When es to energy policy, there is no perfect fuel. But in these debates, as elsewhere, the imaginary perfect fuel cannot e the enemy of the good.

And for the first time in recent memory, this means that nuclear energy, by all accounts a good alternative for the scale of demand we face, might be getting a seat at the table. Coal, which still provides more than half of the energy for the American grid, is cheap and plentiful, but environmentally and politically costly. And according to Popular Mechanics, it can only be “cleaned” up so much. That leaves a huge gap for other sources to fill.

As James B. Meigs writes,

Coal will never be clean. It is possible to make coal emissions cleaner. In fact, e a long way since the ’70s in finding ways to reduce sulfur–dioxide and nitrogen-oxide emissions, and more progress can be made. But the nut of the clean-coal sales pitch is that we can also bottle up the CO2 produced when coal is burned, most likely by burying it deep in the earth. That may be possible in theory, but it’s devilishly difficult in practice.

The rest of the piece goes on to argue how we’re really talking about “cleaner” coal, rather than “clean” coal. Remember that debate over whether it was appropriate to call sex with various forms of birth control “safe” or “safer”? We might well see a similar shift in language about coal from “clean” to “cleaner.”

But what about so-called “alternative” energy sources, like geothermal, wind, and solar? Well, as John Whitehead over at the Environmental Economics blog concludes, “…potential supplies of wind and solar don’t appear to be large enough pletely replace oil and coal in the foreseeable future. If that is the purpose, then no, alternative energy can not effectively replace fossil fuels.”

So for the foreseeable future what we’re looking at in terms of the sources of our energy, in the face of growing global demand, is a mélange; coal, oil, natural gas, and yes, wind and solar, all have their place. But so does nuclear, and that’s one of the positive takeaways from President Obama’s State of the Union address, in which mended “building a new generation of safe, clean nuclear power plants in this country.”

The challenging for existing energy firms will be to adjust to providing the right sources in this mixture. One way to do this is to be cognizant of the alternatives and their relative costs and benefits. ExxonMobil’s “Energy Outlook” released at the end of last year predicted that the growth of some of the newer sources, like wind and solar, would grow faster than some of the conventional sources, like oil and coal.

This means that a focus on innovation and efficiency will move some surprising players to fill the demand for cleaner energy, and the vision of increasingly transient reliance on fossil fuels might e to pass.

As I wrote in 2006, “The human stewardship of oil and other petroleum-based fuels entails a responsibility to use the economic opportunities they afford to find and integrate other renewable, sustainable, and cleaner sources of energy, especially represented by the promise of nuclear power, into our long-term supply.”