Are your discarded cereal boxes and banana peels renewable fuel? Newsday.com reports that the question has become relevant as New York state crafts rules that will mandate a heavier reliance on cleaner, sustainable energy sources.

Windmills, solar panels and fuel cells are considered likely to be on a list of renewable energy sources that will be compiled by state regulators _ a move expected to provide financial incentives that will help those generators. Operators of plants that generate electricity by burning municipal waste want to make sure they are on that list too.

That has set off a heated policy debate. Incinerator operators contending that they produce clean, sustainable energy are facing off against environmentalists and other opponents who say the plants burn too dirty and discourage recycling.

"Municipal solid waste is a sort of witch's brew of all sorts of garbage material, from processed paper to plastics to metal and glass," said Katherine Kennedy, an attorney with the Natural Resources Defense Council. " ... It's not a renewable item."

Regulators at the state Public Service Commission are on track to adopt rules requiring a quarter of the energy retailed in New York to come from renewables by 2013, following through on an announcement in January by Gov. George Pataki.

Regulators are now accepting comments from generators, utilities, environmental groups and other interested parties on how best to enact the state's so-called renewable portfolio standard. Among the many details being debated is whether municipal solid waste belongs alongside the likes of solar, wind, hydro and fuel cells.

"Making energy out of something that literally is garbage ... What better way to utilize a resource? Why should we let that resource be wasted?" asked Tom Rhoads of the Onondaga County Resource Recovery Agency, which financed a so-called waste-to-energy plant near Syracuse.

Maria Zannes, president of the Integrated Waste Services Association, said her members not only burn waste cleanly, but reduce the volume of garbage going to landfills. She said it's only fair to extend the same benefits to waste-to-energy plants as generators producing power from the likes of landfill gas. Incinerators have found allies among some of the municipalities that ship their waste to the plants. The New York State AFL-CIO wrote a letter to the PSC in May praising the economic benefits of waste-to-energy and urging its inclusion as a renewable.

Opponents contend the incinerators release into the air unacceptably high levels of pollutants such as mercury. State Attorney General Eliot Spitzer contends waste burning neither improves air quality nor provides economic benefits in the way that renewables like wind or solar energy do. "We do not characterize the incineration of waste in the same way that we characterize true renewables," said Spitzer spokesman Paul Larabee.

Derek Grasso of American Ref-Fuel said the company's two waste energy plants in New York have state-of-the-art air pollution control equipment, including acid gas scrubbers and fabric filters.

Ref-Fuel facilities in Niagara Falls and Nassau County produce, respectively, 50 and 72 megawatts. The state's 10 municipal waste burning plants combine to produce about 1 percent of the electricity consumed in New York, according to PSC documents.

The state currently gets about 18 per cent of its electricity from renewable sources _ the overwhelming amount of it from the New York Power Authority's massive hydro projects at Niagara Falls and on the St. Lawrence River.

Other states setting up renewable portfolio standards have reached different conclusions on whether to include or exclude waste energy.

The federal Department of Energy recognizes municipal solid waste as a renewable energy resource, according to a letter cited by Zannes. Opponents counter that the state Department of