The Department of Energy building in Washington. (Manuel Balce Ceneta/AP)

President Trump has appointed Daniel Simmons, a conservative scholar who sharply questioned the value of promoting renewable energy sources and curbs on greenhouse gas emissions, to oversee the Energy Department’s Office of Energy Efficiency and Renewable Energy (EERE), according to an email distributed to department employees.

The selection marks one of several recent Trump appointments to top energy and environmental posts, which appear to repudiate the Obama administration’s policies aimed at shifting the nation to low-carbon sources of electricity. Last week, Trump nominated David Bernhardt, a lobbyist who served at the Interior Department under George W. Bush, as Interior’s deputy secretary. And Alex Herrgott, who had served as majority deputy staff director at the Senate Environment and Public Works Committee, has joined the White House Council on Environmental Quality to serve as associate director for infrastructure.

Though no official announcement has been made, the acting head of the office, Steve Chalk, sent an email to DOE employees Monday saying that Simmons, a member of the Trump transition team, will become the principal deputy assistant secretary for EERE. Simmons will serve as acting assistant secretary until someone is confirmed by the Senate for the post, Chalk added. “Daniel has been with us through the transition and we look forward to his continued leadership and insights moving forward,” Chalk wrote.

Simmons’s appointment was first reported by E&E News.

EERE’s primary mission is to foster the development of renewable and energy-efficient technologies. That includes investments in electric vehicles; solar, geothermal and wind energy; and technologies to reduce energy use in U.S. buildings.

Before Trump was elected, Simmons served as vice president for policy at the Institute for Energy Research, a conservative think tank that espouses fossil fuel use and opposes the international climate agreement that nearly 200 countries struck in Paris in late 2015. The institute’s president, Thomas J. Pyle, headed the transition team for the Energy Department but has returned to his post in the private sector.

“I applaud President Trump and Secretary Perry for selecting Daniel for a leadership role at the Department of Energy,” Pyle said of Simmons’ appointment. “His years of experience in energy and environmental policy and appreciation for the power of free markets and consumer choice will bring a fresh perspective to the agency.”

Testifying before Congress in July, Simmons criticized federal financial support for the Ivanpah power plant, an industrial-scale solar plant in California’s Mojave Desert.

“It is unseemly that the American taxpayer has contributed billions of dollars to these facilities,” Simmons said of the project, which is sponsored by Google and other private companies.

In a 2013 podcast with the Heartland Institute, a libertarian public policy think tank, Simmons argued that pursuing renewable energy could harm people’s pocketbooks.

“The most simple of all points is that no matter what the renewable guys say, what they will admit is that their type of power — the wind and solar — is more expensive and will increase the price of electricity,” he said. “And in an economy that is struggling, it is critical that we do everything we can to keep prices low.”

At a Politico energy forum last year, he was direct about his disdain for federal subsidies for renewable energy.

“I think that everything should be treated equally across the board,” Simmons said. “We have to look at the track record of the oil and gas industry [which is] producing low-cost, reliable energy, particularly when the alternative is much, much higher prices.

Simmons’s appointment is likely to spark criticism from the same environmentalists who were quick to decry Bernhardt’s nomination. In his capacity as a partner at Brownstein, Hyatt, Farber and Schreck, Bernhardt represented oil and gas firms, mining companies and agricultural interests.

“Appointing a lobbyist like Bernhardt shows just how empty Donald Trump’s promise to drain the swamp was,” said Brett Hartl, government affairs director at the Center for Biological Diversity, an advocacy group. “From Scott Pruitt to Bernhardt, President Trump has assembled the most anti-environmental administration in history.”

Herrgott’s appointment, by contrast, is likely to be less controversial. While Herrgott worked for Sen. James M. Inhofe (R-Okla.), who has been a leading skeptic of climate science and an opponent of Obama administration plans to cut carbon emissions, he also worked with union officials and Democrats on the Hill to help ensure passage of key infrastructure measures, such as the 2015 Fixing America’s Surface Transportation (FAST) Act and the 2016 reauthorization of the Water Resources Development Act.

Americans for Transportation Mobility executive director Ed Mortimer, whose U.S. Chamber of Commerce-led group is made up of both business and labor interests, praised Herrgott’s selection.

“The ATM coalition is glad to see someone like Alex, who has experience with and an understanding of transportation issues, join the administration as it gears up to formulate a plan to modernize America’s infrastructure.” Mortimer said in a statement.

Staff writer Chris Mooney contributed to this report.