The Logistics of Natural Gas

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0:00An American household is typically delivered two physical goods as utilities. The first

0:06is water—and the ability to turn on a tap and reliably have fresh, clean water year round,

0:11no matter recent precipitation is undoubtedly impressive, but a water utility is typically

0:16a fairly local service. Except in a few, fascinating exceptions, water tends to be

0:21gathered from a natural source, processed, and delivered to households fairly nearby.

0:26It’s a fairly intuitive, fairly straightforward process that has been going on, in some form,

0:31for hundreds, even thousands of years. Natural gas, though—that’s a modern marvel.

0:38The general rule, across the world, is that natural gas production happens where people

0:42are not. This is in part a happenstance of geography, in part the consequence of an

0:47aversion to proximity to production, but what it means is that gas often has to travel hundreds,

0:52if not thousands of miles to get to its end-user. To get low-density, flammable gas across an entire

0:59continent is far from easy, and it’s even harder to do so profitably. Whereas gasoline and other

1:05liquid fuels are dense enough that the cost of transport to the end-user by truck is marginal

1:10relative to the overall cost, the same is not true for natural gas. Therefore, through time,

1:16what has turned the previously worthless gas into a profitable commodity was figuring out how to

1:21make the transport economics work. And the answer for that was pipelines—really, really long ones.

1:29Taking the example of an end-user in Basalt, Colorado, their town’s local

1:33network hooks up to a larger transmission pipeline that follows the area’s highway

1:37down the valley until around here—under this golf course, this dead-end offshoot

1:42connects with the long-distance transmission pipelines spanning across Colorado. Now,

1:47the fact that this happens under a golf course demonstrates something important—the pipeline

1:51operator does not own the land through which the pipeline passes. Rather, they own the right for

1:57the pipeline to pass through others’ land—they own an easement. When a pipeline is constructed,

2:02the company negotiates with landowners to purchase the easement or, if negotiations don’t go well,

2:07acquires it through eminent domain. In exchange, the landowner gets paid a lump sum, more of

2:13less equivalent to the reduction in property value caused by the new easement. After all,

2:18the property value will be lower. Not only will buyers be wary of living near a pipeline due to

2:23the low but non-zero risk of an accident, but easements also come with restrictions on what

2:28one can do with the land. Typically, you can’t build any buildings, you can’t plant any trees,

2:33you really can only have pavement, grass, or dirt. The operator needs to be able to access

2:38the pipeline for maintenance and repair at any time so they can’t have a permanent structure in

2:43the way. And these easements are legally-binding for eternity—they are baked in with a property’s

2:48title, so buyers must still abide by the restrictions agreed upon by the original seller.

2:53Here, the adjacent housing development is laid out in a way to avoid the largely-invisible

2:58right-of-way, then on the other side of the river the right-of-way slides between buildings,

3:02barely even visible from a satellite view. But as the hills start, the right-of-way takes its

3:07more typical form—a 50-foot wide stretch of land devoid of trees. And that lack of

3:12trees originates, of course, from construction. That process is fairly straightforward. First,

3:18heavy machinery is used to dig a trench. Then, sections of pipe are laid out next to the trench,

3:24and a pipe-bending machine comes through to bend the pipe to follow the topography. Next,

3:29these shorter sections are welded together into longer sections, and the welds are strictly

3:33inspected—after all, structural integrity is critically necessary to prevent an incident.

3:39Once complete, they’ll place these long sections in the trench on sandbags to prevent damage to

3:43their protective coating, then soft, rock-free dirt is placed to directly surround the pipe,

3:48followed by the previously-removed dirt to fill the rest of the trench. From there,

3:52the crews test the pipe by filling it with water and pressurizing it well beyond its normal

3:56operating pressure, and that’s about it. Pipeline construction is relatively straightforward and

4:02moves relatively fast—under the right conditions, crews can install upward of a mile of pipe a day,

4:08often across quite remote environments. But there is more to pipeline construction than

4:14just constructing the pipe—after all, if you put natural gas into a pipeline in Texas, it doesn’t

4:20just magically flow to Colorado. That’s why you need this—a compressor station. As the name

4:26implies, these are the facilities that compress the gas, and it’s this pressure that propels the

4:31gas forward through the pipeline at a speed of about 25 miles or 40 kilometers per hour. But

4:37they’re also important for making the economics work. An average household uses about 200 cubic

4:42feet of natural gas a day. That’s a lot of volume of gas—it’d fill up a 6-foot, or 2-meter cube,

4:50or the volume of about ten fridges. The economics of transporting this gas would never work if it

4:56were done at its natural density. That’s why they compress it—quite a lot, in fact, to between 500

5:01and 1400 pounds per square inch, allowing a pipeline to be used far more efficiently.

