Wheelabrator’s Hudson Falls facility in Washington County, New York Credit: Wheelabrator |
Waste to energy technologies have played a crucial role in helping Europe divert a significant amount of its waste from landfill, while reducing greenhouse gas emissions from both decomposing wastes and fossil fuel power generation. While some states in the U.S. have embraced the technology, much more needs to be done to develop an integrated national approach to waste management, where recycling, composting and waste to energy technology complement one another.
by Matt Kasper
According to the 17th Nationwide Survey of MSW Management in the U.S., the country currently generates almost 390 million tons (354 million tonnes) of solid municipal waste (MSW) per year – that’s seven pounds (3.2 kg) per person per day. It is commonly collected from homes and businesses on a weekly basis, and is usually sent straight to landfill.
Many states have the physical space to continue to landfill their waste. What’s more, some waste has to be transported to landfills several hundred miles away, further exacerbating its carbon footprint.
Though waste is not something the general public actively think about on a daily basis, specifically as it relates to climate change, the U.S. must begin developing policies to limit the environmental consequences of its disposal.
There are already some efforts in place to help manage waste generation. While MSW generation has significantly increased over the past decades, partly as a result of population growth, the country has also seen tremendous improvements in recycling and composting efforts. For example, in 1960 the U.S. recycled only 5 million tons (4.5 million tonnes) of waste, but today is recycling and composting more than 90 million tons (81.6 million tonnes).
This increase is largely a result of many state and local governments introducing recycling requirements, as well as incentives to recycle.
But there is another option that could help stem the flow of waste, and thus pollution emissions, but that has not been significantly utilised – waste to energy (WtE).
As the U.S. population continues to increase, greenhouse-gas emissions (GHG), specifically methane from landfills, will also rise as more waste is generated. Only very recently, scientists in Hawaii found that the amount of CO2 in the atmosphere jumped dramatically to a record high in 2013. America’s ‘business-as-usual’ plan has the nation on the wrong path. Federal legislators need to begin to find more ways to decrease the amount of GHGs in the atmosphere, and a plan that combines increases in WtE, recycling and composting would be a good start.
Cutting ghg emissions
States can have both WtE and recycling strategies that are compatible. Indeed, communities using WtE technology have an aggregate recycling rate above the national average. Currently, recycling and composting actions together decrease the country’s 390 million tons (354 million tonnes) of MSW to 296 million tons (269 million tonnes). However, a nationwide waste standard which stipulates mandatory levels of waste to be processed at WtE facilities and landfills and that incorporates recycling goals, could reduce this number even further.
According to the EPA, for every ton of waste processed at a WtE facility, approximately one ton of emitted CO2equivalent is prevented. This is because it is prevented from generating methane as it would at a landfill, and because metals are recycled instead of landfilled. Additionally, electricity generated offsets the GHGs from fossil fuel power generation.
The European Environmental Agency (EEA) notes that increasing rates of recycling and WtE will decrease the amount of greenhouse gases a country emits. Following an EEA study, the European Union adopted proactive waste policies, including the promotion of recycling and WtE as alternative waste management strategies. In fact, the European waste sector achieved a 34% GHG emissions reduction from 1990 to 2007, the largest pollution reduction of any industry in the EU.
The EPA and EEA are not alone in recognising the benefits of recovering energy from waste. The Intergovernmental Panel on Climate Change called WtE a “key [greenhouse gas] mitigation measure”, and the World Economic Forum included WtE in its list of technologies likely to make a significant contribution to a future low-carbon energy system.
LFG Recovery versus WtE
Landfills in the U.S. use different technologies to help decrease emissions. One method to use landfill gas to energy (LFG) technology. Of the 1900 landfills in the country, all of which are covered by the EPA’s air emissions and solid-waste management regulations, around 560 use techniques to capture methane and generate electricity. But even those equipped with methane recovery systems generate significant emissions for a number of reasons.
First, methane collection does not occur over the duration of the emission cycle. Landfills are not obligated to collect gas immediately, nor are they required to collect it for the entire period during which methane is being generated.
