A few weeks ago a ship carrying an ultralight oil known as condensate left the U.S. on its way to South Korea. While the oil was minimally refined and technically qualified as a refined petroleum product, it has been regarded by many as the first step to lifting America's four-decade-old ban on oil exports. But what is pretty surprising is that at the same time producers are seeking to export oil as well as additional volumes of natural gas and coal, America continues to import these same commodities from other countries. Lets take a close look why that's happening and why it's not likely to stop anytime soon. 

Why America still imports oil
Thanks to the combination of horizontal drilling and hydraulic fracturing, America has unlocked billions of barrels of oil trapped within tight shale formations. The surging production from shale, along with falling consumption, has led to a dramatic reduction in net oil imports, as the following chart notes.

Source: EIA 

But despite the surge in oil supply America still imports a lot of it. In 2013, 33% of the oil consumed in the U.S. was imported, which is the lowest level since 1985 and down from 40% the year before. That being said, even as oil imports drop, half of the oil consumed in American refineries is oil that has been imported. 

The reason American refineries prefer imported oil is because that's the oil these refineries have been equipped to handle. A bulk of the oil that's imported actually comes from the Canadian oil sands, which accounted for roughly a third of our net oil imports and Venezuela, which supplies more than 10% of our net imports. Both of these countries produce what's known as heavy oil. Meanwhile, the oil that comes out of shale plays in Texas and North Dakota is light oil. It's a type of oil that refineries weren't expecting to be refining as the energy industry never saw the the shale oil boom coming and instead invested to build the capacity to refine the heavy oil coming from Canada and Venezuela. Now, American refineries are overwhelmed with light oil, which is why producers are pushing for an end to the export ban even as the country continues to import the oil from other nations.

Why America still imports natural gas
A few short years ago America was thought to have just a dozen years of natural gas reserves left. But thanks to the shale boom the country now sits on reserves big enough to last the country nearly a century. Because we have so much natural gas, next year America will export its first cargos of liquefied natural gas from a facility that originally was intended to import natural gas. The shale gas boom rendered import facilities like it useless, which is why nearly all of them are being converted to export natural gas. Yet, despite the fact that natural gas production has surged to the point that America has more than it can use, the country still imports natural gas as the following chart notes. 

Source: EIA 

While net natural gas imports have fallen to the lowest level since 1989, they have yet to vanish completely. One of the reasons for this is because there still isn't enough pipeline capacity from places like the Marcellus shale to deliver enough natural gas to meet the needs of places like New England in the winter. This is why most of the country's remaining natural gas imports, a whopping 97% in this case, come from Canada. 

Last winter, for example, natural gas from a Canadian offshore project from Encana (OVV -0.43%) helped keep Boston warm. Unfortunately, that came at an ultra-high cost as the price for natural gas in Boston was more than seven times higher than the price of natural gas in Pennsylvania. While that state was oversupplied due to the abundance of gas from the Marcellus Shale there isn't enough pipeline capacity to get it to Boston. So, until that capacity is built America will likely keep importing gas from Canada. 

Why America still imports coal
While it's no surprise that America still imports oil and it's probably even understandable why there's still some residual natural gas imports, what is likely surprising to learn is that America actually imports coal. In fact, through the first six months of this year coal imports surged 44% to 5.4 metric tons. While that's less than 1% of the expected 862 million tons of coal expected to be consumed in America this year, it's still a surprise that we import coal at all. 

Two thirds of the coal imported in America is coming from Colombia. The reason for this is that it costs just $15 per ton to get Colombian coal shipped into power plants in Florida. Meanwhile, it would cost $26 per ton to get coal from mines in Central Appalachia to those plants. There are three reasons why Colombian coal is cheaper. First, labor costs are cheaper. Second, coal can be moved on ships carrying 50,000 tons of coal as opposed to trains that carry 100 rail cars holding 100 tons of coal apiece. And finally, as the following chart notes, coal production in the country has fallen dramatically over the past few years as miners cut capacity in order to improve pricing.

Source: EIA 

So, despite having the largest coal reserves in the world, which are enough to last the country 290 years, America still imports coal simply because it's cheaper to do so.

Final thoughts
Despite our vast energy resources America still imports a lot of energy. We import specific types of oil because that's what our refineries can handle. We import natural gas because we don't yet have enough pipelines in place to meet peak demand. And we even import coal because in some instances it can be cheaper to do so. That's what happens when we live in a market-driven economy, so no matter how much energy we produce America will continue to import it when it's cheaper and more efficient to do so.