Not long ago they were open trash pits that emitted unpleasant odors while devouring the financial resources of their owners. But today, it’s as if the princess of sustainability came along and kissed the frog of landfills, and now the frog generates profits rather than odors. But don’t blame the turnaround on magic. Instead, look to the technology of landfill-gas-to-energy (LFGTE) production.
With more than two decades of history and a well-developed marketplace in Europe, the LFGTE industry has outgrown its infancy, but thanks to North America and less-developed countries around the globe, the growth potential remains staggering. The marketplace demand for biogas technology will reach nearly $1.2 billion by 2016, according to BCC Research, Wellesley, MA. So let’s see what’s behind this industry’s growth, by starting with a road trip to Dry Branch, GA, where the pride of the town is an LFGTE project that demonstrates how sustainability can unify various groups.
The site is the Wolf Creek Landfill, and on Earth Day 2012, for its official debut, the landfill played host to the Environmental Protection Agency (EPA), a partnership of electrical cooperatives, plus numerous state and county dignitaries. The project was developed by Sustainable Energy Solutions LLC (SES), of Jacksonville, FL. SES currently has four LFGTE sites in Georgia, Alabama, and Louisiana. According to Bill Gibbes, president of SES, Wolf Creek’s financial success depended upon a 15-year power purchase agreement (PPA), and needed the cooperation of several0 resources.
NOTHING FOUND
“It’s always a challenge to put together a power purchase agreement in states that have no renewable portfolio standards, and Georgia does not,” says Gibbes. “We were fortunate to be able to work with Green Power EMC, which represents a 42-member electrical co-op that forms Oconee EMC, and we have agreements with 31 of the 42 members that are willing to pay a price that made the project work yet be reasonable for them to include some renewable energy in their voluntary programs for customers willing to pay more for green electricity.”
Assuring a consistent flow of methane was another challenge. Although SES had a projection for the methane output based on the characteristics of the landfill, such factors as the waste composition, rainfall levels, humidity, and other geographical issues could still affect production. “You can never take a projection to the bank,” says Gibbes. “I’ve seen projects where everybody assumed that it would be correct, and when we started up there was only enough gas for half the engines they’d ordered. So we wanted to get the gas flowing and verified rather than risk overbuilding the power production plant.”
The verification process lasted two years, but some of that time can be attributed to aligning the business partnership and the PPA. Gibbes notes that the methane flow was steady and has actually increased due to the landfill’s expansion. So there’s more than enough gas to fuel two GE Jenbacher J420 containerized generator sets, each rated at 1.4 MW electrical output. “We’ve been pleased with the J420 gensets and they have performed as they were described,” Gibbes adds. “The installation was straightforward and with containerized gensets they are delivered ready to go, other than hooking up the power, cabling, and gas lines. We took advantage of a long-term maintenance agreement that includes the overall maintenance and rebuilds.”
Reliable service and maintenance boosts hardware sales.
Jenbacher customers have a wealth of maintenance and monitoring options, according to Michael Wagner, marketing director, GE Jenbacher, Jenbach, Austria. “We offer long-term service agreements up to the lifetime of the equipment,” says Wagner. “And the controls over the last 10 or 15 years have made great strides. All of our installations have the capability of remote control from the plant’s facility, but also it can be controlled and monitored directly at a remote location. So if a company has 20 locations it can control them from one central operation, and we provide the operator and customer the opportunity to monitor and access his plant from our service center for online help.”
The LFGTE market has been a long-term success for Jenbacher. Wagner notes that his company has 25 years of experience in the combustion of landfill gas, with products installed in more than 1,400 landfill gas systems, for a total electricity output of about 1,400 MW delivered throughout the world. Europe represents one of Jenbacher’s oldest markets, but Wagner sees growth tapering off as stricter laws divert organic material from reaching landfills. But there are still plenty of opportunities in the North and South Americas, and especially in developing countries. “The United States has been a very important landfill-gas-to-energy market,” says Wagner, and there is great potential in Southeast Asia and Latin America.”
