JACKSON, MI – An automatic release of natural gas combined with high winds and hot equipment caused a massive Jan. 30 fire at Consumers Energy’s largest natural gas storage site, an internal investigation shows.

Consumers released a statement on Friday, April 5 about its findings after a two-month investigation. The Michigan Public Service Commission is doing an investigation exploring what happened.

Consumers worked with a third-party consultant on the investigation.

The fire at the Macomb County Ray Compressor Station prompted a potential natural gas shortage. The station holds 64 percent of Consumers’ supply. Record-low temperatures were recorded across the state that week, leading to record-high demand for natural gas.

Natural gas was released by a firegate system because the signal to the system was interrupted due to a grounding fault, said Katie Carey, director of media relations, in an email. That automatically triggered the gas to be released. The reason for the grounding fault and subsequent signal interruption is still under investigation, Carey said.

“Consumers Energy’s review found no evidence of failure to properly maintain our equipment,” the statement says.

The firegate system is designed as a safety measure to allow natural gas to dissipate into the atmosphere, rather than fueling a potential fire inside during an emergency.

Cold and windy conditions that day kept the natural gas just above the stack. The mixture with air created the flammable plume, which blew over to the neighboring plant and started the fire, Carey said.

“Under unique and extreme weather conditions, the process became hazardous,” the statement says. “We plan to address the issue at the Ray Compressor Station and implement new procedures across our natural gas fleet to further enhance resiliency and help avoid failure in these extraordinary circumstances.”

Michiganders were asked to lower their thermostats to 65 degrees via a statewide emergency text to cellphones and a late-night video from Gov. Gretchen Whitmer.

Nearly 100 businesses shut down production to conserve natural gas and customers decreased usage by 10 percent. Heat interruptions to homes and businesses could have resulted without the combined savings, Consumers executives said.

Correction: The headline in an earlier version of this story indicated outages resulted from the gas shortage. Outages were in fact avoided after customers answered the call to turn down their thermostats.