Of the 94 elements found in nature, few are as polarizing as carbon
The widespread need for energy – whether to power cars, heat homes or run appliances – calls for a lot of fuel. In the United States, that usually means fossil fuels such as coal and gasoline. Their combustion releases CO2 to the atmosphere and contributes to global warming.
So the race to save our planet from ourselves sparked the green revolution. Earth lovers urged people to bike, walk or use cleaner fuels when commuting. Biofuels, hydrogen and electricity became the famed alternative fuels for our car-dependent nation.
But lurking under the hood is another contender that many forget: the Environmental Protection Agency-certified clean fuel, propane. The same gas that helps you grill up a spicy bratwurst or juicy burger can also send you speeding along the highway.
It has been making a lot of appearances away from the barbeque lately - from trade shows in Chicago and Indiana to energy summits in Washington.
On March 7, California’s Air Resources Board approved three new van types from U.S. auto manufacturer Roush, and the day after Roush premiered its new Ford F-450 heavy-duty truck. They can all run on everyday cooking fuel.
Propane is a hydrocarbon just like gasoline, meaning it is made of carbon and hydrogen atoms. It is the third most popular fuel in the U.S. for powering vehicles.
The EPA estimates that the average gasoline-powered car produces around 11,500 pounds of CO2 per year – and if propane-powered cars can reduce that number by the 30 percent many propane proponents mention, it’s nothing to scoff at.
While many propane fans claim it is the green fuel of the future, how green can this carbon-based fuel really be?
The price of propane
Two Jaguars and a truck emblazoned with Green Propane Power dominated the floor at January’s Mid-America Horticultural Trade Show. Their propane tanks were empty – the fuel "strictly prohibited at Navy Pier by the orders of the Chicago Fire Department," according to the Navy Pier website. But the Washington-based Propane Education & Research Council said that the fuel is permitted in several other venues.
When gas prices broke $4 a gallon a few years ago, Eric Hansen, owner of Competitive Lawn Service Inc. in Downers Grove, started shopping around for options. First he bought a couple mowers. Then a few more. Then a propane truck.
“We’re getting savings on this,” Hansen says. “If it didn’t work – guess what. We’d be in gasoline.”
Hansen says he has used personal CO2 testers on the mowers and seen a 60 percent reduction in emissions from his lawn equipment. Roush tests concluded that the propane-powered truck emits roughly 30 percent fewer greenhouse gases than one running on gasoline.
Tax credits and buying from private suppliers means Hansen can get propane fuel for much cheaper than gasoline, saving both cash and carbon emissions.
Industrial fleets such as taxis and delivery services often adopt propane. The switch is easier for fleets because they operate within a fixed range and can withstand the large upfront conversion.
Hansen started Green Propane Power after his difficulties finding information about purchasing and converting equipment to run the fuel. Despite the challenges, both Hansen and thousands of propane fans think propane is the wave of the future.
While Hansen and Roush have seen these numbers, scientific analyses of propane efficiency suggest different results for the average consumer.
In the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation Model, also known as GREET, scientists measured the cost of using various fuels such as propane. Andrew Burnham, a scientist from Argonne National Laboratory who worked on GREET, said that emissions were calculated from their source to the last emission to leave the tailpipe – also known as well-to-wheel measurements.
“For LPG from natural gas, we saw a roughly 17 percent reduction in greenhouse gases compared to gasoline,” he said.
When GREET scientists looked at LPG from petroleum, however, there was only a 9 percent reduction. Just over half of the United States’ propane comes from natural gas, which can be produced domestically.
Propane emits more carbon dioxide than natural gas, but not much more. Both vapors are cleaner than burning gasoline – and far cleaner than electric cars that get their energy from coal-fired power plants.
On average, propane produces 15 percent fewer carbon emissions than gasoline does – and that is for vehicles with propane-specific engines, rather than dual-engines or converted gasoline engines.
But you’re still producing countless tons of carbon dioxide.
“I don’t really see the condition under which it could be called green,” said Mark Ratner, professor of chemistry and materials science at Northwestern University. “It’s still making CO2. So it’s greener than some things, but not as green as others.”
He said the only way to be carbon-free was to switch to hydrogen as a fuel source.
While the carbon problem still remains, propane is appealing as a method to becoming independent from foreign oil, a vital energy topic.
“It’s not any more renewable,” said Stephen Ciatti, a scientist at Argonne’s Center for Transportation Research who did not work on the GREET project. “There’s no compelling reason to make people use it unless you’re using an energy security point of view.”
Propane has many aspects that make it difficult to work with. Because it is a gas, it is highly flammable and easily sparked if there is a leak. Propane is also normally a vapor. It has to be compressed to several hundred pounds per square inch before it becomes a transportable liquid.
Propane-lovers tout the cheap cost of the gas from major private suppliers who supply it well below the cost of what you pay for your barbeque propane arsenal. Currently gas is at $3.49 in the Midwest, while wholesale prices are half that, according to the U.S. Energy Information Administration. But Ciatti predicts that such low prices would not be the norm if more people were driving propane-powered cars.