The EPA’s Waste Reduction Model, which tracks greenhouse-gas emissions from different waste management practices, estimates that when waste in landfills begins to emit methane, only an average of 34% is recovered to produce electricity. Another 38% of methane is flared and the remaining 28% experiences no recovery whatsoever. Consequently, landfills are the third largest contributor of anthropogenic methane emissions in the country.
Second, the efficiency of gas collection varies over time. A 2012 report prepared by the EPA and consultants, ARCADIS U.S., states: “Most of the existing data that is available to evaluate fugitive emissions from landfills is based on flux box data. These measurements do not account for the majority of losses found at landfills and therefore can potentially understate the emissions that escape to the atmosphere. With the increased interest in improving greenhouse gas emission inventories and strategies for emission reductions, there is a need to better quantify landfill gas collection efficiency.”
To better understand emissions from landfills, the researchers undertook source-measurement approaches and concluded that the methane abatement efficiency ranged from 38% to 88%. In other words, the landfills studied are only capturing an average of 62% of methane emissions, despite the 75% default gas-collection efficiency recommended by EPA’s guidance for emission inventories.
Diversion tactics
In order to reduce GHG emissions, waste must be diverted from landfill and sent to WtE facilities, after significant recycling and composting efforts have occurred. In fact, the EPA scientists concluded that sending waste to WtE facilities is the better option not only for generating electricity, as the technology is capable of producing ten times more electricity than LFG to energy technology, but also because GHG emissions from landfills, even those with optimum conditions for capturing methane and turning it into electricity, are two to six times higher than those of WtE facilities.
Landfill is the most commonly used disposal option in the U.S., accounting for 69% of total waste disposal. Some local governments, however, have begun to send waste to WtE facilities, totalling 7% of total waste disposal.
This 53 MW facility helped Lee County win SWANA’s 2011 Gold Integrated Solid Waste Management Excellence Award Credit: HDR |
A typical WtE plant is able to generate about 550 kWh per ton of waste, while complying with all state and federal standards. This process has led many to recognise WtE facilities as a form of renewable energy technology. In fact, the Energy Policy Act of 2005, which authorised loan guarantees, tax credits, and energy bonds for technologies that avoid greenhouse-gas pollution, included it as a renewable energy resource.
Under the Clean Air Act, WtE facilities must use the most modern air-pollution-control equipment available to ensure the smokestack emissions of carbon monoxide, nitrogen oxides, soot, and mercury are safe for human health and the environment. All facilities are specifically subject to regulations under the EPA’s Maximum Achievable Control Technology Standards, which created emissions standards for industrial and commercial industries. Because of the high temperatures inside the combustion chambers, most pollutants do not escape through the smokestacks, but scrubbing devices are installed in all WtE facilities as another control system to limit dangerous emissions.
Costs v benefits
WtE plants do involve large upfront expenditures, which can be a hurdle when building a new facility. A new WtE plant typically requires at least $100 million to finance construction costs, and this could be doubled or tripled depending on the size of the plant.
However, hauling waste to landfills is expensive for large cities. New York City, for example, paid more than $300 million last year just to transport waste to out-of-state landfills. In these cases, WtE facilities could be immediately beneficial by saving governments money while generating jobs and local revenue. In other regions of the country however, it can be cheaper to send waste to landfills when looking at a short-term economic analysis, due to the amount of land available.
Arkansas has an average landfill tipping fee of $35 per ton and has a reserve capacity of more than 600 years. This is less than the U.S. average tipping fee of $45 per ton and also is below the average tipping fee at a WtE facility of $68 per ton.
Even so, on a long-term economic basis, WtE facilities cost less than disposing of waste in landfills due to returns from the electricity sold and the sale of recovered metals. Indeed, Jeremy K. O’Brien, director of applied research for the Solid Waste Association of North America (SWANA), states: “Over the life of the [WtE] facility, which is now confidently projected to be in the range of 40 to 50 years, a community can expect to pay significantly less for MSW disposal at a [WtE] facility than at a regional MSW landfill.”
