican state chairman, Randy Ruedrich. Ruedrich later agreed to pay a $12,000 fine for breaking state ethics laws by conducting Republican party business in his office and providing confidential legal documents to a lobbyist. 

But Palin also has been under scrutiny for a potential ethics violation. The Republican-controlled Legislature has launched an investigation into an allegation that she fired the state's public safety commissioner because he refused to dismiss her former brother-in-law, a state trooper who went through a contentious divorce with her sister.

Will picking Palin draw a sharper divide between McCain and the Democratic presidential candidate Barack Obama?

Both presidential candidates have said they would support funding for renewable energy, biofuels, electric cars and a program to cap carbon-dioxide emissions and allow companies to trade emissions allowances.

Federal, state and local Republican and Democratic lawmakers, along with scientists and entrepreneurs, met in Las Vegas earlier this month to discuss energy policies. The goal was to produce an agenda that both parties would support, since many attempts by Congress to pass a new energy bill have failed this year (see Summit Produces Clean-Energy Agenda).

Palin has far less political experience than Sen. Joseph Biden, D-Del., Obama's running mate. After three decades in the Senate, Biden has built a reputation for his strong support of renewable energy and other green technologies (see Earth2Tech's post providing a closer look at Biden's stance on energy and climate change).