5:07These compressor stations are also often home to so-called “pig launchers,” which

5:11are more humane than they sound. That’s because these are what are referred to as pigs—devices

5:17placed into the pipeline to perform some function. Some pigs clean the pipeline,

5:22whereas others are smart pigs fitted with sensors to inspect it for any vulnerabilities. While less

5:27relevant in natural gas pipelines, operators will even use pigs to separate out two different

5:32products moving through a pipeline—they might send a batch of traditional vehicle fuel, then a pig,

5:37then a batch of jet fuel, for example. And wherever there’s a pig launcher there’s also a pig

5:42catcher that’s able to remove the device from the pipeline while still allowing product to flow.

5:47Now, this pipeline eventually emerges from the mountains into another golf course, this time

5:51just south of the town of Eagle. From there it connects to another pipeline—right continues east,

5:57but left eventually dead-ends just a few miles down the road. This is common, because

6:02while one major category of customers for these long-distance transmission pipelines is the local

6:07utilities that distribute gas to local users, the other big customers are large industrial

6:12facilities that use so much natural gas that they have a direct connection to the long-distance

6:18pipelines. In this case, it’s a plant that turns gypsum mined nearby into plaster drywall, and it's

6:23energy-intensive enough that the facility operates its own 6 megawatt natural gas power plant.

6:29The rest of the pipeline, though, more or less follows the path of route 6, then diverts south

6:33over a set of hills before reconnecting with the highway and ending up here—another compressor

6:38station. Although, this compressor station isn’t operated by Black Hills Energy like the pipeline

6:43up until this point—it’s operated by Xcel Energy. That’s because here, the pipeline’s ownership

6:49changes, which is also abundantly common. Pipelines in the US are highly regulated by

6:56the Federal Energy Regulatory Commission and, as part of that, interstate pipeline operators are

7:01required to provide non-discriminatory open-access to all qualified shippers. Effectively, they’re

7:07not even allowed to provide preference to their own product. FERC also regulates rates—Black Hills

7:13Energy, for example, is allowed to charge $36.87 to reserve a dekatherm of pipeline capacity during

7:19the winter, when demand is higher. That guarantees capacity, then they’ll charge another 10 cents

7:25per dekatherm for the actual transmission. Alternately, shippers can pay just 94 cents

7:30per dekatherm, with no capacity charge, for “interruptible transportation,” where product

7:34is shipped only if there is available capacity. The fact that this system is open access is

7:39ultimately how product can find its way through the nation’s web of pipelines all the way from

7:43where it’s produced. A shipper might pay a dozen different companies for their transmission service

7:48to get the gas from its origin. And in the case of an end-user in Colorado,

7:52it’s quite likely that the origin for its gas is here—Texas’ Permian Basin.

7:59There, the natural gas is extracted from the ground and processed into its commodity form.

8:03The area’s primary industry is the more lucrative oil production, but natural gas

8:08is often a byproduct of that. Still to this day, many rigs burn off natural gas if they lack the

8:13infrastructure to divert it for sale, but an increasing number do capture both. But whether

8:19extracted via combined or dedicated rigs, it is often difficult to fluctuate production quickly

8:24to match demand. And demand fluctuates wildly considering so much of the use of the gas is for

8:30heating. So that’s the role of these 400 different natural gas storage sites dotted across America.

