Actually, this wasn't a surprise. Chen, who lives in River Forest, had booked a stay at her friend Ginger Vanderveer's family estate on St. Croix, a six-acre resort called Northside Valley. And not surprisingly for an Oak Parker, Vanderveer has made this place a little different.

In fact, she touts her resort as an environmentally friendly way to get away. From the mini-resort's solar-powered front gate to the towels and sheets made from bamboo fiber (a more sustainable crop than cotton that also produces 35 percent more oxygen), she talks readily about the many signs of eco-awareness around the estate.

Vanderveer grew up on St. Croix, and her parents built nine homes on the island-one for themselves and one for each of their eight children. Her father, Phillip Brown, a native Midwesterner and former diver for the U.S. Navy had occasionally been stationed around Puerto Rico.

After he left the Navy, he decided to return to the Caribbean to start a family. When it came time to find a place to live, he took a page from the book of another Oak Parker-Frank Lloyd Wright.

"He liked what Wright had done here with prairie-style houses fitting in with the landscape, so he decided he would do the same kind of thing," Vanderveer said. "Not a prairie style, obviously, but in his case he used a Philippine style to fit in with the Virgin Islands."

And so with the help of his wife-and eventually, his children-Brown set about constructing villas out of the island's native stone. He built them with wide-open rooms, and filled them with screens. He fashioned the walls out of concrete and tiled the floors.

With the help of shade from the many trees, the island breeze keeps the villas cool for visitors today, naturally ventilating the rooms and making air conditioning unnecessary.

"The vegetation absorbs a lot of heat," Vanderveer said. "It's more comfortable there in the summers than in New York or South Carolina."

Chen visited Northside Valley last Easter right at the end of the peak season in St. Croix. With her daughter, two nieces and her sister-in-law in tow, Chen took the dive and decided to rent a villa.

"It was really incredible," Chen said. "I wasn't sure what to expect, and it was really beautiful."

Chen knew Vanderveer through a few close friends, who had worked with her on some environmental projects around Oak Park and River Forest (Vanderveer plants prairie gardens in the area when she's not in the Virgin Islands).

So when Chen booked her stay at Northside, she had an idea her experience would have a Green tint.

"I knew she was calling it an eco-resort," Chen said. "Being at Northside, you don't feel like it's a huge resort that's torn down things just so you can be there-it's not made solely for tourists."

Indeed, Vanderveer and her brother, Phillip, only recently converted the villas to a more environmentally-friendly theme.

"It would have been hard to do this [alone], but my brother came down," Vanderveer said.

There wasn't much to do with regard to the land, she said.

"[It] was kept very natural," she said. "There are still a lot of native trees, plants and beautiful vegetation. The way my father built them, he took advantage of the natural settings."

Aside from the landscaping, every villa is geared to be eco-friendly.

Each house's wastewater drains into a septic tank, which Vanderveer said employs a "soak-away" system, where waste naturally decomposes with the help of microorganisms.

To help the system, Vanderveer offers environmentally-friendly cleaning and bath supplies to guests, which work well with the septic tanks and with nature.

"You don't put bleach into a system like that," she said. Bleach kills bacteria and microorganisms, which can disrupt natural decomposition in the septic tank and cause trouble.

At Vanderveer's own house, the only room that drains to the septic tank is the bathroom-all the rest of the water drains into the grass outside. For example, the high-efficiency washing machine's runoff goes directly outside to a Julie mango tree.

Throughout Northside, Vanderveer uses exclusively energy-efficient compact fluorescent light bulbs, with the exception of a few lights powered by even more efficient LED bulbs.

And there are greener upgrades in the works. She's looking into getting solar water heaters, which will supply the villas with water heated by the sun's rays. Northside's drinking water system may also soon be revamped to be filtered with ultraviolet rays like those emitted from the sun.

These features, of course, come at a price. It's not particularly easy being green, especially on the pocketbook.

"There's at least a 30-percent markup on natural products-maybe even more like 100 percent," she said, such as the bamboo towels or the eco-friendly cleaning products. When combined with shipping costs, it runs her a pretty penny to get the right supplies for her business.

But there's a little secret to her marketing scheme: Her devotion to environmentalism is actually saving her money in the end.

"If I weren't eco, and I was trying to run these houses like a hotel, with air-conditioning, TV, cable, and hot water available at any moment, I could not afford to rent them at any of the rates you see [on the website]," Vanderveer said. "Economically, the only way I can afford to be in business is to be ecological."

Recalling her trip, Chen didn't seem to have any problem at all with the environmentally friendly themes of the resort. The open windows seemed to be one feature of the villas that particularly stuck in her mind.

"The air just flows right through because there's no windowpanes, only screens," Chen said. "You almost feel like you're outside even though you're inside; you feel like you're in the rainforest."

And it seems the eco-themes have stuck with Chen, as well.

"I think it made us realize that we can have an impact-either positive or negative-on the environment," Chen said. "We slowed down, we used less electricity in St. Croix. I think everybody came home with a different sense of making our contribution, making changes."

For more information about Northside Valley, go to www.northsidevalley.com.