PALERMO — Paul Armstrong has been off the grid for more than 20 years.

The 52-year-old construction worker said it would have cost too much in 1994 to have Central Maine Power Co. run an electrical line to his property at 401 Marden Hill Road.

So he designed and built his 3,000-square-foot home, including a full basement, with the idea of generating his own electricity.

Over the years, he has installed solar panels, a windmill and a backup generator.

“I can see Mount Washington and Mount Katahdin when the leaves are gone. I got a couple-hundred-miles view,” he said. “When my ex-wife and I were considering solar or a windmill to start off with, we said, ‘If we can see Mount Washington, and they have the highest wind speeds ever recorded, we’ll go with wind first.’ “

Armstrong plans to open his home to visitors 10 a.m. to 4 p.m. Oct. 1 as part of the Northeast Sustainable Energy Association’s annual Green Buildings Open House.

Michelle Rose, spokeswoman for the association, said the event is a way for people to visit buildings that use renewable energy technologies and other “green” features.

She said last year more than 10,000 people toured some 500 sites, from Maine to Pennsylvania. People can search for participating homes in Maine at http://nesea.org/greenbuildings/.

“One thing very different this year, opposed to years in the past, is we’re getting a bigger range of the type of building involved,” Rose said. “We mostly had single-home residences with a few panels, and this year we’re having lots of schools and multifamily homes and deep energy retrofits, which basically is a full overhaul of the existing building.

“Last year, we had two or three schools in the 10-state region we cover, and this year we have 25 to 30 participating.”

Armstrong said making his home more efficient is an ongoing project.

Over the years, he said, he has added more energy-efficient features to keep up with his family’s power demands.

“It’s designed for passive solar,” he said. “I try to get as much heat from the sun as I can. The house is aimed at the south, I have large-pane windows and it’s superinsulated, 91/2-inch walls.

“I try to keep as small a carbon footprint as possible.”

Jennifer Marrapese, executive director of sustainable energy association, said the goal of the open house is to let people see, firsthand, energy efficiency and renewable energy improvements in their communities.

The goal is to motivate them to adopt similar solutions for their own homes, she said.

“Nothing breeds success like success,” Marrapese said. “When people see for themselves how families and businesses in their own communities are saving energy and money, sustainable technologies and strategies become much more accessible.”

You can see homes and businesses that feature energy efficiency, renewable energy, and sustainable materials at the organization’s website, www.nesea.org.

The site also provides information on ways to reduce a site’s eco-footprint, reduce embedded energy, conserve water and ensure that buildings are healthy environments.

“I think it’s a great way for people to get ideas,” Armstrong said of the open house. “And I think it’s great they’re finally pushing this whole idea.”

The Green Building Open House operates in conjunction with the American Solar Energy Society’s National Solar Tour to help kick off National Energy Awareness Month in October.

Mechele Cooper — 621-5663

[email protected]