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Solar Power: The Answers to Frequently Asked Questions

Get the answers to frequently asked questions on solar power, and find out more about the solar products available.

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answers to questions about solar power

What is a residential solar electric system?

We offer comprehensive, code-compliant systems that allow you to generate your own electricity at home. Designed to interconnect with your existing utility service, they feature solar modules, plug-and-play wiring, power electronics and our patented mounting kits. Our installer network provides system installation and service.

How does a residential solar electric system work?

Solar cells in the modules mounted on your roof convert sunlight directly into DC power. A component called an inverter converts this DC power into AC power that can be used in your home. The system is interconnected with your utility. During the day, if your solar system produces more electricity than your home is using, your utility may allow net metering or the crediting of your utility account for the excess power generated being returned to the grid. Your utility would provide power as usual at night and during the day when your electricity demand exceeds that produced by your solar system. Systems are also available with a battery backup. Part of the power produced by your solar system during the day is used to charge the batteries, which provide power for your critical loads in the event of a power outage.

Will my system work at night?

No. Sunlight must be present for your solar modules to produce power. At night, you draw power from your utility.

Will my system work on cloudy days?

Yes, though they produce less electricity. Under a light overcast sky, panels might produce about half as much as under full sun.

What happens during a power outage?

We offer two types of solar residential systems. One type of system powers your home during daylight hours but does not provide power in an outage, even on a sunny day. Another type of system powers your home during daylight hours but also has a battery backup designed to provide power to your home's critical loads during an outage, day or night.

Does your solar system make hot water?

No. People often confuse our products with solar thermal panels that involve water circulating through tubes to be heated by the sun for swimming pool water heating. Our solar modules convert sunlight into electric current to operate appliances, motors, pumps and other devices.

How can I tell a water-heating panel from a solar electric module?

Solar electric modules are typically one to two inches (2.5 to 5 cm) thick with 32 or more three to four inch (7.5 to 10 cm) blue or black solar cells on the back of the cover glass. Solar water heating panels are generally much thicker and may have tubes connected to a flat black plate under the glass, or a black tank inside the collector panel.

Can I generate heat for my home with a residential solar electric system?

No. Our solar power systems are designed to provide electricity to run your lights, appliances and other electric devices in your home. Other solar technologies are designed to turn the sun's light into heat instead of electricity.

What do the terms on-grid, grid-connected, grid-tied and off-grid mean?

On-grid, grid-connected or grid-tied means connected to the utility electrical grid. Our solar electric systems are designed as on-grid systems, meaning that they interconnect with your existing utility service. Off-grid refers to systems that are not connected to the utility electrical grid. Our solar electric packaged systems are not designed for off-grid applications. An off-grid system must be custom designed by a solar power expert.

How do I know if a residential solar electric system would work on my home?

Solar electric power works for most homes. Our systems are engineered to work with most roofing materials, in most locations where direct sunlight is available, in almost every region of the United States. You need a sunny place on your roof about 120 square feet or 11 square meters (10 by 12 feet or 3 by 3.67 meters) for our smaller systems, and up to 1,000 square feet (93 square meters) for our largest systems. Shading from trees or other obstructions can reduce the practicality of a specific installation. A south-facing roof area is optimal, but solar electric panels can be mounted on west- or east- facing roofs and still produce better than 90 percent of the power of a true south roof mounting.

Why does it require at least 120 square feet (11 square meters) of roof space?

Each solar module is approximately 5 feet (1.5 meters) long and 2-1/2 feet (0.75 meters) wide. The modules are always grouped in a set of four, and the minimum number of modules for our smallest system is twelve modules. This requires an area of at least 120 square feet (11 square meters).

Why is shade a problem?

Because of the wiring design of a solar module, all of the individual solar cells on a module must receive full sunlight for the module to work properly. If any portion of the module is shaded, the entire module power output-even those sections still exposed to sunlight-is lowered.

What if I need a new roof or am building a new house?

This is the ideal situation for installing solar. Before laying the roof, you can install flashable mounting brackets that provide the highest level of protection from leakage.

Can I add reflectors or mirrors around the solar panels to increase the power they generate?

No. Our solar panels designed for use in direct sunlight only.

How many solar panels do I need to produce enough electricity to run my house?

