(Frank Smith, / October 6, 2013)

Three years ago, Frank Smith of Glen Burnie spent more than $44,000 to make the transition to solar power at his Cape Cod-style home, which was built in 1957.

That seemed like a hefty expense at the time, but significantly lower energy costs and tax credits from the state have helped offset that expenditure.

Now, he says, "I pay no electric bill whatsoever.

"I will recoup my entire investment in just seven to 10 years. Now, I'm also looking to put solar panels on the garage behind the house," he said.

This weekend, the Smith residence is one of the stops on the Metropolitan Washington Tour of Solar and Green Homes, which features 50 solar-powered homes in Maryland, the District of Columbia and northern Virginia. The tour started Saturday; Smith's house and others in the area will be open Sunday, Oct. 6.

Many of the homes on the tour — part of the larger American Solar Energy Society National Tour — are located along the Interstate 95 corridor between Baltimore and Washington, but the tour includes homes in Reisterstown, Glen Burnie, Owings Mills and White Marsh. The complete tour guide shows which homes are open Sunday, Oct. 6, and can be downloaded at solartour.org.

"We started with maybe a dozen homes in the D.C. metro area, but within five years we had grown to 35," said Chip Gribben, an organizer of the metropolitan tour. "Five years ago, we were up to 75 homes, but have since cut it back to 50 in order to better manage the event."

At a time when going green is considered pragmatic as well as environmentally conscious, the weekend event attempts to educate people about solar energy and the benefits of putting the technology in their homes.

"One of the great things about the tour is that you get to talk to the homeowners. You're not talking to someone who is trying to sell you something," said Margo Duesterhaus, an Ellicott City resident whose home is part of the tour.

The Duesterhaus residence includes solar panels on three sections of the roof, two panels for a solar water heater and another smaller panel for a solar attic fan. They also have solar daylight tubes at three locations on the main floor of their rancher, and other energy-efficient features throughout the house.

The solar-energy industry has grown considerably in the past two decades. According to the U.S. Energy Information Administration, there were 3,645 solar panels shipped at a cost of $2.90 per square foot in 1990.

By 2009, the number of panels shipped had risen to 10,511, while the price per square foot fell to $1.94.

The increasing popularity of solar energy is evident in Maryland, which was named a "Top 10 Solar State" by the Solar Energy Industries Association. The industry also provides a considerable number of jobs. In 2012, more than 2,000 people worked for about 100 solar companies in Maryland.

"Solar should be mainstream," Gribben said. "We're encouraging people to go for cleaner energy. When you see panels on a house, it should be normal."

When Smith bought his home in 1985, solar energy wasn't an option. He's pleased that the concept has caught on.

"The lack of an electric bill was a primary factor, but we also wanted to reduce our carbon footprint," said Smith, who also owns an electric car.

"You can't just throw panels on an old, leaky house. We also replaced appliances and light bulbs, and added 11/2 half inches of Styrofoam insulation," he said.

Thanks to this weekend's tours, many inquiring visitors could become converts to solar power.

"My next-door neighbor and one of my best friends got [solar energy] on my recommendation," Smith said. "It's the greatest investment we've ever made."

This year's Metropolitan Washington Tour of Solar and Green Homes continues through Sunday, Oct. 6. Guidebooks listing the homes on the tour, including a map and addresses, are available at area MOM (Mom's Organic Market) stores for $5 or can be downloaded for free at solartour.org.