The most sustainable and cost effective approach to limiting the amount of waste sent to landfills is avoiding its generation entirely.However, since significant reductions in the production of MSW is hardly likely to happen at any point in the near future, the U.S. should create strong policies to increase recycling and composting efforts and implement policies to increase the amount of waste sent to WtE facilities.
The U.S. currently has 86 WtE plants operating in 24 states. Those facilities are capable of processing more than 97,000 tons (88,000 tonnes) of waste every day. The New England region – Connecticut, Maine, Massachusetts, Maryland, New Hampshire, New Jersey, and New York – has 37 of those plants.Connecticut has the highest percentage of its waste going to WtE plants of any state – around 70% of its non-recyclable waste – with a recycling rate of around 25%.
According to Eileen Berenyi of the research and consulting firm, Governmental Advisory Associates, WtE in Connecticut contributes $428 million annually to the state’s revenue and has created nearly 1000 jobs.
Lessons from Europe
Despite the economic benefits of WtE facilities, the country as a whole is not taking advantage of the technology, especially when compared to Europe. Countries such as Germany, the Netherlands, Austria, Belgium, and Sweden have proved that recycling and WtE go hand in hand.
Babcock and Wilcox Vølund recently installed its largest DynaGrate® ever at a new 3000 TPD facility in West Palm Beach, Florida. Installation of one of the four sections can be seen here |
These five nations have the highest recycling rates in Europe and have reduced their dependence on landfills to 1% or below of waste disposal.
European nations have been able to achieve these rates because of the EU Landfill Directive, which allows different countries to implement their own programs to drive down the amount of waste sent to landfills, whether that involves increasing landfill fees or increasing recycling collection schemes.
Because of strong nationwide policies, the EU member states sent 19% less waste to landfills in 2011 compared to 2001. This ultimately decreases the amount of greenhouse gases emitted from landfills and helps fight climate change.
In order for the U.S. to begin reducing the amount of waste sent to landfill, increase recycling rates, and generate renewable energy, a municipal-solid waste portfolio standard must be enacted by Congress and applied nationwide in order to decrease greenhouse-gas emissions from landfills.
Further to this, Individual states should also include WtE in current renewable energy portfolio standards.
MSW portfolio standard
The U.S. should set a municipal solid waste portfolio standard that would not only increase recycling and composting rates, but also significantly decrease waste destined for landfill.
As many European nations have already demonstrated, recycling efforts must be included in any national policy in order to reduce the level of waste sent to landfill.
A few U.S. states have already established MSW strategies. For example, both California and Florida have enacted a 75% target for recycling and composting combined by 2020.
Establishing incentives for recycling, such as providing homes and businesses with free recycling containers in conjunction with free collection for recyclables, as well as creating a market for recyclable materials is also paramount to achieving those standards.
Specifically, an executive order requiring federal government agencies to purchase goods and materials with recycled content would help to establish a market for these products.
By learning from what some states have successfully implemented, a U.S. nationwide standard should be created that mirrors what the European Union has established.
Include WtE in renewable portfolio standards
States’ adoption of renewable energy standards, which require electric utility companies to produce a portion of their electricity from renewable resources, has been a driving force for clean energy. The 29 states and the District of Columbia, which have such standards, also include landfill gas as an eligible technology, but only 21 states and the District of Columbia recognise WtE as an eligible technology.
Maryland has shown leadership in this area by raising WtE from a Tier II to a Tier I technology – the same level that solar and wind energy are on – in the renewable portfolio standard.
Other states should look to Maryland and Connecticut and adopt similar policies or seek to modify existing waste management policies so as to reduce incentives for, and reliance on, landfills and complement their renewable portfolio standard goals.
Importantly, states should modify their renewable programs so they are consistent with the solid waste hierarchy. While the solid waste hierarchy identifies landfills as the least preferred method for managing waste, landfills including ones with methane-gas capture are typically placed on equal or higher standing in renewable programs than WtE.
Both waste to energy, and recycling and composting efforts, are a win-win for the U.S.
The U.S. must begin developing national policies that incorporate all of these technologies in an integrated approach to deal with the waste management problem. Doing so will ultimately reduce emissions that cause climate change.
Matt Kasper is a special assistant for the energy policy team at the Center for American Progress.