When Vivian Van Story moved into one of 23 houses in a new development in North Philadelphia, in a neighborhood long known as Cabot, she wanted to try something novel:

A sustainable home that would help her family save money.

She and her then-husband bought their home in 1983, when architect Robert Thomas, who is known for designing sustainable buildings, had just finished laying out the rowhouse sites.

"I knew we wanted to live here, and that it was somewhere special," Van Story recalls. "We were walking through mounds of dirt, trying to find where our house would be located, but it felt good."

The couple, who lived on nearby Master Street at the time, chose a corner lot measuring 1,920 square feet. (The development totals 1.06 acres.) They took advantage of an opportunity for first-time buyers: to purchase the house for $38,000 with the provision that they live there for five years without selling it.

"We loved the neighborhood, where I had lived all my life, and also liked the idea of owning a house that was built to be easy to maintain with low utility bills," she says.

Thirty-three years later, Van Story's corner house is surrounded with green grass and spring flowers - on a recent afternoon, a colorful awning stretched across the porch at the front of her home. Most of her neighbors also moved into their houses in the 1980s.

Van Story says she is so proud of her home that she helped organize her neighbors and is now chair of the community organization.

"We applied and got permission to name the community Green Hills, which was the original name in the 1800s, and not Cabot, as it had been named in recent years," she says.

Walk into her home and it appears to be much larger than its 1,200 square feet might imply.

The living room features a small wood-burning stove in a brick-walled corner that offers warmth both literally and figuratively. Van Story decorated the space with gently used pieces, including a leather sofa. (She says she finds it hard to believe that people buy so much when others are throwing perfectly good furnishings away.)

The kitchen has an island at which a cook at work can also chat with guests. Polished oak floors can be found throughout the house.

Robert Thomas of CT&C Architects, Philadelphia, is notably proud of his achievement in designing Green Hills, which was one of the first sustainable-energy developments in the city.

"Well," he says, guiding visitors to the sustainable features of the Van Story house, "we can't say it is the first; William Penn planned the city to be sustainable. He was very much ahead of his time, and he planned his grid with energy and sunlight in mind."

Thomas says he planned this development, 23 houses in two rows, so it would receive strong sunlight through the front or the back windows.

On the second floor, he points out that the middle of the three bedrooms does not have a traditional window, but rather a "calculated overhang" that in summer blocks the heat and in winter blocks the cold. It lets in more light than a traditional window would, he says.

Thomas notes that the interior bedroom's windows are set in frames that stick up above the roofline and let in additional light.

Houses in the development have solid walls with vents that can be opened during the day and closed at night. To supplement heat produced by solar panels, there is a backup electric system.

"We planned the porches so there would be a chance for residents to catch the evening breeze in the summer and still have a certain amount of privacy," Thomas says.

In fact, Van Story says, one of her pleasures is sitting on the front porch when it's warm out, shielded from sun by her awning.

"I don't need air-conditioning and don't turn the heat on very much.

"I am very happy here, and the sustainable plans work," she says. "My electric bill is about $28 a month, and that means it works for me."