by Ken Kolker | The Grand Rapids Press Thursday September 25, 2008, 11:40 AM

Press Photos/Paul L. Newby IIKendall College of Art and Design students, Sofia Ramirez, 17, and Scott Whitworth, 19, sign their names inside their footprints on the 350-foot petition during a Michigan Clean Energy Now event at Rosa Parks Circle on Thursday morning.

350 is the number of parts per million of CO2 (in our atmosphere) that must lower our emissions to in order to slow global warming. 350 is the red line for human beings. The most recent science tells us that unless we can reduce the amount of carbon dioxide in the atmosphere to 350 parts per million, we will cause huge and irreversible damage to the earth.

GRAND RAPIDS — A 350-foot banner bearing the footprints and signatures of several thousand people, many of them children, was wrapped around Rosa Parks Circle in downtown Thursday to send a message: The state should ban new coal-fired power plants to slow global warming.

A coalition of mostly environmental groups, known as Clean Energy Now, unveiled the banner today at a press conference and said they had collected more than 25,000 petition signatures. They planned to present the petitions to Gov. Jennifer Granholm on Friday.

They will ask her to issue an executive order to block construction of coal-fired plants. The state has 19 coal power plants with as many as eight new facilities planned, including a 78-megawatt plant in Holland and an 800-megawatt, $2.3 billion plant proposed by Consumers Energy in Bay City.

The new plants "threaten to take the state backwards with 1950s, coal-fired energy," said Jan O'Connell, energy issues legislative organizer for the Sierra Club chapter of Michigan. "They are moving us in the wrong way."

The environmental groups say the plants contribute to global warming and threaten the health of Michigan residents. The new plants also would reduce the state's potential for a new "green economy" and could cost thousands of jobs building renewable energy sources, such as windmills, the environmental groups said.

Aquinas College student and volunteer Liz Leduc helps hang a 350-foot petition at a Michigan Clean Energy Now event at Rosa Parks Circle on Thursday morning.

The Sierra Club hasn't taken a position on a proposal by the Holland Board of Public Works to inject carbon emissions deep into the ground instead of into the atmosphere. The BPW is competing for a $150 million federal grant for the project. However, environmental groups say the technology is untested and the federal government hasn't established rules for burying carbon.

Last year, 10 environmental groups gathered in Lansing to demand the state regulate CO2 emissions from coal-burning power plants across Michigan. They also demanded the state issue a moratorium on construction of coal-fired plants.

The groups pointed to a U.S. Supreme Court ruling that found CO2 produced by burning fossil fuels is a pollutant that should be regulated. The EPA regulates other pollutants, such as mercury and acid-rain-causing sulfur dioxide, but CO2 emissions are not regulated.

The Grand Rapids area's carbon footprint has shrunk in recent years -- by 14 percent in the first half of this decade, according to a recently released study by a Washington, D.C., think tank.

The area tied with Youngstown, Ohio, for the biggest decline among the nation's 100 largest metropolitan area.

Still, the Grand Rapids area has a bigger per-person carbon footprint, a measure of fossil fuel use, than most of the nation's big cities, including New York and Los Angeles. The study attributed that to a suburban lifestyle that requires commuters to use highways to get around.

The Consumers Energy J.H. Campbell plant in West Olive is, by far, the area's leader in carbon emissions, exhaling nearly 9 million tons of carbon dioxide last year, according to EPA reports.

Consumers Energy officials have taken steps to reduce emissions. They started switching to cleaner coal taken from Wyoming and Montana in the late 1990s. Three-quarters of its coal is western, with the rest from the Appalachians, which produces hotter-burning but dirtier coal.

E-mail Ken Kolker: kkolker@grpress.com