Tom Dennison, left, of Southern Maryland Electric Cooperative and SunEdison project manager Jay Marx at SMECO’s new solar farm in Hughesville. (Tin Nguyen/Maryland Independent)

Six weeks after the region’s first commercially operated solar farm went live, the Southern Maryland Electric Cooperative is so pleased with the results that it’s looking to build a second facility.

The 5.5-megawatt farm, which is up the street from SMECO’s Hughesville headquarters, started producing electricity Nov. 18, with 10 percent of its output going to power the co-op’s new engineering and operations center, also located nearby.

At maximum production, the facility will generate enough clean energy to power 600 homes and offset the pollution of 1,600 cars, SMECO officials say.

The $20 million project consists of 1,078 fixed arrays — racks holding 22 solar panels each — covering 33 acres of the 47-acre site, a onetime tobacco farm purchased by SMECO at the turn of the century.

The 23,176 American-made panels convert sunlight into direct current, which is collected in 132 small combiner boxes and carried underground to larger power inverters that turn the charge into the alternating current used to power homes and businesses.

From there, the power travels through a switch gear to transformers and out onto the grid.

State law requires that utilities generate 20 percent of their electricity from renewable energy sources by 2022. Of that amount, 2 percent must come from solar energy produced in Maryland, whereas wind energy can be bought from anywhere in the region covered by the PJM Interconnection, said SMECO President and CEO Austin J. Slater Jr. PJM is an electricity wholesaler that covers all or parts of 13 states and the District. The co-op purchases its wind energy from western Pennsylvania, he said.

Utilities that fall short of the renewable-energy goals must purchase offsetting credits or pay a penalty of $185 per megawatt hour, Slater said. The price of the credits is not determined by the marketplace but set between 80 percent and 90 percent of the penalty, he said.

The co-op determined that the least costly way to meet the state’s solar requirement was to build its own facility, at a cost of about $135 per megawatt hour.

It issued a request for proposals in spring 2011 and quickly received bids from 18 developers for 29 projects at various locations throughout Southern Maryland.

The state “created the demand, and now you’ve got manufacturers out there competing,” Slater said.

Solar company SunEdison submitted the winning bid for a project on the co-op’s farmland, and SMECO was able to secure a federal stimulus grant that covered 30 percent of the project’s cost.

Crews began clearing the farm in March. Five historic barns were leveled but first catalogued and photographed in records that will be available in state archives.

Construction began in earnest Sept. 1, when the first 15-foot piles were driven 11 feet into the ground, and was completed in November.

At peak construction, 55 workers were on site seven days a week, often 12 hours a day, installing the arrays in five separate sections.

“It’s assembly work, like at a factory,” said SunEdison project manager Jay Marx.

The long days were made shorter by the hospitality of the facility’s neighbors — Jimmy and Joanie Herbert, from whom SMECO originally purchased the farmland. The Herberts kept a 15-acre tract, where they live today.

“The Herberts were fantastic,” Marx said, adding that the crew appreciated the dinners and cookie baskets Joanie would prepare for them.

“I just wanted to do it. The guys were out of town, and it was nice to introduce them to things they’d never tried before,” Joanie Herbert said. “They were like a bunch of chickens coming to eat. It was fun.”

A frequent on-site guest during construction, Joanie Herbert has compiled four large photo albums cataloguing the project.

“To me, it was all exciting, digging holes in the ground and such,” Joanie Herbert said. “This was a very interesting project.”

“From start to finish, Jimmy and Joanie have been absolute pleasures to work with,” SMECO spokesman Tom Dennison said.

A member of the Hughesville Civic Business Alliance, Joanie Herbert described the solar farm as “nice and quiet” far preferable to the baseball stadium that was planned for the SMECO property in 2004. The stadium plan caused a local uproar and led to the eventual construction of Regency Furniture Stadium in Waldorf.

“This is a very sensitive community, and they take a lot of pride in their community. We took it to them before we did anything else,” Slater said. “They take some pride in the fact that they’re associated with state-of-the-art energy production.”

With no moving parts or motors, the arrays require little maintenance beyond a twice-annual check that the panels are working properly, Marx said. Low-growing grass has been planted beneath the mounted arrays and will only need to be cut three times a year.

The panels, which have a lifespan of at least 25 years, can withstand winds up to 120 mph; most of them had been installed when Hurricane Sandy swept over the region in late October, but the storm had no effect on the project, other than a few trees that fell toward the rear of the site, Marx said.

Originally projected to produce 8,733 megawatt-hours of energy annually, the farm now is expected to generate 9,220 megawatt-hours in its first year of operation.

Still, the facility will produce only enough power to meet SMECO’s escalating solar requirement for two years, so the co-op has begun looking for a spot in Southern Maryland to build another solar facility.

“We thought this process went very well,” Slater said. “It’s going to be tougher economics [without the grant] this time around, but we’re still going to go through the process, and I think we’ll be able to do it cheaper this time.”

Slater said the co-op chose to build the moderately sized facility, even though it would only fulfill its needs for a couple years, in order to take advantage of solar-power breakthroughs down the line.

“The technology is changing very quickly in this area, and we didn’t want to get too invested in 2012 technology,” he said.