8:36Some of these sites are just the very areas where gas was previously extracted from—depleted

8:41underground caverns. Once all of that original gas is gathered, the giant Swiss-cheese holes

8:46in the ground—sometimes spanning thousands of acres—sit empty and that makes them ideal for

8:51storage. They also already have existing wells, existing extraction and injection methods,

8:56and existing pipeline connections. Here, gas is reinjected into the impermeable natural caverns

9:01some 1,000 to 5,000 feet, or 300 to 1,500 meters below the ground, where the working

9:07gas—the natural gas that is commodified—occupies the upper part of the cavern and a cushion gas

9:12maintains a pressure buffer at the bottom. Because the depleted natural gas fields are established,

9:17proven, and widespread, their geology and infrastructure generally makes them the most

9:21inexpensive and easiest way to store natural gas. There is, however, another method that crept into

9:27more use about a decade ago as the country ramped up some storage capacity: Salt caverns,

9:32which can quickly turn over storage since they can accept a higher ratio of working

9:37gas to cushion gas. Leaching out and creating salt caverns is expensive, but because of their high

9:42withdrawal and injection rate—which can cycle up to 12 times per year—that cost can be justified.

9:48This short withdrawal cycle is ideal for pumping energy into power plants during peak periods,

9:52and because more natural salt caverns are found in the South and Gulf area, this is

9:57where they’re increasingly being put to use. The third type, similar to depleted oil fields

10:02in structure, are drained aquifers. These share the characteristics of being underground natural

10:06storage areas, but because they were previously stored water the surfaces can be permeable and

10:11the caverns less explored. It’s more expensive to transform aquifers into natural gas storage

10:16so it’s primarily done in areas, like the Midwest, where depleted oil fields are less

10:20common. Furthermore, aquifers require up to 80 percent cushion gas, meaning the amount

10:25of working gas they actually hold is far less than something like a salt cavern,

10:29making injection and withdrawal more difficult. But not all the gas extracted in Texas,

10:35or anywhere in the US for that matter, will even be used in the US. Increasingly, gas is not only

10:41transported across a continent, but across the world. And to get to such far-flung markets,

10:47it’s moved as a liquid, crossing oceans, gulfs, seas, and straits in one of these.

10:53This is a Q-Max class liquefied natural gas carrier. There are 14 of them worldwide, and their

10:58classification signals that they are the very largest vessel capable of docking at Qatar’s LNG

11:04terminals, making them the largest LNG carriers in the world. But in terms of sheer capacity, these

11:10are small in comparison to their conventional oil tanker contemporaries. A Q-Max can carry

11:15some 266,000 cubic meters of liquefied natural gas whereas the world’s largest TI-class supertankers

11:22can carry up to 450,000 cubic meters of oil. And yet these conventional oil tankers, with their

11:28superior storage, come at a fraction of the cost of a LNG carrier, as the last TI-class supertanker

11:34cost $82 million in 2003, while a Q-Max runs in the $200 to $300 million range. While smaller,

11:43more expensive to build, and more expensive to maintain given the requirement of keeping natural

11:47gas in a fluid state, experts believe there will soon be more LNG tankers plodding across

11:52the oceans than oil tankers. The reason as to why has to do with some geography and some physics.

11:59On a global scale, the demand for natural gas is in places far from the supply. In 2023, these

12:05three countries were the largest LNG importers in the world, with China narrowly outpacing Japan.

12:11For decades, these three countries have been at the top of the list, with Japan the world’s

12:15number one year in year out until 2021. And for two of these three countries, total consumption

12:22exactly matches or very nearly matches imports. Put simply: Japan has very limited natural gas,

12:29and South Korea has almost none. And while China does have a strong domestic supply,

12:34it cannot nearly keep pace with its own demand. The difficulty is, most of the big suppliers are

12:40far away and across oceans that make any sort of pipeline project infeasible. So geography

12:46has dictated if natural gas is to get from the US or Qatar or Russia or Norway or Australia,

12:52it’s likely going to be by ship. But it’s physics that makes natural

12:56gas cost competitive. For natural gas to enter a liquid state, it needs to be cooled to and

13:01kept at -260° Fahrenheit or -162° Celsius—which is what makes LNG ships so expensive to build

13:10and expensive to run. But it’s worth the trade off because once cooled into a liquid, natural

13:15gas shrinks to 1/600th of its previous volume. While natural gas has been lobbied as a cleaner,

13:21more efficient energy source by proponents, it’s really this incredible transformation

13:25from voluminous gas to energy dense liquid that makes this energy source so remarkable, and now,

