Solar Energy Frequently Asked Questions
Below we have developed a list of frequently asked questions about solar installations to help guide you in making the most accurate decision for your renewable energy needs.
Is utility-scale energy storage available?
AGT partners with a number of utility-scale energy storage system providers. Systems that AGT has access to include ice, molten salt, oil, water, battery, flywheel, and hydrogen storage. The technology for these systems is improving, however, they are currently cost effective only in niche situations.
Do I need special insurance?
You will need to expand the insurance coverage on your facility to include the value of the PV system. Many insurance companies are now familiar with PV systems. In addition, AGT can help you acquire business interruption insurance and in some cases insurance on sunlight or system performance.
How can I tell how my system is performing?
Every building contains a power meter tells you exactly how much electricity you generate and use, and when you are sending power back to the utility grid. If a grid tied system produces more power than the appliances in the building are using then the meter will spin backward. AGT also offers a system monitoring device and service with every installation. A data monitoring card is installed in the inverter providing a real-time, web-based feed of system production. This data card allows for detailed monitoring with better than +/- 5% accuracy. The monitor card detects system interruption and data glitches while feeding instant email alerts to programmers, allowing them to maintain constant vigilance of installations and immediately dispatch an alert. System data/performance can be accessed through a high-speed internet connection and provides you with current weather conditions, AC output, lifetime kilowatt hours, system offsets/efficiency, and daily kilowatt hours produced. The AGT solar monitoring system also shows environmental offsets as a result of the system in tangible terms such as CO2 offset, trees saved, and waste recycled rather than land-filled. To see a live solar monitor system, visit www.AGTSolarDemo.com.
How do solar modules work?
Solar panels are mostly silicon-based, a material that is a great absorber of light and energy. The solar light excites the valance electrons in the silicon allowing them to ‘flow’ and Direct Current (DC) voltage is created. However, most buildings use Alternating Current (AC) voltage to power their various systems and appliances. An inverter is necessary to convert the DC to AC voltage. Depending on local utility requirements, the power from the inverter is fed back into your electrical Main Distribution Panel (MDP). From here, your solar power acts just like conventional utility power. It provides the power to meet your current demands. Anytime your PV is not able to provide 100% of the power to meet your demands, additional power is drawn from the utility as normal. Anytime your PV system provides power in excess of your demands, the excess power flows back through the utility power meter and is stored in the grid until needed.
What is the difference between crystalline and thin film PV panels?
Crystalline Silicon (c-Si)cells are wafer thin slices of silicon crystals. There are two types: monocrystalline silicon cells are cut from a single uniform crystal and multi-crystalline/Polycrystalline Silicon are cut from multifaceted crystals. There are three main types of thin film technologies commercially available today: Amorphous Silicon (a-Si), Cadmium Telluride (CdTe), and Copper, Indium, Gallium, Serenade (CIGS). The technologies listed in order of power density are monocrystalline, polycrystalline, and thin film. Crystalline modules are more expensive to manufacture and require rigid framing to support their fragility, while thin film modules consume far fewer resources and can be applied to a variety (including flexible) surfaces.
If I sell my property, will my solar installation have an effect on the sale price?
Energy conservation and renewable generation add value to a property. Solar energy can be one of the best improvement investments you make. The top selling point of raising resells value is that the new owners will inherit a building retrofitted to reduce overhead costs on heating, cooling, and appliances. Make sure to emphasize the value that a solar installation brings and market this in the list of extras. According to the Appraisal Journal in the October 1998 article, “Evidence of Rational Market Valuations for Home Energy Efficiency,” a home’s value is increased by $20,000 for every $1,000 reduction in annual operating costs from energy efficiency (Nevin, Rick).
Is a building permit required to install a solar energy system?
Yes, you will need to obtain building permits to install. Roofing, electrical, and plumbing (if including a solar thermal system) codes also apply. Solar contractors include the price for permits into their cost estimate.
Is shade a problem?
While shade is a problem, it doesn’t mean that solar is not a good option for you. Through efficient site design, equipment selection, and proper modeling MOST site shading issues can be overcome.
My region is prone to high winds, such as hurricanes. Is PV safe for my area?
Yes. Advanced Green Technologies can help you determine which type of system is best for your high wind zone risks.
My region is prone to hail. Is PV safe for my area?
Yes. Advanced Green Technologies can help you determine which type of PV system is best for your hail zone risks.
What are the components of a PV system?
