Minnesota utility regulators Thursday dismissed a complaint filed by solar developers against Xcel Energy, deciding not to investigate a controversial grid management policy that has restricted small rooftop arrays and larger community solar gardens.
The state Public Utilities Commission voted 4 to 0, in this instance, to stick with Xcel's judgment of when grid congestion would threaten system safety.
"I do believe that it is a high bar and should be a high bar ... for this commission to make a ruling on the company's reliability actions over their objections," said Commissioner Matthew Schuerger.
In September, the Minnesota Solar Energy Industries Association — along with a coalition of developers, customers and advocacy nonprofits — filed the complaint accusing Xcel of breaking the law when it set the restrictions in 2022. The group argued Xcel is exacerbating longstanding capacity problems on the company's power distribution network, claiming the utility cuts off 20% of space unnecessarily.
Xcel, however, says community solar is a major source of that congestion, prompting its "technical planning standard" meant to reserve some space on its power lines as a buffer.
When more energy flows onto Xcel's system than customers can use, it can lead to an excess power balance that risks equipment damage and failure. The company maintains it can use its engineering judgment to take action to head off that possibility.
Utilities traditionally transmit power by way of generating plants that are connected to transmission lines. But energy from rooftop and community solar flows back to Xcel for use elsewhere on the grid. This sends power both ways on the feeders and substations that handle power distribution.
Once an area reaches capacity, it's up to the solar developer — or customer hoping to build a rooftop array — to pay for infrastructure upgrades to the overall grid system because of state law and policy. Some have reported potentially $1 million estimates from Xcel, which will not hook up those projects until it is paid.