The array size you need depends on your average electrical usage, climate, roof angle, shading problems and many other factors. To approximate the array size you need, multiply your average daily electrical demand in kilowatt-hours by 0.25. The result is the approximate size of solar array, in kilowatts, needed to meet your electrical demand.

Will a system produce enough energy to cover all my electricity needs?

It is important to understand that a solar electric system does not need to provide all of the electricity you need to be of great value. A small system that displaces an average of one-quarter to one-half of your average demand reduces your electric bill. With battery backup, it can deliver uninterrupted power to critical loads during utility outages for days or weeks. We are happy to provide you with a system that supplies 100 percent of your energy needs, but cutting your electricity by 40 to 50 percent is typically the most cost-efficient approach for home solar power.

What other options do I have if the system cannot be mounted on my roof?

If a roof-mounted system proves impractical, a ground-mount, trellis or pergola application may be an option.

If I rent a home or apartment, can I still get a system?

No. Solar electric systems are available only to property owners. The installation of a solar electric system involves the property owner entering a contractual agreement that includes a potential property lien (called a mechanic's lien).

What is net metering?

Net metering measures the difference between the electricity you buy from your utility and the electricity you produce with your solar energy system. Under net metering, any excess electricity produced by your solar energy system is delivered back into the utility grid, effectively spinning your meter backwards. Your meter spins forward when your solar energy system is not producing all of the electricity you are currently using. Your electric meter keeps track of this net difference as you generate electricity and take electricity from the utility grid.

Do all states require utilities to offer net metering?

Many, but not all, states require utilities to offer net metering, but the size and technology requirements vary. If your state does not provide for net metering, you can still use the electricity in your house and enjoy the benefits of clean reliable power from the sun. However, you must purchase a second meter to measure the amount of electricity your system produces and make special arrangements with the utility to receive credit for excess electricity produced by your solar electric system.

Are government incentives available to reduce the price?

Yes. State agencies and municipal utilities offer rebate and incentive programs for homeowners and small businesses to promote the installation of renewable energy equipment such as ours. Incentives can cut the cost of your system in half, saving you thousands of dollars. Your dealer can tell you more about the incentives available in your area.

How much power will a residential system produce?

The amount of power produced by a system varies depending on the size of the system, your geographic location and climate and whether the system has a battery backup.

Can the modules withstand high winds and hail?

The panels are supported by our roofer-designed mounting system that has been tested to withstand 125 mph (200 kph) winds and can work on almost every type of roofing material. Our modules can withstand one-inch (2.5 cm) hailstones at 50 mph (80.5 kph).

How long will my solar power system last?

With no moving parts and made of very inert materials, our solar modules are tough. Most of the related system components should also last for many years without problems. The batteries in our residential system may need replacement in five to 10 years.

How can I tell how my system is performing?

We provide a power meter with the system. Located in your home, your power meter tells you exactly how much electricity you generate and use, and when you send power back to the utility grid. You will be able to manage your household usage like never before.

What maintenance does the system require?

You should go years without problems. The batteries in our residential system may need replacement every five to 10 years. We recommend that the installer do a system check once a year, just to make sure everything is performing, as it should. If it is convenient, you can hose off the modules two or three times a year.

Do I have to buy a service contract?

No. We do not offer an annual service contract. Your dealer may offer a service contract for regularly scheduled checks of the system output and wiring.

How much does the maintenance cost?

Since the maintenance required is very low, your cost should be minimal. Most of the related system components should last for many years without problems. The batteries in the residential system may need replacement every five to 10 years.

Do I need a building permit?

Yes. Your dealer and installer know how to obtain the necessary permits from your local government.

Do I need permission from the local utility to connect my solar system to the grid?

Yes. The local utility has rules and procedures that must be followed to connect any generator to the grid safely and legally. These rules are generally based on national standards with which our systems comply. Your dealer will help you with the documentation and procedures.

Do I need approval from my homeowners' association?

Some homeowners' associations have rules regarding the installation of anything on your roof or grounds. If you belong to a homeowners' association, consult your covenants for details. Many states prohibit homeowners' associations from restricting solar devices.

Can I have a solar electric system on my house and still be connected to city power?

Yes. In fact, our systems are designed as on-grid systems, meaning they are designed to interconnect with utility power.

Can I be totally independent from the utility?

Our solar electric systems are designed to interconnect with existing utility service. Off-grid systems must be custom designed by a solar power expert.

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