The renewable energy industry is growing quickly in the U.S. as utilities transition from fossil fuels to cleaner energy, like wind and solar power. In some places, renewable energy faces opposition.
The Wisconsin NERC warned Wednesday that parts of the upper Midwest face a "high risk" of energy emergencies under certain conditions, such as extreme heat or unexpected generator outages.<br/><br/>
As the energy feeding the regional electricity grid changes from coal to more renewable, a big spike in demand could cause a power shortfall, the grid regulator says.