solar power 101

What is a Photovoltaic (PV) Panel?

The smallest unit of a Solar Panel, also known as a Photovoltaic (PV) Panel, is called a cell. The main component of a PV Cell is Silicon, which, when combined with other elements, is able to convert solar energy into electricity. PV cells are then arranged in a grid to make a PV Module, which is arrange into a PV panel. For sites that need large amounts of energy, panels are arranged in PV Arrays.

The best way to compare PV Panels from different manufactures is to compare:

● Efficiency: Energy output as compared to energy input. Measured as a percentage this information indicates how much of the sun’s energy that hits the surface of the cell is being convert

● Tier: Levels of efficiency from 1 to 5, 1 being the best rating

● Density (W): Realistic output of energy per area of solar panel. the higher this value, the fewer solar panels needed


Is there enough sun in Virginia?

Many people assume that because Virginia is so far north, we do not get enough sunlight to justify the costs of installing solar panels. In fact, the opposite is true; Virginia receives as much sunlight annually as Florida. “The sun delivers more solar energy to the Earth each hour than the entire human population uses in a year” and “almost every region in North America receives enough sunlight to make home solar worthwhile” (Pure Energies).

Sunlight in America

The Economic Benefits.

Across the nation people have taken advantage of solar energy primarily for is economic benefits. Several studies have shown that installing solar panels on your  property will increase your home’s value. With a standard 5-kilowatt solar system home values increase by 3.5% or an average $19,000 increase for and $500,000 home. Another way to view this concept is that for every $1 you save on electricity, the value of your home increases by $20. On average, solar panels return 2-4 times their cost in save electricity bills and typically pay for themselves completely within 7-15 years. (Pure Energies)

US What you could save

Another way to view how much money you can save by switching to solar is to consider your solar energy production as a percentage of your total electricity bill. Simply put, if solar accounts for 70% of your energy usage you will see at least a 70% reduction in you electricity bill. This remains true no matter how expensive electricity gets, so that as electricity cost go up, so does the value of your solar system and your home. Yet another economic perk of solar panels is the federal tax credits for all residential solar electric systems until December 2016. Any taxpayer can get a 30% rebate on their property taxes. For more information visit this link.

It is very expensive to implement an off the grid solar system.  For this reason, most opt for a grid-tied system that utilizes a process called net-metering. This means that if your solar system produces more electricity than you use, the excess will sent back into the grid winding your meter backwards. Whenever the panels are not producing enough energy (i.e. during the night) your system will pull electricity from the grid, winding your meter forwards again. The end result is that you only pay for electricity that you use in excess of you what your solar panels produce.


The Environmental Benefits.

The environmental benefits of installing solar panels, while more subtle, are just as significant as the economic benefits.  The more people who send excess solar energy to the grid, the less energy that the electric companies will need to produce. This means that every solar energy user is helping to reduce the manufacture of non-renewables. Coal mining, through drilling and mountaintop removal, fracking for natural gas, and oil drilling generate 8-51 times more greenhouse emissions than solar energy (Pure Energies). This does not account for additional environmental damage resulting from habitat destruction, oil spills, and water and air pollution.


What makes your PV Panels efficient?

When looking at the ideal performance and efficiency of your solar panels, there are a number of variables that should be considered. The orientation of your roof, for example, should be south facing in order to maximize the amount of sunlight captured throughout the day, (Pure Energies) and the pitch (tilt) of your roof should also be considered, as the degree of the pitch will affect the amount of sunlight received. Temperature and shading also affect the efficiency of solar energy production. Panels ideally should be installed a few inches above the roof so that the airflow may prevent overheating, and shading should be avoided as much as possible, as it may cause energy production to suffer or even shut down.  (Pure Energies) Because the average solar panel converts 11-15% of sunlight into energy, it is essential to have optimal efficiency in your own panels. (Pure Energies) The higher the efficiency, the fewer solar panels needed to produce the same amount of solar energy.


Additional Resources

LEAP: Get Started with Solar

Solarize Charlottesville

Solarize NOVA