FAQs

What does resource recovery mean?What does resource recovery mean?

Even after recycling materials, your garbage contains valuable resources. Capturing those resources and converting them into energy is what “resource recovery” means at a Waste-to-Energy facility.
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MRRA_Logo_TallWhat happens to your garbage at a Waste-to-Energy Facility?

After your hauler picks up your garbage, the hauler delivers it to a Waste-to-Energy facility where it is dumped on the floor or in a pit and either processed into fuel or fed directly into combustors to create electricity or steam. Emissions are carefully controlled and monitored to limit air pollution. Ash from the combustion of the garbage is managed in a landfill. Only 10% of the volume of your original garbage becomes ash, the rest becomes energy.
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What are the environmental benefits of Waste-to-Energy?

  • A source of renewable energy
  • A reduction in greenhouse gas emissions
  • Increased recycling
  • Cleaner environment

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Are Waste-to-Energy facilities environmentally friendly?

A Waste-to-Energy facility provides locally produced, renewable energy. Greenhouse gases are reduced as well as other harmful emissions. Producing energy from garbage conserves land for future generations and keeps our waters clean.
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Do Waste-to-Energy facilities release large amounts of harmful air pollution?

The sophisticated environmental control system employed at Waste-to-Energy facilities is extremely effective in minimizing pollutant emissions. In the United States, Waste-to-Energy facilities comply with regulatory standards more stringent than those imposed on coal-fired plants. Releases of dioxins and furans are 99.9% below levels in the mid-1980’s and recycling programs and other pollution prevention strategies keep mercury and other contaminates out of the fuel stream. Finally, as an alternative to landfilling, Waste-to-Energy prevents emissions of methane, a gas with many times the global warming potential of CO2. Even landfills that capture and flare methane or convert it into useful energy release significant volumes of this greenhouse gas over their lifetime.
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Do Waste-to-Energy facilities emit Mercury?

Do Waste-to-Energy facilities emit Mercury?Mercury moves through the environment as a result of both natural (volcano eruptions) and human activities. Human activities that are most responsible for causing mercury to enter the environment involve the use and consumption of products containing mercury and disposal into the waste stream or wastewater system. Waste-to-Energy facilities in Minnesota have been working hard to reduce mercury air emissions. Since 1990, Minnesota’s Waste-to-Energy facilities have decreased their mercury emissions by over 90%. Counties have assisted in this effort by implementing mercury recycling and reduction programs.
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How Does Waste-To-Energy reduce greenhouse gases?
When solid waste decomposes, it creates methane which is at least 23 times more potent than C02 in term of its impact on greenhouse gas production and global warming. Waste-to-Energy facilities eliminate that production of methane and reduce greenhouse gases.

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Fewer greenhouse gas emissions compared to landfillsGraph of emissions by source.
Source: Kaplan,P.O., J. DeCarolis, S. Thorneloe, Is It Better To Burn or Bury Waste for Clean Electricity Generation?, Environ. Sci. Technol., 2009, 43 (6), 1711-1717

What are the other advantages and benefits of resource recovery?

What are the other advantages and benefits of resource recovery?

  • Removing and recycling materials from trash that were not separated at the home or business.
  • Treating or processing the trash to make it non-hazardous, non-infectious and less harmful to humans or the environment.
  • Reducing the volume of the waste requiring final disposal, thereby reducing the amount of land needed for landfills.

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Is Municipal Solid Waste a renewable source of energy?

Is Municipal Solid waste a renewable source of energy?

  • Minnesota defines Waste-to-Energy (WTE) as a renewable energy source for meeting the State’s renewable standard of 25% by 2025.
  • Waste-to-Energy is sustainable.
  • Waste-to-Energy is “home grown”.
  • Waste-to-Energy reduces methane emissions from landfills and, thus, greenhouse gases.
  • Waste-to-Energy offsets the use of fossil fuels such as coal and natural gas to create electricity.
  • Waste-to-Energy contributes to healthy fuel diversity and reduces reliance on foreign sources of energy.

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How much renewable energy is produced at Minnesota’s Waste-to-Energy facilities?

