Since announcing his intentions last February, Keares has been confronted by the expected cadre of opponents from the neighborhood, but also some he never unexpected: environmentalists.
The Brandywine Conservancy, one of the region's leading land preservation groups, has come out against his Coatesville Solar Initiative.
Turning the 46-acre forested tract into a field of panels - rising as high as 9 feet, and set in rows 12 feet apart - could dangerously increase storm-water runoff, the conservancy contends, and destroy vital wildlife habitat.
"We love solar energy. We love wind energy. It's just that it's a high price to pay to rip out these natural areas," said Wesley R. Horner, senior adviser for water resources.
"Solar's a great idea. But it's got to be put in the right place."
In Keares' view, this is the right place - especially given the proximity to the Coatesville Area School District's high school and administrative offices.
He's working on a deal to sell energy directly to the district, which has endorsed the project. By bypassing the electrical grid, Keares says, the school system could save $200,000 to $400,000 a year on energy costs, depending on the rate negotiated.
He also wants to supply power to the neighboring Coatesville Veterans Affairs Hospital, though formal dialogue has yet to begin.
Keares' company has several solar projects in its portfolio, including a 1.1-megawatt farm on a West Chester-area waterworks owned by Aqua America. The Coatesville Solar Initiative - for which he teamed with Solare America L.L.C., a solar-project designer with offices in Malvern and New York - would be not only his biggest, but also Pennsylvania's. For now, the largest installations in the state are about 3 megawatts.
Ironically, the very aspect of the Caln Township tract that makes it so attractive for solar production - steep slopes with great sun exposure - also exacerbates concerns about runoff.
The Carver Court Association, representing a development of about 100 homes at the base of the site, said residents feared flooding. Others raised concerns that their woodland views would be compromised.
The solar farm split the township's Board of Commissioners down the middle: A vote in June on whether to schedule public hearings on the project ended in a 2-2 tie.
The measure passed in a second vote the following month, when Commissioner Charles Kramer, who had been serving a military tour of duty in Afghanistan, returned to end the impasse.
Until just a few weeks ago, the board had been hearing testimony on whether the township should change the area's residential zoning to permit a solar farm.
The process has gone on long enough that the project lost a federal grant that would have covered 30 percent of the original $40 million cost. To qualify, construction had to begin by the end of December.
Keares now plans to fund the farm, in part, by using federal tax credits available for new solar projects.
He has tried to win over opponents with a modified proposal, and seems to have assuaged at least some of them with promises to move a portion of the panels off the steepest slopes and create a buffer of trees and plants to hide them from view.
In the process, the farm has been scaled back to about 30,000 panels producing 7.2 megawatts of energy. Projected to cost $25 million, it will pay for itself, Keares estimates, in 13 to 18 years.
His campaign for community support has also included consultations with state wildlife officials on how best to preserve habitat. And he has agreed to pay for the extension of a water and sewer line through the property and to cover the cost of connecting 28 homes to it - about $12,000 each.
On Friday, he also agreed to compensate Carver Court homeowners for any flooding caused by increased storm-water runoff, to rehab an aging recreation center, and to hire three or four residents to work at the solar farm.
But even before that, Keares had scored enough points to prompt homeowner Joe Clark to declare at a recent commissioners' meeting: "We're in support now. We have changed our minds."
The Brandywine Conservancy has not.
Because solar panels would inhibit rain from soaking into the ground, a high-functioning storm-water management strategy is crucial, the group contends. It has taken issue with Keares' system, which uses large mesh structures called filter socks to capture runoff.
"There's any number of things that could go wrong," resulting in catastrophic flooding for neighbors, said the conservancy's Horner, who lives near the site.
Something as common as a burrowing groundhog, he said, could tear one of the socks, which are filled with soil and usually used only temporarily during construction projects.
Even if it works perfectly, the system would be able to handle only half the runoff, according to an analysis by a consultant Horner hired.
The Caln Township engineer also has said that Keares' current proposal does not meet municipal storm-water requirements.
Keares contends the system can handle the runoff generated by a 100-year storm. "We're exceeding the requirements of the township," he said.
When the commissioners ended their hearings in mid-January, most put themselves in the undecided column - but not for long.
They are expected to vote on rezoning the site for a solar farm by the end of this month.
Contact staff writer Anthony Campisi at 215-854-5015, firstname.lastname@example.org, or @campisia on Twitter.