DTE Energy is lowering its fees on renewable energy and it should save customers about $90 million a year.
Residential customers will stop paying $3 per month and start paying 43 cents.
The Sierra Club and Clean Water Action were thrilled to hear it, claiming they've said all along that investing in wind and solar power is cheaper than initially thought.
Now they want DTE to stop using coal.
"We don't mine it here in Michigan, you know, it's from blowing off the tops of mountains in West Virginia, or shipping it all across from Wyoming. That's $1.4 billion a year that leaves our state" said Eric Keller, a protester.
They say this is another way to make the utilities less dependent on a single source to generate power.
DTE declined to speak with us for this story.