Your electric meter spins proportionally to the amount of power you’re using. Now imagine it slows to a stop – then starts spinning backwards. All of a sudden, you’re in the utility business.

This is what happens when a solar energy system produces more power than what is currently used in your home.  

More and more Three Villagers, including myself, are experiencing this personally. Many take advantage of the Long Island Power Authority's Solar Pioneer Program, which offers rebates to individuals who install solar energy systems in their home.  According to LIPA, the total number of solar energy systems installed on Long Island through the program increased by 73 percent from 2009 to 2010. In an email to Patch, LIPA said only three homeowners in the Three Village area installed solar systems in 2009, but that number swelled to 21 for 2010 – a seven-fold increase in the number of solar energy installations during that same period.

The amount you receive from the Solar Pioneer Program depends on the size of the system you install and the current rebate rate. In an email to Patch, LIPA said the program has distributed nearly $95 million in rebates since its inception in 2000, with more than one third of this amount given during 2010. Combined with substantial federal and state incentives, these systems are not just for the ultra-green and geek chic.

Solar energy systems are only one part of the growing renewable energy market.  According to the Department of Energy’s Energy Savers website, renewable energy “is derived from sources that are regenerative or for all practical purposes can not be depleted.” Some of these energy resources include wind, moving water, geothermal heat, and sunlight. Three Village even has its own energy technology research engine – the AERTC at Stony Brook University – exploring those areas. Renewable energy has many benefits, chief among them a lighter impact on our environment and reduced dependence on foreign oil.

Not to mention it can eliminate your electric bill.

Ed Hayes of Setauket got an earlier start than many of us when his solar energy system was installed several years ago.

“I went nearly two years without paying an electric bill,” which has saved him around $300 per month, he said.

Solar power can have its pitfalls. Aesthetically, some feel it can disrupt the look of a neighborhood, leading to resolutions like a recent Poquott village moratorium on certain types of renewable energy devices. Weather is another factor: this past winter’s heavy, lingering snow blocked the sun's exposure to the solar panels at the Hayes residence, which reduced his system’s output by about a month’s worth of power. Now the snow has melted, and his system is back to full production.

“The installation of solar panels has also reduced my attic temperature by 15 degrees,” Hayes said. This is due to the shading provided by the panels, which translates into lower cooling costs for his home during the summer.

So how does solar power work, anyway?

“The two main components of a typical grid-tied solar energy system are the photovoltaic panels and the inverter,” explained Joe Milillo of Long Island Power Solutions.

The photovoltaic (PV) panels are the most obvious because they sit on your roof.  They basically collect sunlight and turn it into electricity. The inverter then converts the power from the panels into the standard 110 Volt, 60 Hertz, AC power that most of us are familiar with in our homes.

The inverter is also charged (pun intended) with the task of synchronizing its output with LIPA so that any extra power it produces is usable by other homes in your area. ‘Grid-tied’ means that your home remains connected to the electric utility’s grid and can be powered by both the utility and/or your own solar energy system.

Despite the LIPA incentives, government rebates and dropping system costs, there are still a few things to consider before purchasing a solar energy system. First, you need to make sure that your home has ample direct sun exposure. If not, you may not generate enough power to cover the installation costs. You'll also want to make sure your roof is in good condition, because replacing it after the panels are installed can be costly.

Also, make sure your system is sized correctly for your home. While producing more than you use may get you a check back from LIPA, the utility only pays a wholesale rate, which is a fraction of what you would pay them. Finally, if LIPA experiences a blackout, your system will not produce any power – even in the middle of a sunny day. A special meter is put in place to prevent power production when no power is present on the grid as a safety measure to keep your system from energizing the grid while workers are repairing the lines. LIPA's Solar Pioneer FAQ web page can answer some of the most common questions.

The easiest way to figure how much a system will cost and how much energy you’ll be able to generate is to have a contractor come to your home and give you an estimate (typically for free). They have modeling tools which allow them to estimate your output in dollars and cents, and they will also be able to file the LIPA Solar Pioneer application for you.

Just for reference, my own out-of-pocket cost was only about 20 percent of the total system cost, and I’ve estimated it will take about seven years to pay for itself.