Often the potential is for very large projects such as the Loma Los Colorados Landfill in Chile. In April, 2012, GE announced an 8.4 MW upgrade that will bring the site’s total power output to 18 MW. The upgrade relies upon the same genset model used at Wolf Creek, the J420 containerized reciprocating engine gensets, each rated at 1.4 MW electrical output. In the LFGTE marketplace, reciprocating engines from Jenbacher, Caterpillar, Cummins, and others have been the overwhelming choice. However, turbine power generation designs are gaining traction.
Recent inroads from turbine companies include an order for two Solar Centaur 60 combustion turbines from Solar Turbines, a subsidiary of Caterpillar, that will produce 11 MW of electricity at the 2,200-acre Apex landfill, north of Las Vegas, NV. Moving down the scale, three 250-kW microturbines from Flexenergy, Irvine, CA, provided the City of Santa Clara, CA, with the ideal solution to replace a 2.5-MW reciprocating engine that had to be retired when gas production declined below the engine’s minimum requirements. Then, too, boilers are still an option. As far back as the 1980s, the Sanitation District of Los Angeles County’s Puente Hills Landfill complex fueled a 50-MW boiler/steam turbine facility, and still had enough gas to transport through a pipeline to nearby Rio Hondo College, for use in its fire-tube boilers.
Consultants Make a Difference
Shaw Environmental provides a variety of LFG and LFGTE services, ranging from generation and use analyses, operating systems assessments, and complete design-build services. Shaw’s subsidiary, LFG Specialties LLC, manufactures and installs LFG and LFGTE systems.
Landfills provide potential for capturing various forms of renewable energy. LFG has been proven to provide a stable source of fuel for electricity production, for use in industrial boilers or even pipeline quality gas. When LFGTE is combined with wind energy or solar energy at landfills situated in areas with these potential renewable energy sources, the landfill can be converted to a renewable energy park providing the owner with supplemental income following closure of the facility. Golder Associates’ 30-year history of providing waste management solutions allows the company to meet a variety of customer needs with a range of integrated solutions. Viewing landfills as energy parks is a particularly good example, not only because of Golder’s experience in the assessment, design, and installation of projects such as the Old Dixie LFGTE system for the Dalton-Whitfield Solid Waste Management Authority in Georgia, but also in its experience with wind, biomass, and solar systems in other venues throughout the world.
Pipeline Connections
In fact, transporting gas by pipeline is a growing trend for landfill operators. For example, if we return to another landfill in Georgia, not far from Dry Branch, the Seminole Road Landfill in DeKalb County is expanding upon its LFGTE project with the addition of a landfill-gas-to-compressed-natural-gas system. For the past six years, two Caterpillar, G350C Landfill Gas Low-Emission Generator sets with a combined output of 3.2 MW have been churning out electricity at Seminole Road, and it’s been both productive and profitable, says Billy Malone, sanitation director.
“As far as earnings, we’re getting from $100,000 to $105,000 per month at 98% capacity of the engines,” says Malone. “We’ve been operating the engines since 2006 and met the full return on capital investment sometime in our fourth year.” The Caterpillar engines also met Georgia’s tough NOX emissions standards of 25 tons per year. “Caterpillar showed that they could deliver at .5 brake horsepower, which would meet the number we were looking for in our permit,” Malone recalls. “When we did the testing the engines actually came in at .23 as opposed to .5, so they delivered a lot better in emissions numbers then we were anticipating.” Maintaining low emissions gave DeKalb the option of adding another genset to take advantage of their surplus gas, but Malone found that producing CNG offered some persuasive advantages.
“We know we can’t produce as much electricity as we have gas available so now we are producing transportation fuel and putting it in a pipeline and building a fueling station onsite to fuel our garbage trucks,” says Malone. “Making electricity makes sense to us, and it has a good bottom line, but natural gas for the pipeline also has a good bottom line, and making it for trucks probably has the best bottom line out there. Rather than paying $3.70 a gallon for diesel, we can make CNG at less than half that cost. We run 306 vehicles every day and we have converted 40 to CNG while we fuel up at private locations until our project opens.” The processing facility has a 2.9-year return on investment and the conversion of the trucks and the CNG equipment is about three years.
