People are doing double-takes and slowing down to take a look at what’s in the yard of the Simmonsville Avenue home owned by Kim Calcagno and Christopher Martin.

The couple, in an effort to save money on their electric bills and also use “green technology,” has had solar panels installed in their yard by Alteris Renewables, which sprung from the merger of two separate companies: Solar Works and Solar Wrights.

According to its Web site, Alteris Renewables, the largest company of its kind in the northeast, has completed more than 2,000 residential and commercial renewable energy installations in the states it serves. Solar Works was founded in 1980 and Solar Wrights started in 2000; they merged last December.

Calcagno’s is the only home she knows of in the town that has had this kind of photovoltaic solar installation.

“When the guys were installing it, people kept stopping by to ask what they were doing and how much it cost,” she recalled. “I was amazed how fast it went up – in one day – and the electrician, their own guy, came the next day. They do everything for you – they pull the permits, they deal with the town – they arrange for inspections. You literally just make appointments for them to come.”

When the house uses electricity, they get a bill from National Grid; when electricity is collected, the amount is credited to their account.

“National Grid took the electric meter off the house and installed a ‘net meter’ that goes forward and backward,” explained Calcagno.

Both Calgagno, who is refuge manager at the Audubon Society of Rhode Island’s Powder Mill Ledges in Smithfield, and Martin, employed by Harvard Pilgrim Health and co-founder of the online Quahog.org site, work for nonprofits, so cost was an issue. Knowing that tax incentives would help after the installation, the couple sought to keep the installation costs down by doing some of the work themselves.

Calcagno had a friend who owns a backhoe and, knowing how rocky her property was, she knew she would need heavy equipment to dig the necessary trench and to remove any giant boulders they might find underground. A trench was necessary to bury the power lines from the solar panels to the house.

Calcagno and Martin also had access to an auger to dig holes for the upright structures and poured the concrete themselves. “That saved us at least $3,000,” said Calcagno. “Doing it ourselves actually saved us a lot of money.”

The total cost of the installation, before incentives, was a little over $15,000.

She had considered having an array of panels installed on her roof, but the roof was too old and at the wrong angle to the sun. Instead, she had them installed in her 2½-acre yard, which is bordered by Simmonsville Brook and is free from shade year-round. At least 200 square feet of land is recommended, and the array must get four to six hours of direct sun each day.

The optimal solar energy system is installed on a completely un-shaded roof that faces due south. The system will perform best if it's oriented approximately at a 10- to 40-degree tilt angle.

Calcagno’s 16 panels are “rack-mounted” and can be set to different angles to the sun, depending on the season. They come with a 20-year warranty, and need very little maintenance. Black in color, they absorb the light from the sun.

“I was a little worried … but it’s getting where there’s enough in the state – the renewables are becoming more commonplace – that they know what they’re doing,” she said. “We don’t mind the look of it – it’s actually been attracting a lot of attention.”

Before any work was done, Alteris sent a representative out to take a meter reading in the yard (to see how much sun it gets) and look at the household electric bill.

“It won’t generate all our electricity,” Calcagno said. “We couldn’t afford a bigger system – a 4 kW system would have been needed – but it will supply about one-half to two-thirds.”

On Monday, Feb. 2, under bright sunlight, the meter registered 1,800 volts coming from the photovoltaic panels.

“Earlier it was producing more than 2,100 – on a cloudy day it produces a lot less, and if it has the slightest shadow on it, it loses some collection power,” Calcagno said.

An inspector recently pointed out that, although the recent snow had melted from the panels, some of the snow had gathered, covering the bottom of the panels and blocking them partially. Calcagno shoveled the snow, and regained about 20 percent in efficiency.

It will be possible to add on to the existing array in the future, increasing the amount of power generated.

“The one at the Audubon is 20 kW,” she said – that was how she first became familiar with the industry.

Calcagno praised Alteris Renewables and their earth-friendly energy technology. At Audubon, she has hosted many speakers and classes on a variety of “green” topics and is a fan of new earth-friendly technologies.

“We had wanted to do this for a while,” she said. “[And Alteris is] such a breeze to work with – they really have their finger on the pulse of what’s going on.”

The state has tax incentives called “incentive buy-downs” and a pool of money it uses to fund the program. Calcagno said the state pays about $3 a watt “if you qualify.” She will qualify also for a $2,000 deduction on her federal tax return and $3,500 on her state tax return, plus an incentive of $8,600 that was deducted from the total price of the installation.

“That’s the only way we could have afforded it,” she said.

The household’s first electric bill since the installation didn’t show much savings, probably due to the extreme cold during the last month, but they anticipate savings in future bills.

“In the summer, I think we’ll see a huge difference,” Calcagno said.

People frequently ask Calcagno about her array – usually the same questions.

“We are still connected to the Grid, and get a bill every month,” she said (although theoretically, she could receive invoices listing a credit in the future). “I’m still getting used to the bills – it’s way more complicated than the regular bill.”

In the event of a power outage, the system has an automatic shutoff, mostly to protect any line workers.

The array produces 220 DC current, which is converted to 110 AC current by an inverter mounted on the inside of the basement wall as part of the installation. With the change in administration, Calcagno still isn’t sure if she would have saved more by waiting for Barack Obama to take office (the installation was completed in November and connected in December), but decided to move forward when she found out her incentive would be granted before the end of 2008. Calcagno and Martin are also looking to expand their solar power usage – Calcagno said her “real goal” is to put in a solar hot water system that will power radiant heat in the house.

“The novelty hasn’t worn off yet,” she said.

Wondering if your home or business might be a good candidate for solar power? For more information, visit www.alterisinc.com.