What many people fail to realize is that the decision to incorporate natural gas vehicles into a fleet is just a starting point. Before the vehicle acquisition process can even begin, there are important questions that must be asked and answered, questions such as whether to build a facility or rely on public infrastructure and what type of fuel to use: compressed natural gas (CNG) or liquefied natural gas (LNG). And even these decisions, it turns out, have any number of variables that can, and must, influence the final choice.

The first question, of course, is the type of fuel to use. CNG is a more effective fuel for regional operations while LNG is more appropriate for longer hauls. Regardless of the fuel choice, many of the considerations are similar with only the storage and delivery system of the fuel differing.

For fleets that decide to go the public route, i.e., utilizing available natural gas facilities at travel stops or filling stations or at partner companies, the most important questions include proximity, cost and type of fueling system.

“The first thing you need to do is [assess your needs],” says Kirk Honour, CEO of FirstCNG, a provider of natural gas solutions. “Are drivers going to be driving around a lot or coming home to the [terminal] at night?”

Public necessity

According to Tom Liutkus, vice president- marketing & public relations for TravelCenters of America, even those fleets that choose to build their own facility will likely need a public fueling option at some point.

“This question is very individual and best answered by fleets when they evaluate their own fueling terminal needs,” Liutkus says. “However, when fueling at public facilities, the fleets avoid the investment in tanks, environmental costs, and prevention and construction activities [while] concentrating on their core skill—delivering freight.”

TravelCenters of America is finalizing an agreement with Shell to provide LNG at TA and Petro Stopping Centers nationwide. That agreement, based on a memorandum of understanding signed back in June, would result in 100 LNG facilities with Shell. CNG would be a possibility down the road should the market develop for that fuel, Liutkus adds.

Lanes developing

Pilot Flying J has 33 locations up and running with natural gas—primarily LNG at this point—with 17 others under construction. Typically, those locations include three lanes capable of pumping 15 gpm, per lane, says Mark Hazelwood, president, Pilot Travel Centers.

“What we’re trying to do is develop a cross-country network where [locations] are about 350 to 400 mi. apart,” Hazelwood says, adding that pumping natural gas at a public facility is just an extension of a driver’s fueling habits. “It’s what drivers do today, and we have all the other amenities that drivers want.”

Pilot Flying J is installing 36,000-gal. storage tanks on-site to speed the fueling process for drivers (about 3½ to 4 min. per fill-up) and plans to offer special fueling programs for individual companies—programs not available to companies that utilize only their own facilities for fueling.

According to Hazelwood, the use of a public facility can save a fleet $2 million plus in installation costs for an LNG facility, in addition to ongoing maintenance and certification costs of that facility.

"The burden really falls on the carriers," he says. “We supply the product; the shipper might be pushing, but the ultimate burden is on the carriers.” Nopetro has opened the first of what it hopes will be 19 planned compressed natural gas facilities in Florida and Georgia. The station, in Tallahassee, FL, will service the Leon County School District, but will be open to the public. A portion of all the retail business sales will go to benefit the school district, Nopetro says.

Clean Energy Fuels is working with Pilot Flying J and others to spread the natural gas infrastructure across the U.S., planning a “natural gas highway.” The company is working to open 150 LNG stations built at “strategic truck stop locations along major trucking corridors” in the U.S., according to Clean Energy. Many of those stations will be built at Pilot Flying J locations.

And this is just a small sampling of the quickly growing infrastructure, which Liutkus believes is poised to really blossom in the near future. “Right now there are compelling reasons to consider natural gas,” he says. “There is a secure and long-lasting supply of a domestic fuel; it reduces our dependency on foreign sources of fuel; it is environmentally safer and greener; and there is currently a huge economic advantage for that investment when compared to diesel.”

Why pay retail?

One of the downsides to using a public facility is the retail cost of natural gas. Fleets that utilize these facilities are at the mercy of market pressures on the price of the fuel, and while it is much cheaper than diesel fuel currently, it may not stay that way. Owning a facility, though, can create a level of certainty in terms of cost control. There is also the opportunity to recoup some of the costs if you choose to open the facility for use by other fleets and/or the public.

“It you’re time-filling overnight, it’s a great idea [to open it to the public],” says FirstCNG’s Honour. “The reason it makes sense to do a retail setup is that even if you have to run some pipe, even if it’s for a single pump with two nozzles, [the cost to build it is not going to be much more] and you might make back $1 per gallon.”

Orrville, OH-based Smith Dairy Products is one company that recently opened its own facility, working with Vocational Energy. The station is also open to the public.

“The owners believe in CNG and they believe it is going to be big, not just for the dairy, not just for Orrville, but for the public,” says Rebekah Shipper, a Smith Dairy spokesperson. “Before we even did this, we did some educational forums with the public and business leaders to gauge their interest. There is a lot of industry in the area that has expressed interest.”

Outside interest

Shipper notes that during the first week the Smith Dairy facility opened, the company was contacted by Frito-Lay to inquire about using the station as a filling location for its natural gas vehicles traveling in the area.