LFG to LNG plant at the Bowerman Landfill in Orange County, CA
Converting landfill gas to LNG or CNG is the wave of the future, according to Harrison Clay, president of Clean Energy Renewable Fuels, a subsidiary of Clean Energy Fuels, Seal Beach, CA. Clean Energy builds and operates LNG and CNG fueling stations, and recently announced a project with Waste Pro USA to build, operate and maintain a new CNG fueling station on Waste Pro property in Fort Pierce, FL, to support the company’s new fleet of CNG-powered trash trucks. Waste Pro recently announced an investment of $100 million for vehicles and fueling stations to transition a portion of its fleet from diesel fuel to CNG fuel. In the initial phase, the company expects to deploy 150 heavy-duty waste collection and recycling trucks.
“Look at the larger companies such as Waste Management, Republic, and Waste Pro, and you’ll see that they are all rapidly moving towards natural gas in their fleets,” says Clay. “They’re saving tons of money because the cost of diesel is 10 times when compared to a natural gas, and at those numbers it’s impossible to ignore. Moreover it’s domestic and clean fuel.” Furthermore, the long-term production looks good, as in Texas, where Cleanenergy is producing high-Btu landfill gas from the McCommas Bluff, TX, landfill-gas processing plant-the third largest landfill-gas operation in the United States. According to the methane output projections, McCommas may well qualify for social security benefits before it runs out of gas.
The city of Dallas opened McCommas in 1975, and it’s scheduled to close in 2042, but it has been estimated that pipeline quality methane gas could continue for approximately 30 years after the landfill closes. “We have a second site under construction at a Republic Services landfill outside of Detroit that should go online this summer,” Clay adds. “We are injecting pipeline-quality natural gas into the gas grid, and we anticipate that we will be providing increasing volumes of renewable natural gas to our existing vehicle fuel infrastructure for sale as LNG and CNG.”
The term “renewable” also has applications for blended products, so Cleanenergy can offer customers a percentage of landfill gas mixed with natural gas. “It’s even more environmentally friendly fuel than just straight natural gas,” explains Clay. “So if they want to lower their carbon footprint by fueling with blended product they could have a percentage such as 10% or 20% of their fuel as renewable natural gas.”
As the transportation of landfill gas by pipeline for use in vehicles continues to grow, it will be driven to a large extent by the refuse industry, but Cleanenergy also has its sights set on the long haul commercial truck market. However, the practice of transporting gas by pipeline isn’t limited to vehicle use. There’s also a growing trend in piping landfill gas to commercial and industrial sites. And we have at least one example of landfill gas powering a university.
The University of New Hampshire’s EcoLine project made news as the first LFGTE used as a primary source of power on a campus. Completed in May of 2009, EcoLine can provide natural gas for up to 85% of the electricity and heat used by the 5 million-square-foot campus. The project is a partnership with Waste Management’s Turnkey Recycling and Environmental Enterprise (TREE) in Rochester, NH, where methane is collected by a system of more than 300 extraction wells and miles of collection pipes. The gas is purified and compressed at a UNH processing plant at TREE, then it travels through a 12.7-mile-pipeline to UNH, where it replaces commercial natural gas as the primary fuel source at a cogeneration plant installed by the university in 2006, as a replacement for an aging boiler.
Total cost of the project, including construction of the pipeline and the processing plant at TREE, was $49 million. The university sells the renewable energy certificates (RECs) generated by using landfill gas to help finance the overall cost of the project and to invest in additional energy efficiency projects on campus. In addition, UNH sells power in excess of campus needs back to the electric grid. The excess power comes from a second turbine that puts 100% of its 4.6 MW output back onto the grid. It doesn’t have heat recovery on it at this time; neither does it run when cold winter temperatures slow down the production of methane at landfills. Nonetheless, the majority of fuel for the 8-MW Siemens turbine and CHP unit comes from landfill gas.
In the commercial arena, BMW began using gas from Waste Management’s Palmetto Landfill at its South Carolina automotive plant in 2003, to fuel four gas-turbine cogeneration units (4.4 MW capacity) and recover 72 MMBtu per hour of hot water. The turbines fulfilled about 25% of the plant’s electrical needs and nearly all of its thermal needs. Nearly 70% of BMW’s energy consumption comes from LFG, via a 9.5-mile pipeline. In 2009, BMW replaced the four gas turbines with two more efficient gas turbines with a total capacity of 11 MW.
