What is a solar cell and a solar module?
A solar cell, also called a photovoltaic (PV) cell, is the smallest element that converts light into electrical energy. Each cell is made of silicon, like a computer chip. The silicon is treated so that it generates a flow of electricity when light shines on it. Solar modules are series of solar cells wired together.

What exactly is a solar electric power system?
A Solar Energy System consists of solar electric modules in lightweight panels, enclosed wires, an inverter to convert from D.C. to A.C. (house current) and sometimes an optional battery backup pack. The solar panels are typically installed on an un-shaded rooftop, facing the southern sun. Systems can be installed on the ground as well if your roof is not well-suited for a solar power system. The inverters and other equipment are generally small and can be installed inside your basement or garage or on the outside of your home.

What are the different types of solar technologies?
The four types of solar technologies are:

• Photovoltaics: Photovoltaic solar cells, which directly convert sunlight into electricity, are made of semiconductor materials. This can include very simple cells that power calculators and watches and complex systems that can light houses.
• Passive solar heating: Buildings designed for passive solar and daylighting combine building materials that absorb and slowly release the sun’s heat with design features such as large south-facing windows. No mechanical means are employed.
• Concentrating solar power: This technology uses reflective materials such as mirrors to concentrate the sun’s energy and convert it into electricity.
• Solar hot water and space heating and cooling: Solar collectors use the sun to heat water or a heat-transfer fluid which is stored and used for domestic hot water heating and hydronic space heating.

Are solar cells a new technology?
No. Modern solar cells with practical efficiency were invented in the early 1950s, and have been used to power satellites since 1959. They became popular for terrestrial applications in the mid-1970s, mostly for remote telecommunications, navigational aids and other rugged, remote industrial uses including microwave, TV, radio and cellular repeater stations. They have been powering urban applications such as roadside emergency telephones and traffic signboards since the mid-1980s. With increased demand, prices have dropped to where solar panels are now becoming affordable for homes and businesses.

Are solar electric systems safe?
Yes. Solar cells are mostly silicon, the primary component of sand. There is no exhaust and no toxic materials to leak out of the system. The electricity coming through the inverter is just like the electricity coming from household wall sockets; you should use the same care you would with utility power. All components are approved for utility interconnection and are installed according to standard construction practices.

Are solar power systems good for the environment?
Yes! Energy created through our Solar Energy System produces no pollutants. Our smallest system typically cuts greenhouse gas emissions by the equivalent of 50 trees.

What do the terms on-grid, grid-connected, grid-tied and off-grid mean?
On-grid, grid-connected or grid-tied means the system is connected to the utility electrical grid. Powell Energy and Solar, LLC’s Solar Energy Systems are designed as grid-tied systems. Off-grid refers to systems that are not connected to the utility electrical grid. Our Solar Energy Systems are not normally designed for off-grid applications. An off-grid system must be designed to function without the support of the utility electrical grid and provide 100% of the needed electrical power.

How do I know if a residential solar electric system would work on my home?
Solar electric power works for almost any home. Our systems are engineered to work with most roofing materials and in most locations where direct sunlight is available. Our smallest system requires about 120 square feet of sunny roof area and our larger systems can require up to 1,000 square feet or more of roof space. 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 with a minimal decrease in performance.

Does solar work for commercial buildings?
Yes. Solar power systems are perfect for office buildings, retail buildings, schools, and government facilities; anywhere electricity is needed can use solar electricity. Oftentimes, the large flat roof of a commercial property is perfect for a concealed and easily installed Solar Energy System.

How many solar panels do I need to produce enough electricity to run my house?
Each home is different and the amount of electricity you use is very dependent upon your lifestyle, how your home was built, and your appliances. The array size will be dictated by  your average electrical usage, climate, roof angle, roof area, shading factors and other issues. To approximate the array size you need, add the number of kilowatt hours for each month from your utility bills for 12 consecutive months. The result is the approximate size of solar array, in kilowatts, needed to meet your electrical demand. Powell Energy and Solar, LLC will come to your home or business to evaluate what size system will work best for your needs. In addition to installing your system, Powell Energy and Solar, LLC can help you reduce your electricity use by making energy efficiency improvements to your home or business.

