The state’s largest utility reported that customers with solar are paying only a fraction of how much it costs to serve them.

Arizona Public Service has maintained that those with rooftop solar panels are not paying enough and, in effect, are being subsidized by other customers. Now the utility has filed data with the state corporation commission showing it costs about $118 to serve a typical solar customer. Of that, $67 is not covered by either the solar customer or the cost savings associated with the renewable energy. Put another way, solar customers only pay 36 percent of what it takes to supply them power.

Notably, the study does not include the so-called intangible benefits, such as decreased carbon emissions, which the solar industry generally points to as a critical part of the equation.

APS believes the numbers will bolster its efforts to raise fees during its rate case next year.