Minnesota’s nine facilities convert the energy from waste and generate over 100 MW of electrical generating capacity, enough to serve the electrical needs of over 75,000 homes. Some of the facilities in Minnesota also produce over 150,000 lbs/hr of steam for heating and cooling and for use by local manufacturing and processing industries.
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How much more renewable energy does a Waste-to-Energy facility produce as compared to a landfill with gas recovery?

Minnesota’s Waste-to-Energy facilities have all operated for over twenty years producing 25 times more renewable energy than the same quantity of garbage disposed of in a landfill with landfill gas recovery. Landfill gas capture produces only 20 kWh of electricity per ton of waste as compared to 520 kWh of electricity per ton of waste produced by a Waste-to-Energy facility.
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How does burning garbage in a Waste-to-Energy facility compare to using a burn barrel?How does burning garbage in a Waste-to-Energy facility compare to using a burn barrel?

Burn barrels burn trash at low temperatures and are extremely polluting. They are estimated to be the largest source of dioxins, a very toxic and carcinogenic group of pollutants. Just one family using a backyard burn barrel will emit more dioxins per year than a 200-ton-per-day Waste-to-Energy facility.
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Do Waste-to-Energy facilities recycle?Do Waste-to-Energy facilities recycle?

Counties that participate at Waste-to-Energy facilities have extensive recycling programs. Nonetheless, recyclables often remain in the garbage received. Waste-to-Energy facilities help remove these recyclables as part of their operations. Some facilities have a MRF or materials recovery facility designed to remove recyclables (ferrous, aluminum and cardboard) prior to combustion. Other Waste-to-Energy facilities remove ferrous from the ash and recycle it.
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Will recycling rates be lower in communities served by a Waste-to-Energy facility?

Recycling is a vital component to a sustainable waste solution. Studies show that Waste-to-Energy facilities complement recycling efforts and communities participating in Waste-to-Energy facilities in Minnesota typically have higher recycling rates.
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Can combustor ash be utilized?

Yes, however it is not widely practiced in the United States at this time. Testing has confirmed that the ash is not a hazardous waste. The leachate, or water passing through the ash, almost meets drinking water standards.
In Europe, combustor ash is not allowed to be deposited in landfills, therefore it is widely utilized. Bottom ash is primarily used in asphalt mix, but also in road base and berm applications. Fly ash is treated and reused in building materials or deposited safely in old salt mines.
Beginning in 2000 in Minnesota, Polk County has performed six waste combustor ash utilization projects which includes one currently under construction.  Three projects used the ash as a amendment in asphalt mix.  Three used the ash as a substitute for the clay binder material in Class 5 base construction.  In total approximately 33,500 tons of screened ash have been utilized with the majority of this incorporated in Class 5 materials.  As a conservative measure all ash amended materials were totally encapsulated with virgin asphalt and Class 5 mix.  The CSBUD allows a substitution rate of up to 25%. The waste combustor produces an average of 6000 tons of ash per year. Currently, other Minnesota facilities are studying ash utilization options.
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How much landfill space do Minnesota’s Waste-to-Energy facilities save and how much electricity do they generate?

Sending garbage to a Waste-to-Energy facility saves valuable landfill space.  Minnesota’s facilities take in the equivalent of nine Target Fields full of garbage each year. The facilities put our garbage to work, producing electricity to meet the electrical needs of over 75,000 homes as well as providing heating and cooling for industries and process steam for manufacturing.
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Is landfilling a better waste disposal option?

Energy recovery represents a more productive use of non-recyclable MSW components, and it offers clear environmental advantages over landfilling. Some European and Asian nations have adopted WTE technologies as key elements of integrated resource management plans while banning or severely restricting landfilling due to concerns over land use requirements, greenhouse gas emissions, and groundwater contamination.
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What are the economic impacts of Waste-to-Energy facilities to the State?

Over twenty years ago over $400 million public dollars were invested to build Minnesota’s nine facilities. These facilities can easily operate for another twenty years. Waste-to-Energy facilities’ annual direct payrolls are over $20 million. These facilities also create hundreds of additional jobs statewide in engineering, trucking, laboratories, supplies and maintenance personnel.
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What is RDF?

In Minnesota, there are two RDF or refuse derived fuel processesors where raw garbage is reduced in size, ferrous and aluminum and heavy materials are removed and the remaining material is combusted to produce electricity.
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