Gas for Centralized Power
Pipelines also open up the market for landfill gas as a fuel for centralized electricity generators, as is the case with the Cedar Hills Regional Landfill in Maple Valley, WA. The King County Solid Waste Division contracted with renewable energy company Bio Energy LLC to generate usable energy from methane gas at Cedar Hills. The facility uses a quarter-mile pipeline for transporting the processed landfill gas to Williams Northwest Pipeline and on to Puget Sound Energy’s natural-gas-fired power plants.
At the Finley Buttes Regional Landfill, just south of Boardman, OR, it’s hot water, rather than gas, that gets piped to a commercial application. Finley has a combined heat and power (CHP) system, that uses three Caterpillar 1.6-MW 3520 gensets to deliver 4.8 MW of electricity, plus an abundance of hot water (100 therms per hour of 234°F heat). The installed cost of the system was $9.7 million, with a simple return on investment (ROI) of four years.
Lightning-Fast Paybacks
Fast ROIs of four to five years are common with LFGTE projects. The EPA’s Landfill Methane Outreach Program cites the fact that there are a variety of products to sell, including electricity, LFG, and Renewable Energy Certificates (RECs). Additional revenue is possible from tax credits and incentives, clean renewable energy bonds, greenhouse gas reduction credits, and energy cost savings. That’s a fairly respectable group of financial opportunities. However, Fredrick County, MD, didn’t take advantage of any of those sources in its LFGTE project. All it did was agree to let Energenic of Mays Landing, NJ, build an LFGTE project at the Reichs Ford Road landfill. County officials reported spending about $100,000 for their part of the development plan, and in return the county will earn a minimum of $280,000 per year from Energenic. Does that equate to an ROI of less than six months? Or is it a one-year ROI of 280%?
No matter how they’re calculated, such fast returns further demonstrate the value of landfill gas, and when a top executive from a company such as Microsoft starts talking about locating the company’s data centers at landfills, that value is clearly gaining in recognition. In April 2012, Christian Belady, general manager of Data Center Services for Microsoft, published his thoughts on a distributed energy scenario for data centers. It’s not unusual for larger data centers to exceed 100 MW in power demands, and Belady wrote that data centers located at landfills could use LFGTE as a renewable source of fuel for fuel cells.
Microsoft isn’t the first to float this methane-filled trial balloon, in fact: The Newton County Renewable Energy Business Park in Brook, IN, won an EPA LMOP Project of the Year Award in 2010 for executing a concept similar to Belady’s. The park gets 100% of its fuel needs from landfill gas transported through an 1,800-foot pipeline from Republic Service’s Newton County Landfill in Morocco, IN.
Apple Computers is another believer in the distributed energy scenario, and it shares Microsoft’s attraction for onsite fuel cells. The company announced a natural-gas-powered fuel cell project for its North Carolina facility, but to qualify as a renewable facility it must supplement its fuel with a portion of landfill gas or a similar biogas. Stationary fuel cells that can deliver megawatts of power have to convert methane to hydrogen in a process that’s done internally, and the conversion process does add a layer of complexity to the systems, along with a reduction in efficiency. But landfill gas may offer a solution to the problem.
Is Methane to Hydrogen the Next Step?
In mid-2011, BMW Manufacturing launched the initial phase of a program intended to validate the economic and technical feasibility of converting landfill gas into hydrogen for use in the company’s entire fleet of material handling equipment. The project again demonstrates the ability of landfill gas to attract the development of coalitions. The first phase of this million-dollar project was funded by the South Carolina Research Authority, a partnership of government energy agencies and other public and private sponsors. Also participating are the Gas Technology Institute, Ameresco Inc., and the South Carolina Hydrogen and Fuel Cell Alliance.
BMW credits its existing LFGTE program with reduced carbon-dioxide emissions of about 92,000 tons per year and savings of $5 million annually in energy costs. The company currently uses hydrogen fuel cells to power about 100 material handling vehicles in the North Carolina plant’s new assembly facility.
