If there's one thing we have plenty of in this world, it's poop. Not to be gross, but think about it. From the time humans are born we start creating feces and we don't stop until we die. At the moment, all of that poo is a menace. We have to find ways to collect it and dispose of it so that it doesn't create problems by spreading infection and disrupting water supplies. But what if we could find a way to make poop useful? Or even valuable?

That was the question posed recently by a U.N. think tank. What if we could turn human waste from a sanitation issue into an energy resource?

According to experts, once you get rid of all of the water, human feces is essentially 25 to 45 percent gaseous methane. When dried and concentrated, that methane has an energy content similar to coal. But instead of creating the environmental issues that result from coal mining, the use of human waste as an energy source would rid the world of an environmental pollutant.

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In a new report, the think tank outlined this theory and estimated that, collectively, the value of the world's human poop would be around $9.5 billion. That's a pretty penny for a pile of poop. And that's just the number twos! Human urine also contains nutrients in the form of phosphorous, potassium, sulphur and nitrogen. With a little recycling, this plentiful resource could be converted to crop fertilizers that would reduce the need for added chemicals.

Of course, the U.N. think tank hasn't figured out exactly how all of this will work. Turning human poo into an energy resource on a global level would involve a huge infrastructure of collection and conversion. And it's probably a good idea to figure out ahead of time what environmental consequences would occur if we started burning tons of human waste around the world.

But two pilot programs are already underway in Uganda and Kenya — countries in which sanitation is a huge issue. And depending upon how these programs work, the big-picture thinkers may come up with a plan to turn waste into wealth on a global scale.

One thing's for sure: This is one renewable resource that we won't run out of anytime soon.