Surveying the US Waste-to-Energy Fleet
Archeologists studying ancient human societies often look to trash disposal sites of early civilizations for clues to help identify the resources and activities of humanity’s initial advancements. Trash, or municipal solid waste (MSW), from antiquity has proven valuable to illustrating the evolution of humans and how our ancestors managed waste streams. The methods of managing MSW today continue to evolve and demonstrate societal demands for certain resources.
Since the Industrial Revolution, MSW management strategies have focused on simple disposal in landfills or out at sea. Over the past half century, as energy and raw material costs have increased, the recovery of products and energy from MSW has grown considerably. In 1960, the recovery rate from MSW was around 6 percent, according to U.S. EPA estimates. Today, an estimated 35 percent of MSW is reclaimed through recycling, composting and conversion into usable energy.
According to the most recent estimates from “The State of Garbage in America” by Columbia University and BioCycle, 6.8 percent of MSW finds its way to waste-to-energy (WTE) plants in the U.S., where it is transformed primarily into process heat and electricity. Radiocarbon dating analysis of WTE emissions and ash has determined that roughly two-thirds of what constitutes MSW originates from biomass. As a predominantly biomass input, MSW-fed power plants are considered a part of the biomass power industry's fleet of grid-connected power plants. There are currently 71 operating WTE plant in the U.S., according to Biomass Magazine data.With 2,476 MW of nameplate capacity, WTE plants make up 40 percent of the operating biomass power industry’s generating capacity.
Conversion of MSW into renewable power is a waste management strategy with uneven dispersion across the country. In states where land values and heightened regulations discourage the siting of landfills, there are more WTE facilities. Five of the top 10 states for power generation from MSW are located in the Northeast, where land for disposal sites comes at a high cost and with stiff siting regulations. Florida, where a high water table inhibits the construction of landfills, has the most WTE power facilities at 11 and a combined generating capacity of 541 MW. Next year, Florida will add a 12th WTE power plant in West Palm Beach, which will represent the first WTE plant built in the U.S. in over a decade.
At its height in the late 1980s, the WTE sector built 11 plants each year. Between 1986 and 1990, 39 plants came on line to supply hundreds of megawatts of biomass power to the grid and mitigate the growing burden of MSW on local landfills. Federal energy policies under the Public Utility Regulatory Policies Act supported the growth of independent renewable power producers, like many of the WtE and other biomass power plants that were deployed in the ‘80s and early ‘90s. Municipalities possessed control over the flow of the MSW that was generated within its boundaries. Known as flow control, municipalities were able to manage their MSW by guaranteeing feedstock to a WTE plant that provided regionally reliable renewable power, jobs and a financial presence in the community.
In 1994, the U.S. Supreme Court strongly influenced the future of MSW management in what became known as the “Carbone decision.” The court declared municipal flow control laws that “deprive competitors, including out-of-state firms, of access to a local [MSW]” in violation of the commerce clause and unconstitutional. Without guaranteed feedstock at a guaranteed price, growth in the WTE sector declined through the ‘90s and into the early 2000s. Higher energy prices in the mid-2000s led to the expansion of a number of existing plants but no new plants were constructed. “It’s simply economics and policy,” explained Ted Michaels, president of the Energy Recovery Council, when asked about the fluctuation of the WTE sector. Over its lifetime, the WTE industry has grown agile enough to accommodate a changing market. Michaels says higher energy prices, increased adoption of sustainable waste management practices, and supportive climate change science has, and will continue to, encourage reasonable financing and productive policy.
Since the mid-2000s the amount of MSW generated has plateaued, and even gone down in some studies. The recovery of energy and materials from MSW is continuing to advance and diversify. Composters, E-waste recyclers, and, to a smaller extent, community-scale digesters have entered the MSW recovery arena. Advanced biofuel processors, such as Ineos at its plant in Vero Beach, Fla., aim to broaden the demand on MSW with liquid biofuel conversion technologies. Covanta Energy Corp., the largest WTE producer in the sector with a total grid-connected nameplate capacity of 1,256 MW, is positioning itself to offer a suite of MSW management services, from organics diversion for biogas production and E-waste recycling. James Regan, director of communications at Covanta, acknowledges the quickly evolving environment around MSW, explaining, “By coupling digestion, various forms of recycling, and WTE, we not only set ourselves up to maximize sustainability outcomes, but also handle the evolving needs of our customers.”
The historians who, one day, look back on the current era will likely not have to go through our trash heaps to figure out how we lived and what we valued as a society. If they did, they would see a rapidly changing industry around MSW management. With only 35 percent of MSW currently removed and reutilized, there is considerable feedstock in the MSW stream for the expansion of the WTE sector along with recycling, composting, digestion and other emerging industries that vie for a portion of the MSW pie. The question that remains is, will political and financial determination align to chart the industry's evolution?
Author: Kolby Hoagland
Maps and Data Manager, BBI International