What do the terms Photovoltaic and PV mean?
Solar electric systems are commonly referred to as photovoltaic systems, “PV” for short. The photovoltaic effect (etymology: “photo” from the Greek meaning light; “voltaic” meaning voltage or electric current) is the ability of some materials (such as PV cells) to convert light energy from the sun into electricity. The PV cells are made up slices of silicon placed under a thin slice of glass. As photons from sunlight beat down onto the PV cells, they excite electrons in the silicon. Small wires on the silicon catch these electrons, and when joined together in a circuit an electric current is created.
What are solar cells made from?
Individual solar cells are made of silicon wafers. Groups of solar cells are made into photovoltaic (PV) modules, commonly referred to as panels.
How does a grid-tied solar system work?
When the sun’s rays shine on a PV array, DC current flows to the system’s inverter, which converts that current into AC. Whatever loads (lights, television, HVAC, refrigerator, etc.) are being used in the home or business use some of that power to perform their jobs. If there is more power being produced by the PV system than what is demanded at a particular time, the excess flows through the meter (spinning it backward) and back to the utility. An example might be in the afternoon, when the sun is shining at its strongest onto the array but no one is home to demand much power. Conversely, power flows from the utility to the home at night when residents return from work and use lots of lights and other loads… and the sun is no longer powering the array.
What is net metering?
Net metering is a special billing arrangement for utility customers who generate renewable energy such as solar power. Net metering allows customers to get credit for the full retail value of the electricity their solar electric system generates. Under this agreement, the customer’s electric meter tracks the surplus electricity generated by the solar electric system and the electricity that the customer consumes. The customer only has to pay for the net amount of electricity they use. In other words, a net metered customer pays for the electricity supplied by their utility in excess of the amount generated by their solar system. Massachusetts investor-owned utilities have net metering standards in place today.
What is an inverter and why do I need one?
The inverter is the brains of a PV system, converting the DC (direct current) generated by the modules in a solar array into usable AC (alternating current). AC electric current is what the lights, appliances, and other loads in our homes and businesses operate on. AC is supplied by the electric utility, and can be “sold back” to the utility! In addition to re-shaping DC into AC, most inverters are capable of tracking instantaneous and cumulative energy production of your PV system.
Would my home or business be a good candidate for solar?
There are many factors to consider, but the most important are the orientation of your potential solar array, shading from trees and other obstructions, and the size and condition of the roof. Southern access is optimal for annual solar PV system performance, but solar panels can be mounted on East and West-facing roofs. Shade can dramatically reduce the performance of your array. The best way to figure out if you’re a good candidate is to contact Brightstar Solar today for a free evaluation.
How do I figure out how big my solar array should be?
One of our solar installers will do a site evaluation where we analyze your electricity bill, the available unshaded space on your roof, and what your budget is to determine the best size for your solar system. Even the smallest system will reduce your energy consumption from your utility! Brightstar Solar does not design systems that are too big for your budget or your energy needs.
Is it difficult to switch to solar power?
No. Brightstar Solar makes it easy to make the switch to solar. Our solar installers will get your solar system up quickly and smoothly so that you can start saving money and producing clean, sustainable energy. You won’t have to make any changes inside your home or business and we pride ourselves on providing a professional, seamless integration of PV technology.
How long do PV systems last?
A solar electric system that is well-designed and maintained has an expected lifetime of 25 years or more. Most PV modules come with a 25-year warranty from their manufacturer, but have been known to last longer than 30 years. Most system problems are a result of poor design and/or shoddy workmanship, which Brightstar does not tolerate. Inverters do need to be replaced every 10-15 years and can fail more quickly if they are in direct sunlight.
What is the warranty on the system?
Most solar modules have a 25-year manufacturer’s warranty and most inverters have a 10 year warranty, with the exception of microinveters which often have a 15 year warranty. Brightstar Solar provides a 10-year workmanship warranty on the installation.
Do solar panels wear out or lose their efficiency quickly?
No, studies suggest that solar panels lose about a .25% efficiency per year. Most panels come with a 20-25 year warranty and are said to last twice as long.
How long does a typical solar installation take?
The length of a solar installation depends on the size of your PV system and its complexity. The on-site installation time for most residential jobs ranges from a couple of days to a week or two. Brightstar Solar is a full-service Massachusetts installer and we will include an estimated project timeline during the contracting process.
Will Brightstar Solar manage the building permit process for the solar system?
