When the U.S. energy world is on fire the way it is, it's easy for investors to get caught up in production numbers and pipeline volumes and forget all about boring numbers like cost of capital. But given that we may start to see interest rates tick up in the next year, it's time to revisit the important role that cost of capital plays in our midstream investments.

In this video, Fool.com contributor Aimee Duffy takes a look at what cost of capital is, and how it can vary from MLP to MLP.

Fool contributor Aimee Duffy has no position in any stocks mentioned. The Motley Fool recommends Enterprise Products Partners L.P. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.