What is net metering?
In New Jersey, as in several other states, the utilities are required by law to provide “net metering” to Solar Energy System owners.  Net metering measures the difference between the electricity you buy from your utility and the electricity you produce with your Solar Energy System. With net metering, any excess electricity produced by your solar energy system is sold back to the utility grid, effectively spinning your meter backward. 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 between what you generate and what you take from the utility grid. The result is your “net” bill. Because the meter is subtracting electricity you would otherwise buy, you are selling the electricity to the utility at exactly the same price they are selling it to you.

Do I need batteries with the system?
No. Batteries are only required if you want or need  backup power when the utility is out of service. Without batteries, the system has no way to store power and for safety reasons cannot produce power when the utility grid is not in operation.

Are the solar panels fragile? Can they withstand wind and hail?
No. The panels are supported by a engineer-designed mounting system that has been tested to withstand high winds and can work on almost every type of roofing material. The panels are made of tempered glass (the same as a modern car windshield), and are impact tested to withstand snow, ice, wind and moderate hail storms. For example, one manufacturers modules are tested to withstand one inch (2.5 cm) hailstones at 50 mph (80.5 kph). Panels generally have a 20 or 25-year warranty and are even installed in extreme Arctic and Antarctic locations.

How long will the system last?
Solar panels have no moving parts so they are not very prone to failure. While most of the current designs have not been in service long enough to confirm this, it is commonly thought that panels should last for 40 yrears or more. Most panels have a 20 or 25-year power warranty from the manufacturer. Inverters typically have a 10 or 15 year warranty. In addition, the system is generally warranted for 5 years against all defects by the installing contractor.

How well do solar module withstand, and work in, inclement weather?
On cloudy days, solar modules work, although they produce less electricity than on sunny days. Under a light overcast, the modules might produce about half as much as under full sun, ranging down to as little as five to ten percent under a dark overcast day. If the modules become covered with snow, they may stop producing power but snow generally melts quickly when the sun strikes the modules. When the snow comes off, they resume operation immediately.

Do I need to install a new roof before the solar panels are installed?
Most installations do not require a new roof prior to PV installation. Solar panels will last many years (over 25). Because of this, it is ideal that your roof is in good condition, as working around the Solar Energy System will add complexity to a future roof replacement. However, after the panels are in place, they will greatly reduce the wear on the roof by blocking ultraviolet rays and by keeping most of the snow and ice off the roof. Due to our association with Powell Building Corporation, we can provide an expert assessment of your roof’s condition while evaluating your home for a solar panel installation and combine it with the Solar Energy System installation if necessary.

Do I need a building permit?
Yes. We will 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 standards as detailed in the National Electrical Code which our systems must comply with.

Can I have a solar electric system on my house and still be connected to city power?
Yes. Our systems are designed as grid-tied systems, meaning they are designed to interconnect with utility power providing seamless electric power to your home or business. You will never know you have a Solar Energy System until you open your monthly utility invoice.

If I sell my property, what effect does a PV system have on the sale price?
Installing a Solar Energy System to your home can substantially increase its value. This value will only grow as utility costs increase in coming years.

Are there financial incentives for buying solar electricity?
There are many incentives for purchasing a Solar Energy System. These vary from state-to-state. Some common incentives include:

• Net metering, which means that you can get paid by the utility company when you generate more power than you use
• Higher resale value for your property
• Federal tax credits
• State rebates
• Income from the sale of Solar Renewable Energy Credits (SREC)
• Decreased utility costs which will increase as utility cost rise
• Very favorable depreciation schedules for commercial systems

State programs (including NJ, NY, CT, MA, DE, RI, ME, PA, MD) provide funding to decrease the upfront cost of solar electric photovoltaic systems. We will help you procure funding from your state.

How long does it take to install a PV system?
Typical residential systems take from 2 to 5 days to install. Systems mounted on the ground and systems with batteries are more complex, and may take longer. Most of this time is spent outside your house, so there is little disturbance to you. Commercial systems can take longer to install depending upon size and type of installation.

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