Yes, our solar installers will handle the entire permitting process and will ensure the appropriate electrical, building, and utility inspections are passed successfully.
Will my roof need repairs after a solar system is installed?
It’s best if your roof is in good condition prior to having solar panels installed. Once they are installed, the solar panels will actually protect your roof from the elements like weather and sun and provide some level of insulation.
Is solar viable in Massachusetts?
Absolutely! Our available sun power here in Massachusetts is about 80% of the sunniest parts of the Southwestern US and is much greater than anywhere in Germany, one of the leading solar countries in the world. (Germany is about as sunny as Alaska!)
Well, if we’re only getting 80% of the sun in Massachusetts, how can it be viable?
Economic viability is a function of the available sun power and local incentives. Some states with a tremendous amount of sunny days do not incentivize their citizens financially. Massachusetts is among the 5 most “solar-friendly” states in terms of economic incentives in the form of rebates, tax credits, and net metering policies.
What about the cold?
Colder operating temperatures are actually better for PV! Although it may intuitively seem that the Arizona desert is ideal for PV, the intense heat decreases the efficiency of the modules. Cooler temperatures mean higher efficiency.
Will I still generate electricity on a cloudy day?
The electricity production will not be as high as on a sunny day, but your system will still generate electricity because there will still be some irradiance. Under a light overcast day, panels might produce about half as much as under full sun.
What happens with my solar array when it snows?
When it snows, the snow may cover the solar panels and affect the production of your system. However, in most cases enough sunlight will still be able to penetrate through to the modules, warming them and melting the layer of snow that is on them. Snow typically clears from your solar panels much sooner than other parts of the roof.
If my power goes out, will my electricity still work because I have solar panels on my roof?
The vast majority of residential PV systems do not have a battery backup system but instead use the utility as a “virtual battery”, dumping excess electric power there at certain times, demanding power from the grid at others. During a power outage, a PV system’s inverter will instantly shut down the system so that the array (which is producing power whenever even the slightest amount of light shines on it) cannot backfeed power into the grid. (This would be very dangerous for the utility linemen working on a downed power line near your house.)
What should I do if my solar panels are damaged in a storm?
If you have purchased a solar electric system that is installed on your residence and you already have homeowners’ insurance, your insurance company should insure the panels against damage.
How good are the incentives right now? Do you think the incentives will get better with time?
Depending on where you live and other factors, incentives may cover up to 50% of the cost of your solar system. Incentives are not likely to get better in the future. These incentives and rebate programs are funded by the state and Federal governments and are constantly under budgetary scrutiny. In other words, they may not be around forever. The purpose of these incentive initiatives is to spur deployment of renewable power. As more and more systems are installed, incentives and the state-sponsored loan program will phase out. The time to act is now.
If I purchase solar next year, won’t it be cheaper and won’t the technology be better?
No, right now is the best time to invest in a solar system taking into account the combination of technology and cost. While solar panel prices have been decreasing slightly, demand has been increasing. As adoption increases, the incentives are being reduced. These programs are only in place to subsidize the cost of solar until the price of components goes down. (At the same time, the solar manufacturing industry is working to make less expensive products so these subsidies will no longer needed.) Brightstar Solar will continue to evaluate innovations in technology and will offer best-of-breed technologies to our customers when we feel they are reliable and cost-effective.
What is the average increase in the electricity price annually?
In the past year, Massachuestts residents are seeing electricity rate hikes close to 17%. An investment in solar will protect you from these increases in electricity.
When I sell my house, how will solar affect my home value?
Solar will increase the value of your home. Studies show that home value increases by $20,000 for every $1,000 you cut from your annual electric bill ($83/month). This is because the cost to operate your home will be reduced as long as your system is functioning under the sun.
What kind of maintenance is required for the installed solar panels?
Because there are no moving parts, almost no maintenance required. The panels just have to be kept clean and rain can do that most of the time. If you aren’t getting much rain or the panels are soiled from bird droppings, you can hose them off. (Do not hose them when it’s hot, because theoretically the glass could break because of thermal shock. We recommend that you spray the panels in the mornings or after the sun sets and the panels have cooled.)
How do I know if my solar electric system is producing what it should?
Most inverters have an LCD display that can easily tell you the system’s actual production. Our team can also install a web-based tool that can monitor your system real-time. Our proposal and contract documents include a report with the projected production for your system – you can compare it to what the system has been producing to see if there is any gap.