Just as climate talks kicked off in Paris last week, billionaire tech mogul Peter Thiel lobbed a nuclear challenge at his fellow billionaires, as well as politicians in Washington.

If we truly want a carbon-free future (and with it a chance at lowering, or at the least halting, the planet's rising heat levels), we need to cast our minds back to the 1960s, to our lost embrace of nuclear power.

In a hot-button editorial in The New York Times, the PayPal co-founder noted that wind and solar, while great alternatives to fossil fuels, "provide less than 2 percent of the world's energy" today. And they "aren't growing anywhere near fast enough," he writes, to replace the greenhouse-gas emitting stuff we haul from the ground.

That stuff pumps five billion metric tons of carbon dioxide into the air annually. And that's just in the U.S. Look no further than Beijing's smog-blanketed streets for visible proof of what the end times might look like.