Clearly the opportunities for LFGTE applications are growing. But will the industry experience declining gas production from the diversion of organic waste, as referred to earlier by Michael Wagner, marketing director, GE Jenbacher? The question has stimulated a new round of research into the science of gas generation prediction, says Dr. Morton Barlaz, professor and head of the Department of Civil, Construction, and Environmental Engineering at North Carolina State University.
“If you’re looking at investing several million dollars in engines and apparatus to generate and transmit that energy, you need predictability,” says Barlaz. “The composition of municipal solid waste is changing as cities divert more paper to recycling programs. And as foodwaste recycling gears up, these things affect the amount of gas that the landfills produce. The major generators of gas in a landfill are paper, yardwaste, and foodwaste. As these materials are diverted, you might see a 20% decrease in the mass but a 30% or 40% decrease in the generation potential, depending upon what’s kept out of the landfill.” According to the EPA, yardwaste and food scraps make up about 27% of the MSW that reaches landfills.
Recycling and diverting organic materials continues to grow as a trend in the US. For example, the city of Seattle has attained one of the highest rates of recycling in the country, a staggering 50%. And recycling isn’t limited to MSW. Construction-and-demolition materials are seeing higher recycling rates, and the same is true of forestry byproducts.
In fact, one company, Air Burners Inc. of Palm City, FL, offers a line of Air Curtain Burners, also called FireBoxes, designed principally as pollution control devices. The primary objective of an air curtain machine is to reduce the particulate matter or smoke, which results from burning clean woodwaste, a procedure that occurs in forestry and landscape clearing. The company’s smallest machine burns at a rate of 1 to 2 tons per hour, the largest can burn in excess of 10 tons per hour. Future plans call for an electricity generating line of FireBoxes that utilize the heat energy from the wood waste combustion process to power an ORC (waste heat generator).
Foodwaste Breaks Away
Foodwaste recycling is growing into a separate industry from MSW. And even though Waste Management owns or operates 131 LFGTE projects that utilize foodwaste, the company recently participated in a conference designed to help the restaurant and hotel industry develop foodwaste recycling programs. Foodwaste is also highly sought after for anaerobic digesters designed to produce methane or synthetic gas derivatives, as is the case with a unique CHP project at the University of Wisconsin (UW)-Oshkosh, where the campus plays host to the first dry anaerobic biodigester, for producing biogas to fuel a cogeneration system.
Though traditional wet anaerobic systems are well established in North America, a dry system offers numerous advantages for a campus environment. The technology is well established in Europe, and the company supplying the system for UW-Oshkosh, BIOFerm Energy Systems, Madison, WI, has 28 operating installations worldwide.
The university expects the 370-kWh cogeneration plant to produce 4,183 MW of thermal energy and 3,071 MW of electricity annually. The system uses a 2G Optimus 370BG, built by Man Engine, a company recently acquired by Caterpillar, in part for its history of success with biogas fuel.
The Oshkosh system launched with four digester chambers, each with a processing capacity of 2,000 tons per year. The facility started out with about 6,000 tons per year and should reach 8,000 tons per year as the university gains experience and secures feedstocks. Feedstocks such as MSW and industrial food processing waste offer prime sources of methane.
Universities are developing sustainability programs, and recycling is a key element to the success of such programs. Moreover, many universities seek to establish links with their communities to broaden their spheres of influence in sustainability matters. But it’s difficult to quantify the overall impact of these programs, and by the numbers the task is staggering. In the US, for example, the latest figures (2009) from the EPA estimate that Americans generated about 243 million tons of trash, or 4.34 pounds per person per day, while foodwaste typically accounts for about 13% to 30% of MSW content, depending on the locale.
Let’s forego the final number and just say that, ultimately, landfills will experience some diversion of MSW, but the long-term impact to the industry has yet to be determined. So for the roughly 600 LFGTE sites currently recognized by the EPA, the future looks like one of delivering a renewable energy resource for industrial and commercial use, while delivering an attractive ROI to both private and publicly owned landfills.