The typical components of a grid-tied PV system include PV modules, an inverter, associated wiring, a combiner box, safety disconnecting switches, and an interconnecting circuit breaker to tie the PV system to the existing electrical system. The PV module is the basis of the system. The number of PV modules determines the amount of power that will be produced by the system. An array is the arrangement of numerous PV modules. The modules are connected together in series to form groups called strings. String size, the number of modules connected together in series, is used to determine the DC voltage. The combiner box is used to take the paralleled strings and combine them into a single output to send to the inverter. The inverter’s function is converting the DC power, or Direct Current, into usable AC power, or Alternating Current. An inverter’s name plate rating is determined by the amount of power that it is able to output. A 5kW inverter is able to output a maximum of 5,000 W.
What determines the size of a PV system?
Several factors determine the size of a solar energy system. To determine the appropriate solar installation to best match your needs, the following must be considered: how much electricity you use, how much sunshine is available at your location, the size of your roof, how much you are willing to invest, and the government incentives that are available for you to install a solar energy system. The AGT engineers will then personalize a system layout specific to your needs.
What does photovoltaic mean?
The word itself helps to explain how photovoltaic technologies work. The word has two parts: photo, meaning light, and volt, a unit of measurement for electricity. . Thus photovoltaic literally means light-electricity.
What happens during a power outage?
Grid-tied inverters are designed to work only while they detect a clean, stable signal from the existing utility grid. Once grid power drops outside of the inverter’s parameters, the inverter shuts down. If you need a PV system that works during a power outage, AGT can help you with that also.
What happens if snow covers my solar panels?
After a snow storm, when the sun comes out, the solar radiation penetrates the snow and heats up the modules melting the snow from the bottom up. The melting at the surface of the module allows the snow to slide off. Additionally, if the modules are mounted at an angle, gravity will assist.
What is 'Net Metering'?
This means that your utility company will give you the same retail rate for electricity that you “sell back” to the utility. Every utility will have different rules for this, but the basic premise is that they will buy electricity from you at the same rate that you buy electricity from them.
What is a solar tracker?
These are generally deployed on ground-mounted utility-scale farms and are designed to follow the sun’s path during the day and through the different seasons to capture the maximum amount of sun. A tracker increases the annual production of a PV system at the cost of additional system complexity.
What is solar electricity?
Solar electricity is the conversion of sunlight directly into electricity. Solar energy is possible whenever sunlight is available, but more electricity is produced with more intense and direct sunlight.
What is the lifespan of a PV system?
The PV cells themselves will work indefinitely and produce electricity as long as they have contact with sunlight. Manufacturers provide a twenty five year warranties on most products, however system owners report their systems continue production past the determined twenty five year lifespan.
What is the significance of the fact that solar is a renewable energy source?
Unlike traditional power generation sources, PV/solar produces electricity using a clean, renewable source—the sun. It does so without creating noise, emitting pollutants that cause climate change, smog, acid rain, or polluting our water resources. Even when the emissions related to solar cell manufacturing are counted, photovoltaics produce less than 15% of the carbon dioxide from a conventional coal-fired power plant. In fact, using solar electricity to power a million homes would reduce carbon dioxide emissions by 4.3 million tons per year, the equivalent of removing 850,000 cars from the road (Source: Environmental Protection Agency (EPA).
What maintenance does the system require?
Your system should go years, even decades, without problems. We recommend that the installer conduct a system check once a year, just to ensure everything is performing as it should. Otherwise, you can clean the modules two or three times a year with water to rid them of dust and debris. If your system includes batteries, they may need to be replaced every five to ten years.
Will a system produce enough energy to produce all my electricity needs?
It is important to value a solar electric systems contribution to providing you electricity and understanding that a solar installation does not need to cover all your electricity demands to be a great asset. An average residential system installation could reduce your electric bill by up to one-half. A system that supplies all of your energy needs is possible, but typically the most cost-effective installation will cut your electricity by forty to fifty percent.
Will my roof's warranty be affected by a solar installation?
No, as long as you use a certified roofer, your roof’s warranty will be carried over. But be wary of contracting an uncertified/untrained individual to install your solar system. Besides making engineering and electrical mistakes, if a roof leak or issue occurs after installation your roofer may not be liable for warranty or inspection if your roof experienced a faulty solar installation. All AGT authorized roofing contractors are certified to install solar systems as per our training programs.
Will my system work at night?
No. A PV system requires sunlight to produce power. At night, you draw power from your utility.
Will my system work on cloudy days?
Yes, your system will work on cloudy days, but it will produce less electricity. Through an overcast sky, panels produce approximately half as much as under full sun.
If you have any questions we did not answer, please contact us today and we will be happy to help you. We have friendly solar experts standing by ready to help.