Smith Dairy’s system, which Shipper says took just 90 days to install and is a fairly typical installation, taps into the Dominion gas line at the street. Smith Dairy installed a 3-in. line into its facility that allows the gas to flow into a “dryer” to rid it of particles before it enters the compressor and eventually into storage tanks.

There are, of course, a bevy of local, state and federal codes related to natural gas and piping that must be followed, and fleets need to check with their local municipalities and states to ensure compliance.

Before making the leap into the world of natural gas station owner, though, Honour has one key question that should be asked: How much fuel do you plan to use? “A good rule of thumb would be if you use 500 gals. a day,” he says. “As you move below that mark, it becomes more difficult to justify. You’re building infrastructure, but you’re adding cost to the vehicles themselves, so there is a sweet spot.”

If you choose to go the LNG route, it’s likely that the decision to use a public facility will be most feasible. However, LNG can be produced on-site by cooling available natural gas to -260 deg. F, but it must be stored in special cryogenic storage tanks. Typically, fleets using LNG will have it delivered and then store it on-site.

Cost influencers

Building a natural gas facility is not that difficult, says Honour, but the costs can vary widely based on region, price of natural gas, and the area’s electricity cost.

“They’re fairly straightforward to operate,” Honour says. “They’re fairly low maintenance, so by taking on a facility as an owner-operator, you’ll see the full benefit.

“The cost of the fuel includes the cost of the commodity—the natural gas itself—and that varies by region,” he adds, noting that the volume used will impact the final price. “There’s electricity to compress it; there’s maintenance, state tax, and federal tax. The biggest variable is probably the electrical cost and that’s probably about 25¢ of the [per gallon] cost.”

Once the decision to make the leap is finally made, there are other questions that need answering: What type of system (fast-fill vs. time-fill)? How many vehicles need to be filled? In what time frame and how many compressors are needed to accomplish this? What pressure is available from the natural gas provider?

“In most of the country, natural gas is [readily] available,” Honour says. “The downside is the pressure varies in the pipes, so the question becomes how much power do I need to pump the amount of gas needed? That’s going to affect the cost. It can make the system unaffordable. In general, the higher the line pressure, the cheaper the system will be.”

Honour says that lines producing as little as 20 psi can be viable for natural gas delivery, but higher pressures will reduce system installation costs.

What do you need?

What type of infrastructure is needed? There are just a few basic system setups, each coming with a compressor or compressors, depending on pumping requirements, and possible storage tanks, if that is the route chosen.

A time-fill system is the best option for a fleet that plans to fill its vehicles overnight. This system pumps only a few gallons per minute but is ideal for fleets without time constraints on the filling process. Because it requires less power to operate, it is also the cheapest option. According to Honour, a good ballpark figure for installation of a system that could fill 20 trucks per night would be around $2 million.

If time-fill is not an option because the flexibility to fuel vehicles throughout the day is needed, then a fast-flow system would be the way to go. This system generally pumps about 15 diesel gallon equivalents per minute, Honour says. Additional fill-time options exist and can be designed to meet specific needs.

“In order to build a system yourself, you need to know when the trucks will be filled and how quickly they need to be filled,” Honour says.

Time is money

Fast-fill systems use a combination of compressors and high-pressure steel storage vessels, reports NGVAmerica. Using multi-stage compressors, natural gas is boosted from the lower pressure delivered by the local gas utility up to 4,000 to 5,000 psi. When the fuel hose is connected to the vehicle, the dispenser is activated and gas flows from the higher pressure storage vessels to the vehicle’s onboard cylinders, the organization says.

In addition, dryers will have to be purchased. Because water content can cause blockages in natural gas fueling systems, dryers are needed to remove the water. The type of dryer needed depends on the water content level in the natural gas, according to ANGI Energy Systems, which specializes in the manufacture of dryers.

The other main component, and perhaps the most critical, to any natural gas system is the compressor. The size (horsepower needed) and number of compressors needed depend on the ultimate fueling goals. Additional compressors will be needed for fleets that want to fill multiple vehicles at the same time.

“If you design a system [with a single compressor] to deliver 10 gpm and you have two trucks filling at the same time, you’re only going to get 5 gpm pumped into each truck,” Honour says. “You have to calculate how much fuel you need over how much time you have.”

The final consideration is storage. Do you need it? Natural gas can be stored in aboveground pressurized vessels, but there are limitations.

“It’s not super efficient,” says Honour. “Let’s say you have 80 gals. sitting in a storage bottle and you send it to a dispenser. The maximum amount of fuel you’re going to get is 40 gals.” before the system will need to replenish itself.

The better option, albeit more expensive, is a compression on-demand system. This system requires no storage since it compresses the fuel as it is needed. “It requires more horsepower [to operate], but more fuel is available to use,” Honour says.

The decision to either install your own natural gas facility or utilize a public option is really a matter of individual preference. For fleets located near such a public facility, the lack of price control may outweigh the cost of maintaining their own station. In the end, though, Honour notes that fleet manager anxiety does not need to be a by-product of natural gas use.

“I think it’s not as scary as it sounds,” he says. “There are resources available. There are companies like mine that will help lead you through this.”

“If you don’t think you can do it on your own, don’t,” advises Smith Dairy’s Shipper. “Get together with other companies.” Plenty of fleets are finding that is the most viable option available.