Supporters say a ballot measure requiring that utilities get more of their electricity from renewable sources would make Michigan a leader in clean energy and create jobs.
Opponents say it would cost electric customers more money and make it harder to provide reliable energy.
On Monday, opponents with the Clean Affordable Renewable Energy (CARE) for Michigan Coalition plan to ramp up statewide efforts to defeat the issue. They argue the requirement doesn't belong in the state constitution.
The Michigan Energy Michigan Jobs coalition disagrees. It says Michigan will fall behind other states if it delays increasing the requirement.
The ballot proposal would require electricity suppliers to obtain 25 percent of their power from wind, solar, biomass or hydropower by 2025, up from the current 10 percent by 2015 requirement.
Copyright 2012 by ClickOnDetroit.com. The Associated Press contributed to this report. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.