“What happens when the demand increases?” Ciatti asked. “The price of propane is going to skyrocket.”
He also critiqued propane’s lower mileage and power, noting that most cars would only be able to travel 150 to 200 miles before needing a refill. Even though propane has the best infrastructure of alternative fuels, stations can still be hard to find. (Look at the interactive U.S. map below to see how many fueling stations there are in each state.)
“Tell me a better solution and I’ll take it,” Hansen said. “There’s a difference between a pie-in-the-sky research method that says we can do it and the reality that we could have driven this truck into the show on propane with 30 percent fewer emissions.”
It is with this in mind that members of the Propane Education & Research Council attempt to reach and teach citizens and, tangentially, lawmakers about their beloved fuel.
According to Brian Feehan, a PERC spokesman, advocates work not only to herald LPG’s benefits compared with other alternative fuels, but also to call attention to how much propane technology has improved.
Technological advances have ensured that converting to a propane-powered system wouldn’t necessarily mean sacrificing drivability.
“If you look at the development of technology in the automotive market and how advanced over the last 20, 30 years it has become, propane has also advanced in the last few years,” Feehan said.
Congress authorized the council in 1996, but the law prohibits it from political lobbying. Instead, its mission is to educate the public about propane.
“We work with our manufacturing partners to educate the potential base on how this new technology performs relative to alternative fuels and conventional fuels,” Feehan said.
The organization hosts a road show that tours the country, giving fleet managers the chance to test the products themselves.
“We’ll have a one day ride and drive, as well as an info session so they can come in and learn about the new technology,” Feehan said.
Lobbying is left primarily to groups such as Washington’s National Propane Gas Association, which has made a mission out of ensuring that propane is given equal footing with other alternative fuels being considered by the U.S. government.
“There’s a lot more in common that we have with natural gas than we don’t, though I think, in a lot ways, propane is the better option,” said Phil Squair, senior vice president of public and governmental affairs at the National Propane Gas Association.
Though the U.S. Senate has considered legislation to benefit alternative fuels, most proposed bills exclude propane and aim tax breaks at the natural gas and electric fuel industries.
“You’ve got a guy like T. Boone Pickens spending tens of millions of dollars lobbying and promoting CNG [compressed natural gas],” said Todd Mouw, vice president of sales and marketing at Roush Clean Tech. “They’ve got more money to do that.”
Pickens is a name that constantly seems to be on the lips of propane supporters. Though natural gas, propane and electric fuel technologies have similar environmental and economic benefits, the fact that natural gas and electric have received more mainstream attention is not lost on propane’s advocates.
“In the propane industry, you’ve got a couple of large players, guys like AmeriGas and Heritage and then it’s really a bunch of mom-and-pop distributors,” Mouw said. “There’s not a real concentrated push from a lobbying perspective.”
Roush is attempting to change that: it joined lobbying efforts in Washington and added a propane-powered Mustang to their drag racing lineup to highlight the fuel’s versatility.
“We wanted to showcase the performance of propane as well as safety,” Mouw said. “I think this showcases to the public that, ‘Look, it’s a very safe fuel, it’s a performance fuel and it’s why the rest of the world is using so much of it.'”
The propane industry paid for a third party, Energetics, to study the fuel’s greenhouse gas emissions. It found a 24 percent reduction compared to gasoline.
“It’s not zero emission, but it’s a heck of a lot better than gas or diesel,” Mouw said.
The way forward
Alternative fuels are still a work in progress and calculating the amount of carbon dioxide emitted is tricky. Currently, none of them can match gasoline for convenience. But the technology, even for propane, is still advancing.
Arun Basu, an engineer at the Gas Technology Institute in Chicago, said scientists in Japan and Sweden are mixing dimethyl ether, an organic compound that can be produced from biomass, and propane in an attempt to further lower carbon emissions.
Just a few weeks ago, Basu said, Vancouver agreed to be the test site for such vehicles.
In terms of a truly green planet, renewable fuels are the end goal fuels. While there are disagreements about the way forward, even PERC agrees:
“Something has got to be done to replace gasoline,” said Bill Polen, a company consultant. “We have to give ourselves alternatives.”
Vroom! While propane may not be the leading fuel in the United States, it is popular in other countries. South Korea tops the list of countries with the most propane-powered vehicles, according to data in a May 2010 study by Argonne National Laboratory.
Boom! Sometimes propane prices can go off the chart, according to scientists at Argonne National Laboratory. They found in data from the “Clean Cities Price Report” that suggests changing seasons can impact the price and availability of the fuel.
Zoom! Got a propane vehicle? Thinking of getting one? There are about 3,000 liquid petroleum gas fueling stations around the nation, but some states have more than others. Texas leads the country, followed by California, according to the U.S. Department of Energy.