13:31so important on a global scale. By keeping the gas at -260 Fahrenheit, the common adage goes,

13:37a beach ball’s worth of gas shrinks down to the size of a ping pong ball. But that example lacks

13:42scale. Phrased in another way, that a single ship’s worth of LNG becomes 600 ship’s worth

13:48of gas in its natural state, it becomes easier to understand why LNG has skyrocketed in trade

13:53volume decade after decade—even if it’s incredibly expensive and labor intensive

13:59to keep the stuff at such a cold temperature. Before liquid natural gas can be loaded onto

14:04an expensive boat, it needs to be cooled down at an expensive liquefaction facility. At each

14:09liquefaction facility there are what the industry calls trains—where the gas is treated to remove

14:14impurities, then progressively cooled to turn raw gas into clean gas then clean gas into liquid

14:19gas. At Sabine Pass in coastal Louisiana, the oldest operational liquefaction terminal in the

14:25US—as well as the largest—there are currently six separate functional trains. The first five cost,

14:31as estimated by Cheniere Energy which owns and operates the facility, between $17.5 and $18.5

14:37billion dollars to build, while the sixth added later cost of about $2.5 billion. After trains,

14:43the product is then stored, awaiting a ship. At Sabine Pass, LNG is stored in five separate

14:49tanks capable of holding an absurd 500 million cubic meters worth of gas. Once a ship has been

14:55positioned in a vessel berth—of which Sabine Pass has three—and once the ship’s tanks have

14:59been cleaned and prepared to take on the freezing liquid, loading arms are then bolted onto the

15:03ship and the filling process begins while crews monitor ice build up on the adjoining pipes. If

15:08the ship’s tanks have already been cooled, filling will take up to about 15 hours. This process needs

15:13to be fairly quick, as Chenaire reported that it filled 423 cargoes in 2022, and 425 in 2023.

15:21Once the liquid natural gas is on the move, it’s now the job of tanker operators to monitor its

15:25freezing cargo and minimize loss on account of off-boiling. There are two main categories of

15:30LNG tankers—those with independent tanks, like the recognizable Moss-style with its spherical tanks,

15:35and those with the less distinguishable integral tank—where the tank functions as a part of the

15:40hull. The former is older, deals with less sloshing—a danger that can damage tanks or

15:45increase boil-off inside the tank—and is reliably safe on account of the tank’s isolation from the

15:49hull. The latter is capable of carrying far more and because of this are becoming more prevalent,

15:54and are reliably safe on account of the tank’s pliability should the hull be struck. But both

15:59rely less on continuously cooling their product than just keeping it cold in the first place,

16:03as both tank structures are maximally insulated with more than 20 centimeters of foam and multiple

16:08barriers surrounding the tanks. Still, some boil-off is bound to occur, but rather smartly,

16:14that’s what powers the boat. And should the tank experience too much boil-off, there are systems

16:19in place to slow the process, whether by running gas back through reliquification, or by cooling

16:24the tank by spraying liquid from the bottom of the tank in the gap at the top. Keeping an eye on

16:29all this is a crew of about 20-29 members, with at least one cargo engineer focused on the

16:34composition of gas within the tanks specifically. Upon reaching its port of call, the process is

16:38effectively reversed, in a similarly labor and infrastructure intensive process with

16:43regasification equipment in place of trains. Ultimately, for as dispersed as users of natural

16:49gas are, and diverse as the uses of natural gas are, the process of making, moving, and

16:53regassing LNG is remarkably confined. Across the world’s two largest LNG producers, LNG exporting

17:00is confined to only seven active locations—6 in the US and just one in Qatar. And as for imports,

17:07Japan with the longest history of LNG reliance is home to around just 30 regasification plants.

17:14But like all fossil fuels, demand for natural gas is expected to soon peak. New buildings are

17:19increasingly being built with heat pumps, electric water heaters, induction stovetops, and other

17:24cleaner, more efficient electric alternatives. In fact, already, in New York City, for example,

17:29certain new buildings are banned from adding natural gas hookups. So this incredible network

17:34of pipelines and tankers will grow increasingly irrelevant in the coming decades. For now, though,

17:40it’s one of the world’s most fascinating interconnected distribution systems.

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The Logistics of Natural Gas

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