Imagine saving thousands of dollars for being a low energy user and then never paying another electricity bill again.

This is exactly what SunWork Renewable Energy Projects did for Arlene Sheehan and Paul Cole of Palo Alto. Sunwork is a 501(c)(3) nonprofit that benefits the eco-conscious by installing solar electricity systems on homes with a small energy footprint, using the help of trained volunteers.

"It wasn't hard for us to qualify," Arlene Sheehan said of her status as a low energy user. "We have computers, washers, dryers, an oven, dishwasher and a microwave, and we qualified easily."

Sheehan and Cole, a working couple whose children have moved away to college, had considered installing solar panels to power their home in the past. "I am environmentally conscious and wanted to reduce my carbon footprint," said Sheehan. But the expense of the project had deterred them, until they found Sunwork.

"By using volunteers, we're able to put solar in for about 25 to 35 percent less than normal," said Reuben Veek,  executive and operations director at SunWork.

Sheehan and Cole's installation, just last week, cost $13,000 before subsidies, or $4.80 per watt, whereas most companies charge about $6.50 per watt, said Veek.

The homeowners will receive about $3,000 back from the Photovoltaic (PV) Partners Program of the City of Palo Alto, which provides rebates for any extra solar power generation installed in a home. Sheehan and Cole will also receive a federal tax credit in 2011 for 30 percent of the remaining cost of their system, another nearly $3,000.

"We will end up paying $7,400 out of pocket," said Sheehan. "The price was remarkably low compared to estimates we got in the past."

Solar energy has become an increasingly popular energy alternative in recent years. "It's a well-tested technology," Veek said. "I don't see the price of electricity going down, so solar will only look more and more appealing."

But solar panel installations are not always easy. "Palo Alto has a reputation in the Bay Area for being the hardest jurisdiction to get permits," said Veek. "It's a reputation that's exaggerated and a little bit deserved."

Sunwork, which completed its first installation in August 2009, has also installed solar panels in homes in Sunnyvale, Menlo Park and Emerald Hills.

By using flourescent light bulbs and low energy appliances and turning off the lights when they were not using them, Sheehan and Cole used 3,500 kilowatt hours last year. SunWork requires that a two-member household use less than 6,000 kilowatt hours per year to qualify as a low-energy user for installation. "We're fairly average electricity users," said Sheehan.

With their 12 solar panels, each 40 inches wide by 65 inches tall, the couple's home will generate 3,600 kilowatt hours per year. Whatever solar energy the couple does not use will be paid back to them by the city at the end of the year.

"We're thinking this thing will pay for itself in about six years," said Sheehan.

Sheehan and Cole will now have no electricity bills to pay, and any equipment and labor costs associated with the panels will be covered under Sunwork's 10-year warranty. The solar panels will probably last up to 25 or 30 years, Veek said. Production decreases by about one percent per year, but he said the panels should retain 80 percent of their original power at the end of the 25 years.

Once the panels are installed, users should consider a future fee of about $1,500 to $2,000 to replace the inverter, which converts the energy so that it can be used in a home. "You will usually go through two [inverters] in a lifetime of the system," said Veek. If sections of the roof are shaded at certain parts of the day, multiple micro inverters may be necessary so that one is always in the sun.

Veek, who supervises four or so volunteers to do each installation, described the volunteers as "environmentaly-minded folks who are looking for something to squeeze into a weekend to help out."

Though Sheehan and Cole's friends asked if they were worried about volunteers doing the installation, Veek was in charge of the technical work while volunteers simply helped out. "They're learning by watching," Sheehan said of the volunteers. "It's a great service, because he's training these people."

There are two ways to qualify as a low energy user for solar panel installation by Sunwork. "If you use a number of kilowatt hours per year on threshold, then you qualify automatically," said Veek, referring to the Housheld Annual Electricity Use table on Sunwork's website. "Otherwise, we can consider that you've taken the steps available to reduce your usage. It's case by case."