New autogas tank designed with space-saving, weight-reduction features

January 10, 2014 By    

In his 42 years in the propane industry, Jessie Johnson has shaped his mind to process how propane equipment and technology are supposed to work.

But then something comes along that forces him to rearrange his thoughts and accept a new way of thinking – something like a conformable propane autogas tank made from aluminum, scheduled to arrive in the United States this month.

As vice president of sales and marketing for Blossman Gas, Johnson is tasked with uncovering new opportunities that could benefit the progressive Mississippi-based propane retailer, its Alliance AutoGas network, as well as the industry. His research led him to a New Zealand company called Propane Performance Industries (PPI) and managing director Andrew Rodwell.

“I thought I had seen and heard everything,” Johnson says. “When [Andrew] started describing what he was doing with the tanks, I had to step back and think about what he was saying. It was so different from what I was used to.

“The whole concept of an autogas tank being aluminum and conformable really stretched our imagination.”

On top down under

PPI’s big breakthrough came in Australia, first with the aftermarket and then with an OEM.

In 2009, General Motors’ Australian division approached PPI about incorporating the tanks in a popular six-cylinder family and fleet vehicle called the Holden Commodore, Rodwell recalls.

About three years later, the first LP gas-powered Commodores hit the Australian market, and more than 4,000 of them are in operation today, he adds. PPI continues to ship more than 200 28-gallon tanks a month to Australia.

“A conformable tank design is adaptable to the available space under the vehicle floor, resulting in major efficiency gains in mass, usable fuel volume and range,” the Society of Automotive Engineers in Australia said in recognizing GM Holden on the project.

The technology that allows the notable fuel-tank flexibility was borne from the American space industry and acquired by PPI, according to Rodwell.

While the tank in the Commodore fits under the vehicle floor, its variations in size and shape allow its installation in creative spaces, depending on the application.

“The market in America is a fleet market initially, so the product is capable of being used in any application whatsoever – police, UPS-type delivery fleets, food delivery companies, school buses, long-haul trucking,” Rodwell says.

The tanks are designed to increase fuel capacity by filling in a space more efficiently, as well as reduce weight, especially when they replace multiple-ganged steel tanks set up to achieve a particular fuel capacity, the company says.

Rodwell cites one example, with an OEM light truck customer, in which the aluminum tanks provide 12 percent more fuel capacity and 28 percent less weight than three combined steel tanks. Weight reduction with aluminum is typically about 30 percent less when compared to a single steel tank, according to the company.

“[In instances] where the steel tank system has to be three individual tanks with hoses and pipes welded between them, ours is a single tank, one integrated unit, and you don’t have the air spaces that exist between tanks that sit side by side,” Rodwell says.

He compares tank configurations to a briefcase – rectangular in shape, flat and wide. Like a briefcase, a tank can sit on its base as an edge mount, flat as a horizontal mount or on its end as a vertical mount. A taxicab company owner, for example, could gain about 30 percent more trunk space for luggage, with no loss in fuel capacity, by standing the tank on its edge behind the rear seats of the vehicle, Rodwell says.

The company lists tank configurations with 9- and 12-inch heights. Depending on the width and length required, the range in capacity is significant. In the U.S. shipment, tank sizes range from 17 gallons water capacity (30 inches long, 15.5 inches wide, 12 inches high) to 98 gallons (70 inches long, 34 inches wide, 12 inches high). Rodwell says PPI can build tanks to any length.

“Rather than a round cylinder, think of it more like a rectangle with rounded corners,” says Gary Shepherd, director of the motor fuel division at Stanford LP Gas in Midland, Mich.

“The technology itself is nice – the physical mass of the tank is less, so when we add our fuel, our payload, you are actually starting out with less total weight added to the vehicle,” Shepherd says. “That’s always a good thing from an engineering standpoint.”

In addition to helping fleets convert fuel systems to propane, Stanford LP Gas designs and builds brackets for fuel systems. It is assisting PPI with tank evaluations and prototyping to see what sizes work best in different types of vehicles.

“One of the obstacles we’ve worked for years to overcome is how to maximize the use of available space for fuel,” Shepherd says. “We already have quite an advantage over natural gas, but we just can’t sit on our laurels and not get this activity within our industry where it needs to be.”

Another advantage of aluminum tanks is their inability to rust, Shepherd notes.

“Where we are in northern Michigan, salt is used on the roads, and those metal tanks have a tendency after two or three years to start looking pretty nasty,” he says. “Aluminum is much more resilient to outside corrosive factors than steel. It’s aesthetics. Why are we even worried about that? Because our competition worries about that all the time.”

First U.S. shipments

PPI is planning to ship 120 tanks to the United States and distribute them among seven customers that comprise a range of applications.

“We have customers fitting tanks into police vehicles, light trucks or delivery vehicles, and heavy-duty trucks,” says Rodwell, who forecasts PPI’s annual U.S. tank sales to reach 2,000 in the first year.

Rodwell says the police fleet wanted to remove weight from the rear of the vehicle to improve high-speed handling, aided by baffles inside the tank to reduce fuel sloshing, and add space for equipment.

California-based Alt Gas Technologies is receiving a handful of tanks that it wants to install on long-haul heavy trucks and farm tractors using a propane diesel injection system. The system, called the Diesel Magnum and which can be placed on any piece of diesel-powered equipment, displaces a portion of the diesel fuel with propane or natural gas.

“We have to find space on a truck to put a 50-gallon or so tank, and that’s not always easy,” says Stuart Solomon, the company’s founder and CEO. “Andrew’s tanks are ideal because we believe [most of them] can be stood up behind the cab of the truck.”

With the farm tractor, Solomon says the conformable tank can be placed on the roof.

“We’re confident, if they produce the way they are showing us, they’re the answer as far as space goes,” Solomon says. “They are not going to be as inexpensive as a standard tank, but over time they will probably get production costs down when demand goes up.”

While the concept of aluminum fuel tanks is not new, PPI is building its propane tanks structurally stronger and making them available on a larger scale, Shepherd says. And PPI is boasting compliance with U.S. regulations, including NFPA 58, and constructed to ASME code.

Manufactured in China through a highly automated process, the conformable, aluminum tanks cost about 10 to 15 percent more than a steel tank, but they become more cost competitive when replacing multiple steel tanks, Rodwell says.

Blossman Gas, meanwhile, is receiving an initial order of 30 tanks that it plans to test in various applications and show customers how they might work in their vehicles.

“We look at everything that comes on the market as an opportunity for us to make improvements to our program – and obviously for the industry,” Johnson says.


Why now?

Andrew Rodwell, managing director for Propane Performance Industries, believes the time is right for his company’s conformable, aluminum propane autogas tanks to hit the U.S. market for three key reasons.

“There is now a significant gap in the price of LPG versus gasoline, a gap that has been sustained and is expected to continue,” he says. “Gas companies now put mobile filling stations in fleet depots, which helps gives fleet users onsite availability and control of their fuel source. And thirdly and critically, the LPG systems are highly reliable, whether vapor or liquid systems. The injectors, the regulators – all the componentry – is now as reliable as those used on gasoline systems. All of that is giving the market confidence. It means it’s the right time for us.”

Photo courtesy of Propane Performance Industries

About the Author:

Brian Richesson is the editor in chief of LP Gas Magazine. Contact him at or 216-706-3748.

1 Comment on "New autogas tank designed with space-saving, weight-reduction features"

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  1. Great article, Brian. The possibilities are great for a conformable tank like this. My main question (compliance with ASME Boiler and Pressure Vessel Code and NFPA 58) appears to have been answered in your article.