What, exactly, is clean energy?

Easy to say. Who is going to stand up and say, "No, we want dirty energy!"

But so far, agreement on the definition of "clean energy" has been elusive.

As the president said next, "Some folks want wind and solar. Others want nuclear, clean coal and natural gas. To meet this goal, we will need them all - and I urge Democrats and Republicans to work together to make it happen."

The coal industry certainly touts clean coal. Critics say that with current technology, there is no such thing. It's an oxymoron.

As for natural gas, will the dirty extraction that some say exists make up for the cleaner-burning flame?

And until the nation comes up with a way to deal with spent fuel rods - not to mention a way to fund these behemoth projects - is nuclear power really a satisfactory answer?

Thorny questions, all.

Here's a smattering of reaction to this new goal.

- Eileen Claussen, president, Pew Center on Global Climate Change: "President Obama understands that capitalizing on today's clean energy opportunities will propel American job growth and help ensure that the United States has the most competitive and innovative economy in the world. Providing the regulatory certainty businesses need for industries to invest in clean energy to drive economic growth should be a key Administration priority over the next two years."

- Scott Segal, an energy expert at Bracewell and Giuliani, a firm that often represents industry: The President's challenge is interesting because he mentions a wide range of clean technologies, including coal, that could meet his clean energy standard. That is a positive development and underscores the notion that traditional fuels, including coal, can be utilized in an environmentally-friendly way. But the devil is in the details; what will qualify and in what proportions. A poorly calibrated clean energy standard can be as harmful to the economy as a restrictive renewable portfolio standard. As a general proposition, governmental mandates can have unintended consequences. For example, the cost impact of the President's proposal must be viewed in the context of the substantial regulatory burdens his Administration is also imposing on the power sector. These regulations, which include Clean Air standards, waste regulations and water regulations, collectively place approximately half of US electric generation at risk. Coal-fired capacity, for example, indirectly or directly represents over a trillion dollars in gross economic output and almost seven million jobs. Adding an ill-fitting clean energy standard to a substantial regulatory burden could be a great risk."

- Frances Beinecke, president of the Natural Resources Defense Council: "The president got it right. Nothing's more urgent than creating American jobs and protecting our health. The best way to do that is to invest in a clean energy future that makes our workers more competitive, our companies stronger, our country more secure and all of us healthier."

- Alex Flint, the Nuclear Energy Institute's senior vice president of governmental affairs: "It was encouraging to hear the President lead with a call for an inclusive clean energy policy. Nuclear energy provides 70 percent of the nation's carbon-free electricity supply and, especially if we are to develop 1 million electric cars by 2015 as he proposed, we're going to need to develop every possible form of low-carbon technology. The President's continued commitment to nuclear energy has reinforced the bipartisan nature of support for nuclear energy. This properly highlights as a policy issue the strategic importance of the United States maintaining a leading role as a developer of advanced nuclear energy technologies, for use domestically and for export to a fast-growing global market. The President, House Speaker Boehner and members of Congress on both sides of the aisle have identified nuclear energy as an area of potential cooperation; it is a linchpin to the success of meeting the significant energy challenges that our nation faces."

- A joint statement from the Center for American Progress Action Fund, Environment America, League of Conservation Voters, Natural Resources Defense Council, Sierra Club and Union of Concerned Scientists: "We are ... pleased that the President recognized that we cannot rely on 19th Century energy technology to power our 21st Century economy. In establishing a clean energy goal, getting the details right is crucial: we need a goal that will promote truly clean energy innovations, not become a Christmas tree for nuclear subsidies, interference with critical pollution standards, and environmentally destructive fossil fuel development. ... Any energy proposal that blocks, weakens, or delays vital clean air standards to reduce harmful carbon pollution is a non-starter because it will stifle innovation and eliminate clean energy jobs. "

(c) 2011, The Philadelphia Inquirer.
Distributed by McClatchy-Tribune Information Services.