JANESVILLE—A public-private solar power plant at the city of Janesville’s municipal landfill likely won’t get built anytime soon unless the cost and economics of such a project changes, a city official said.
Maggie Darr, operations director for the city of Janesville, said a consultant’s report heard by the city council last week provided “good news and bad news.”
The good news: It likely would be physically feasible to build and operate a 22-acre set of solar power arrays on a closed or capped section of the landfill.
But the bad news is that the vast bulk of project’s net cost—about $5.03 million—wouldn’t be recoverable under a 20-year operational model that assumes the city would sell power back into Alliant Energy’s power grid, according to a study that the city ordered this fall from Madison consultant SCS Engineers.
The plan calls for about 7,200 solar panels across 22 acres of landfill at a cost of $5.4 million.
The project would bring online an initial, 3 megawatts of solar production—a relatively small-scale project compared to many private solar projects that aim to develop hundreds or thousands of acres for solar use.
That would be just one of four potential landfill sites totaling about 80 acres in all that consultants said the city ultimately could develop for solar.
About a mile of fiber optic communications lines would be needed between the landfill solar site and Alliant’s nearest electrical substation.
The consultants came to this conclusion even after factoring in a possible public-private partnership with Alliant that would allow the parties to tap into a 22% state tax incentive aimed at offsetting depreciation of power generating infrastructure and equipment at the site.
The study’s outcome showed that at current reimbursement rates for municipalities selling back solar power to a utility such as Alliant, the city over a 20-year span would draw down on the city’s greenhouse gas emissions. But the city would only recoup about $370,000 of the initial $5.4-million cost of the project.
Darr said that if the city built out solar on other parts of the landfill, as they close over the next 5 to 10 years, the SCS study indicated that under current costs and energy reimbursement rates, the project would not create economy of scale for the city.
“Even in a good-case scenario we’d probably still not be making money at the end of the 20-year period,” Darr said.
Darr said it’s possible that in the future, if technology costs for solar continue to decrease, solar at the landfill could become more economically feasible.
Darr said she hopes that the outcome of the city’s review of solar at the landfill won’t curb residents or private commercial entities from hatching their own, private solar projects in the Janesville area.