President Barack Obama said the government will authorize the leasing of federal waters for renewable energy projects, part of the administration's sweeping agenda to spark a new clean energy industry and ease the country's reliance on oil.

"On this Earth Day, it is time for us to lay a new foundation for economic growth by beginning a new era of energy exploration in America," Obama said Wednesday, according to remarks prepared for delivery.

Obama traveled to Newton, Iowa, to mark Earth Day and tour a former Maytag plant that is now used to produce towers for wind energy production. The White House says the town is an example of how clean energy investments can create jobs and help recession-battered areas remake themselves. Trinity Structural Towers employs dozens of former Maytag workers in Newton, according to the administration.

Obama's remarks there provided a tour of the White House's energy agenda, from its plans for a cap-and-trade program to tax credits for fuel-efficient cars. He also unveiled the offshore program, in which federal waters would be used to generate electricity from wind and ocean currents.

Obama said the initiative will pave the way for major new investments in clean energy. "There is enormous interest in wind projects off the coasts of New Jersey and Delaware, and today's announcement will enable these projects to move forward," he said, adding that a full use of wind energy can produce up to 20% of the country's electricity needs by 2030 and create as many as 250,000 jobs.

"As with so many clean energy investments, it's win-win: good for environment and great for our economy," Obama said.

As the president traveled to Iowa Wednesday, a trio of top administration officials pressed lawmakers to move forward with legislation capping greenhouse gas emissions. Their testimony at a Congressional hearing follows last week's finding by the Environmental Protection Agency that greenhouse gases endanger public health and welfare, and faces fierce opposition from Republicans worried about the cost of the plan.

"There is no question that we have to regulate carbon pollution; the only question is how we do so," Obama said. "I believe the best approach is through legislation that places a market-based cap on these kinds of emissions."

House Republican Leader John Boehner, R-Ohio, called the proposal a "national energy tax that will destroy countless jobs and raise energy prices on families and small businesses already struggling during this recession."

In Newton, Obama linked administration-backed energy plans with long-term economic prosperity and job creation, arguments the White House uses to counter GOP complaints about cost.

"The choice we face is not between saving our environment and saving our economy - it's a choice between prosperity and decline," Obama said.

"We can remain the world's leading importer of oil, or we can become the world's leading exporter of clean energy. We can allow climate change to wreak unnatural havoc, or we can create jobs working to prevent its worst effects. We can hand over the jobs of the 21st century to our competitors - or we can confront what countries in Europe and Asia have already recognized as both a challenge and an opportunity: The nation that leads the world in creating new sources of clean energy will be the nation that leads the 21st century global economy."

While Obama called for more renewable energy, he also said domestic production of oil and natural gas should be increased, and called for the safe use of nuclear power.

He also said General Motors Corp. (GM) and Chrysler LLC, struggling to create viability plans under a government deadline, face "difficult challenges" and need to build "the cars of the future."

"We must create the incentives for companies to develop the next generation of clean energy vehicles - and for Americans to drive them," Obama said.

-By Henry J. Pulizzi, Dow Jones Newswires; 202-862-9256; henry.pulizzi@dowjones.com