Congress is heading home for its August recess having passed the first significant energy legislation, aside from some tax changes, since 2009, after the Senate approved two bills on Thursday that clear the way for faster licensing of hydroelectric projects.

“I wouldn’t call it major,” a Senate aide acknowledged. But apart from the stimulus in 2009 and various tax credits, including one for wind energy last December, Congress has not reached agreement on any energy legislation in four years.

The Senate unanimously approved two bills that had been passed by the House in February. They are hardly radical; they streamline the procedure for licensing small hydroelectric projects.

Senator Lisa Murkowski, Republican of Alaska and the ranking minority member of the Senate Energy Committee, pointed out that only 3 percent of the 80,000 dams in the United States are set up to generate electricity. “Hydropower is our greatest untapped potential for generating cost-effective, carbon-free energy,” she said in a statement.

Senator Ron Wyden, Democrat of Oregon, the chairman of the committee, added, “Capitalizing on the power potential of existing dams, pipes and conduits is the kind of practical thinking our country needs to generate more renewable energy and cut our carbon footprint.”

Some questions that are far more contentious remain on the legislative docket. Mr. Wyden and Ms. Murkowski are two of the main sponsors of a bill to restart the search for a nuclear waste burial site. It is sure to face tough sledding, partly because Republicans in the House are still hoping to revive the Yucca Mountain project near Las Vegas, which was killed by President Obama, partly at the urging of Senator Harry Reid of Nevada, the Democratic leader.

And a bill promoting energy efficiency, sponsored by Senators Jeanne Shaheen, Democrat of New Hampshire, and Rob Portman, Republican of Ohio, was approved by a Senate committee but has not been taken up by the full Senate.

Other issues have not even made it that far, including legislation regarding a carbon tax to address climate change and a restructuring of the electric grid, which is not set up to meet modern environmental goals.