The following video is part of our "Motley Fool Conversations" series, in which consumer goods editor and analyst Austin Smith discusses topics across the investing world.

In today's edition, Austin weighs the case for two long-shot natural gas stocks, Westport and Clean Energy Fuels. While there is a lot to like about both companies, he is going to give the nod to Clean Energy Fuels because of what he sees as an inherent economic moat, not to mention that it is cheaper on many of the same metrics. Westport's case for the long term is sensitive to key patents, which eventually expire or can be engineered around. Clean Energy Fuels, on the other hand, is building out an infrastructure that's much harder to replicate.

As great as these energy stocks are, they serve a niche energy segment. If you're looking for a more complete energy holding I suggest "The Only Energy Stock You'll Ever Need." It's a well-positioned equipment provider that's poised to make investors today rich off the next energy spike. Read more about it.