Most of its revenue comes from operating incineration facilities that serve a secondary purpose as power plants that burn trash as fuel.

After starting as a public utility holding company it became a diverse conglomerate which had holdings in manufacturing, horse and greyhound racing, real estate, food, maritime transportation, arena management, and entertainment until its 2001 restructuring into a strictly energy business.

[10] In 1955, Ogden purchased Commercial Filters Corporation, an electronics and plumbing firm, and Luria Brothers & Co., an iron and steel scrap business.

Eimco manufactured filtration equipment and American Foundry & Machine made iron and steel castings.

[23] In 1968, Ogden acquired Soros Associates, which designed and developed bulk handling and port facilities.

[30] Ogden's entertainment division provided concession, merchandise, maintenance, cleaning, security, parking, and facility management services and concert promotions.

The company planned on constructing a 2,500-seat conference center, a 65,000-seat stadium, a 12,000-seat indoor arena, and a hotel/casino on the site of the abandoned horse track, however, lack of support led to Ogden selling the property in 1998.

[40] In 1999, it acquired several water parks, including Wet'n Wild Inc.[33] Ogden entered the energy-from-waste business in 1983, when it acquired intellectual property rights to the Martin GmbH incinerator technology commonly used in Europe, and a method of hazardous waste disposal.

[46] In 1998 Ogden sold its aviation catering business to SC International Services, an Onex Corporation subsidiary that also owned SkyChefs and Caterair.

[50][51][52] In 2001, Ogden's name was changed to Covanta, a portmanteau of cooperation and advantages, to represent its focus on energy.

[54] The bankruptcy was prompted by the California electricity crisis and the economic downturn following the September 11 attacks.

[57] That same year, 20 banks agreed to provide $463 million in financing to help the company get out of bankruptcy, restructure, and sell itself.

[54] In 2005, Danielson sold Ogden's interests in casinos, hockey stadiums, and other areas to focus on its energy-from-waste business.

[54] Later that year, Covanta acquired an energy-from-waste business called American Ref-Fuel for $2 billion.

[73] The remaining ash is rapidly cooled to prevent the formation of toxic compounds, then goes through additional processing.

[73] Government agencies regulate and monitor Covanta emission stacks for harmful toxins.

[76] A study by Columbia University said if waste-to-energy was as popular in the United States as it is in Europe, the U.S. would reduce carbon emissions by 264 million tons annually.

[68] However, many environmentalists are skeptical about Covanta's claim that the steam emitted from a plant's furnace does not contain toxic materials.

[68] Some environmentalist distrust government monitoring of Covanta's emission stacks, and have lobbied for more regulation.

[74] Additionally, Covanta has been cited numerous times for exceeding air pollution standards.

[77] For example, one Covanta plant in New Jersey was fined for violating emission standards;[78] in 2010, a related lawsuit was settled for $875,000, which was used for a local green space program.

[78] Covanta works with local governments to safely dispose of unwanted prescription drugs.