By David Barer
For Texas Climate News
and Reporting Texas
Each day lumbering green trucks from Waste Management travel down Giles Road just northeast of downtown Austin, carrying thousands of tons of household waste to the Austin Community Landfill. Meanwhile, 130 miles away, black-and-white spotted Holsteins and tan Jersey cows pepper the countryside as they graze on pastures north of Waco.
Such landfills and dairy farms are ubiquitous in Texas. But few people in the state grasp what they have in common and why dairy producers might be jealous of another man’s trash. The organic waste produced on dairy farms and deposited in landfills ferments and expels one of the most treasured natural resources on the planet – energy in the form of natural gas.
But don’t expect trash or cow manure to replace hydraulic fracturing or other conventional means of natural gas production any time soon. Capturing and converting the gas into usable energy isn’t simple. Major landfill operators in Texas have found success, but dairy farmers have yet to discover a way to sustainably turn their manure into money, and it could be a long time before they do.
Several factors, including today’s rock-bottom natural gas prices, stand in the way of biogas – as methane produced by degrading organic matter is commonly called – becoming a widespread fuel source in Texas.
Capture of biogas didn’t begin in earnest until the last decade. It will never be a major portion of Texas’ energy portfolio, but utilizing biogas can help clean the environment, diversify energy sources and bring profit.
“Trash has to be put somewhere. If you can get energy from it, why not?” said Roy L. Orbach, director of the Energy Institute at the University of Texas at Austin. “You’re actually following the natural course of nature, which is where you have decay which produces gas, so it’s about as … natural a process as one could envision.”
A potent greenhouse gas
The benefits of capturing methane, the principal ingredient in natural gas, are two-fold. It’s a boon to those farmers and landfill owners who are able to harness its power, and it rids the environment of a potent greenhouse gas. Methane is 20 times more effective at trapping heat in the atmosphere than the carbon dioxide produced by human activities that involve the burning of fossil fuels.
Harnessing the methane emitted by dairy-cow manure could put a dent in American methane emissions if obstacles like the price of natural gas and the cost of an anaerobic digester – a system used to capture methane from manure and other bio-solids – can be overcome.
The natural gas market has been a victim of its own success, thanks in large part to technological advances in hydraulic fracturing, also known as “fracking.” The process involves drilling thousands of feet underground and injecting water laced with special chemicals under extreme pressure to free previously hard-to-reach gas and oil deposits. Fracking has led to a glut of natural gas on the energy market, with prices hovering around $3 per 1,000 cubic feet. That’s close to the price natural gas fetched 10 years ago.
“The very low price of natural gas – that has a huge impact on the electricity market and the competitiveness of electric entities in the state,” said Russell Smith, executive director of the Texas Renewable Energies Industries Association.
The energy market will have to change before farm owners can profit, according to a Texas dairyman who once had a digester built on his property. He spoke with Texas Climate News and Reporting Texas on condition of anonymity because of possible legal issues related to the project.
“Natural gas is going to have to get into $12 [per thousand cubic feet] and stay there, and oil needs to get to $150 a barrel and stay there, and the electricity costs need to go through the roof because it takes a lot of maintenance to operate those systems and the life span…is not very long,” he said. (Wellhead prices of natural gas have risen above $10 per thousand cubic feet on only a few fleeting occasions over the past four decades, according to the U.S. Energy Information Administration.)
The dairyman doesn’t see digester systems in Texas becoming profitable without subsidies and some extra source of waste.
“I know that there are some [digesters] working around the country, but this one,” he said, referring to his digester, “would never have operated efficiently enough without having some municipal waste … and some tipping fees [charges levied on waste received at a processing facility] involved in it too.”
Energy markets aside, the cost of a digester in itself is currently prohibitive. To install one on typical dairy farm can cost $1 million, with more complicated systems costing more, according to Darren Turley, executive director of the Texas Association of Dairymen.
The value of methane-capture systems goes beyond profits and lowering greenhouse-gas emissions. In the case of dairy farms, collecting methane protects water supplies as well. Manure can cause a handful of problems for water sources if it’s introduced in large, concentrated amounts like those originating from a dairy farm. The runoff can cause algal blooms, excessive phosphorous and a stench, among other woes.
“I think that everyone was hopeful,” Turley said. “To have an alternative energy that would help you get rid of your waste … it just seemed like the right thing to do, and I think it will be. It’s just not there yet.”
