Waste-to-energy and conversion technology: Thoughts on where we are today

The network of traditional waste-to-energy (WTE) facilities, consisting of mass burn and refuse-derived-fuel- (RDF-) fired plants, is shrinking in the U.S. At the start of the millennium, there were 97 operating facilities with an estimated total capacity of approximately 98,000 tons per day (TPD). Since that time, 22 facilities have closed, and one new facility has opened, leaving 75 operating WTE facilities with a total capacity of approximately 94,000 TPD. This trend will most likely continue—particularly for smaller facilities—as the initial terms of their power purchase or steam agreements expire.

Competitive landfill tip fees and low wholesale energy pricing contribute to the contraction of traditional WTE facilities. The growth of the “zero waste” philosophy also has affected public opinion and acceptance of these facilities. The related “zero waste disposed” trend has gained significant traction lately, comparing WTE facilities to landfills and encouraging increased recycling and producer responsibility to divert waste from disposal. It is inevitable that unless the traditional WTE industry makes some technological changes, advancements or reinvents itself, the U.S. market will continue to decline.

WTE operators need to include technical advancements to fulfill the U.S. Environmental Protection Agency’s waste management hierarchy, such as maximizing material recovery prior to energy recovery. We must recognize that many of the technologies on the market are complementary and best suited to managing different portions of the waste stream at various stages of recovery and can contribute to the transition to a circular economy. Examples include new preprocessing technologies to divert previously unrecoverable waste from landfills or recover resources to create fuel products with a higher market value than simple electricity such as syngas, liquid fuels or chemicals.

Over the past several years, there have been signs in the WTE marketplace that waste processing, material recovery and energy recovery technologies may be working together. At Sierra BioFuels, based in Storey County, Nevada, and the Wasatch Integrated Waste Management District’s mixed waste processing facility in Davis County, Utah, municipal solid waste (MSW) is processed, recyclables are recovered and a portion of the postprocessing material is converted to a fuel product. As announced July 6, 2021, Fulcrum BioEnergy completed construction of the Sierra BioFuels Facility in Reno, Nevada, where approximately 11 million gallons of “zero-carbon syncrude” will be produced annually to be used as aviation fuel or other similar transportation fuels.

Combining waste processing technologies in this way is not a new concept. In Europe, mechanical biological treatment facilities have been used for decades. These complex facilities incorporate solutions to remanufacture recyclables, recover materials and energy from organics and produce RDF for energy generation. Additionally, these facilities improve upon the traditional, linear approach to waste management.

An even better approach to waste management is implementing circular economy principles by developing resource recovery parks, sustainable business parks or eco-industrial parks. These parks incubate various local businesses, manufacturers and “zero-waste to landfill” programs. They also:

• reduce greenhouse gas emissions by decreasing the amount of methane released;
• increase recycling and decrease the need for raw materials;
• produce sustainable economic impacts, including job creation and associated spending within the community;
• support energy independence through the production of fuel from MSW;
• offer a local, flexible solution to waste management rather than passing the burden along to other communities; and
• help support disposal security for areas threatened by this.

We must embrace the global trend of complex and multi-faceted solutions where land disposal is no longer the default destination for discarded items. Our nation’s approach has been that landfilling is fine unless something better comes along. We need to reinvent the industry to harness all the technologies that process MSW for advanced users as the default, reserving land disposal only for those materials for which there is no value in reuse and no methods yet discovered to recover or recycle them.