Let’s imagine for a moment that Al Gore’s wish is granted and we all gave up our fossil-fuel guzzling, carbon-dioxide spewing cars in favor of efficient, gas-electric hybrids, like the Toyota Prius. While endangered penguins celebrate the re-growth of the polar ice caps, and we all enjoy watching the executives at Exxon Mobil trade in their Italian suits for blue Wal-Mart greeter vests, maybe we should also be casting an uneasy eye on China. Assuming Al Gore’s wish-granting genie also provided a Prius to everyone in China, why should we be concerned? Because China is the world’s largest producer of rare earth metals, used in everything from wind turbine generators to electric Prius motors, and as demand for these metals has ramped up, China has begun to limit exports.

For those of you who are not peering at your favorite periodic table of elements poster, the rare earth metals include 15 entries on the table, such as neodymium, terbium, dysprosium and lanthanum, used in various ways to make hybrid car batteries. The Automotive News reports that, according to Jack Lifton, an independent commodities consultant and strategic metals expert, the Prius is "the biggest user of rare earths of any object in the world." This rare earths guzzler, the Prius, is certainly the most popular gas-electric hybrid vehicle in the U.S., capturing 70% of market share. Combining the demand for the Prius, plus other hybrids, and wind turbines to generate cleaner electricity, there is expected to be a shortage of these rare earth metals soon, within the next few years. China has long been a shrewd business entity, and will certainly leverage its natural resources much the same way OPEC has done, which could put the Prius in the same pinch the Chevrolet Volt would be in if they can't find another source of lithium — but that’s another story.

So what’s Toyota to do? Always planning ahead, they’re eying new sources of these metals, possibly in Canada or Vietnam. For hybrid automakers here in the U.S., a rare earths mine in California is slated to re-open in 2012. In the meantime, as Toyota gears up to sell more than half a million of their Prius here in the U.S. in the next two years, maybe Al Gore’s genie can work on finding new sources of rare earth metals too, because the last thing we need on our road to energy independence is another supply roadblock.