He added: “The few that have stepped out and been at the forefront of this technology have just had a struggle.”
Landfills: Profiting when farmers couldn’t
Where dairymen have failed to profit from methane, major landfill operators like Waste Management, the largest in Texas, have been successful.
All new landfills in America are required by U.S. Environmental Protection Agency regulations to use gas-capture systems. Waste Management and other landfill operators have gone further and installed gas-to-energy systems on older landfills. Those projects are profitable.
The financial success of Waste Management’s gas-to-energy systems at its landfills is due in part to its deep pockets and huge waste streams – the daily inflow of garbage. The Houston-based company can incur the large upfront expenses of building the infrastructure needed to capture methane, clean it and convert it into electricity. In Austin and other major metropolitan landfills, it also utilizes waste provided daily by hundreds of thousands of residents..
Deployment of gas-capture systems has been so lucrative for Waste Management, it created its own in-house development wing. The company began using third parties to build gas-to-energy systems. Today Waste Management is itself a third-party contractor building systems for other businesses, according to Wes Muir, who was the company’s director of communications when he was interviewed for this article.
In Texas, Waste Management has seven gas-to-energy systems producing 40 megawatts of electricity, enough to power more than 10,000 homes. A portion of the electricity generated at the Austin Community Landfill directly powers the Dell Computer complex, Muir said.
Compared to other renewable sources in Texas, 40 megawatts is a small number. The capacity of the state’s nation-leading wind industry tops 10,000 megawatts. And San Antonio, aiming to become a leader in solar power through its city-owned electric utility, has set a municipal goal of producing nearly 450 megawatts by tapping the sun.
Still, Waste Management’s gas-to-energy projects around the country, coupled with its waste-to-energy facilities, produce more renewable energy than all U.S. solar energy facilities combined, Muir said.
Texas uses and produces the most electric power of any state in the nation, with summer usage topping 67,000 megawatts. Because Texas is close to maxing out its available power, energy authorities were on the verge of instituting rolling blackouts during 2011’s record heat wave, according to ERCOT, the agency that oversees the electricity grid in most of the state.
Waste Management’s decision to build a gas-to-energy system in a given landfill doesn’t depend entirely on that landfill’s gas-producing capabilities. It also hinges on a community’s interest in diversifying its energy sources.
“If there is a very aggressive program to create a renewable energy portfolio in that community, then this is kind of a no-brainer,” Muir said. “We are bearing the cost of constructing and providing energy into their renewable energy portfolio for that community.”
“Renewable” … or not?
Some environmentalists who generally support renewable energy, however, find fault with labeling landfill gas a renewable resource. For instance, Andrew Dobbs, Austin program manager of the Texas Campaign for the Environment, believes organic waste material could be put to better use.
Dobbs said landfills should “dry-entomb” the waste in their landfills on a daily basis, meaning operators cover up the waste to prevent water and air from entering and accelerating organic breakdown. If all landfills used this process, gas production would be minimized. There are better uses for organic materials, he said, such as creating compost to invigorate nutrient-depleted Texas soils.
It’s fine to capture and use methane now being emitted by landfills, but that should not reduce the impetus to change waste-disposal practices so they yield less methane in the future, Dobbs added. If paper, plastic and certain metals are recycled, combined with separation of organics for composting, then only non-reusable items that don’t produce gas would be left, he said.
Dobbs summed up his argument this way: “If … we are saying, ‘Hey, things are great, we don’t have to worry about our trash anymore because we are making a lot of fuel off of it,’ that is, at best, putting a pretty face on a bad situation. At worst, it is perpetuating unhealthy habits for our society.”
Bringing about widespread change such as Dobbs advocates would undoubtedly be a lengthy process.
Nonetheless, Smith, of the Texas Renewable Energies Industries Association, sees a future for methane generated from bio-materials. With the state’s growing population and increased energy demand, he said, “Every source that we can come up with is going to have to be looked at. We are encouraging the powers-that-be to develop the diversification of the electric generation resources in the state.”
David Barer, an intern at Texas Climate News during the summer of 2012, has written for the Associated Press, the Austin American-Statesman and Reporting Texas, a digital media initiative of the School of Journalism at the University of Texas at Austin. Barer is a graduate student in journalism at UT.
Image credit: U.S. Department of Agriculture/Wikimedia Commons