Features of a Quality Solar Installation

    First of all, this article is intended to inform solar energy system buyers so they will know what to look for in a quality solar (PV) installation.  There are many highly qualified solar installers in the industry, but here are some observations.  The solar industry is relatively new to the United States.  By default, a large number of solar contractors and/or installers (like any other type of  business) are start-up companies with little or no experience in the industry.  In my home state of Texas, there does not exist a solar installer license.  Instead, the law in Texas defines a solar (PV) installation as electrical work, and electrical work may only be installed by a  state licensed electrical contractor unless otherwise excepted under the law. More specifically,  a person or business may not perform or offer to perform electrical work or residential appliance installation unless the person or business holds an appropriate license.  The state has ruled that installing (or offering to install) a solar array requires a Texas Electrical Contractors license.  An exception is that solar mountings can be installed by unlicensed individuals provided the mounting system does not have an integrated wireway.  

    Longevity for solar startups is no different than for any other startup business.  Most are out of business the first year.  Most of those who survive the first year are out of business after three years.  This means you may have trouble getting problems corrected (such as safety or fire hazards), or getting service or warranty repairs after the installation.  Established electrical contracting companies are becoming interested in solar, however, this does not assure a quality installation.  Solar installations have unique characteristics that most electrical contractors aren't familiar with.  Here are some suggestions that might be helpful in choosing the right contractor for a solar energy project.

Choose your solar contractor carefully.

    Ask some very important up-front questions such as:

    - Does the company have a member who is a NABCEP (North American Board of Certified Energy Practitioners) Certified PV Installer?

     - Is the contractor licensed and insured?

     - Have they performed both electrical and solar installations (a licensed electrical contractor who is also experienced in solar installations is a plus)?

    - Are references available?

    - Are they approved for solar rebates by participating utility companies or government agencies?

    - Where does the solar contractor get his equipment and materials?  Is it from a reputable source?

Before you sign.

    After carefully choosing your solar contractor, the process requires a few simple steps before a system can be installed (and before you should sign any contracts).  These steps (in order) are:

    - System Design.  Whether your solar contractor is designing your system or you are going through an architect and/or electrical engineer,  have your solar contractor involved in the design process from the very beginning.  A good solar contractor will make sure the solar energy system and structure compliment each other.

    - Site Survey and Analysis.  Ask for the results of the preliminary site analysis.  Your solar contractor should evaluate your location for such things as shading, roof design and age (in the case of roof-mounted systems), location and size of electrical service, location of obstacles (such as air conditioning equipment, roof vents, windows, etc.

    - Home Owners Associations, landlords and Ordinances.  After you have your design completed, get all approvals from homeowner associations, landlords and your local municipal jurisdiction IN WRITING.  You should have assurances that you will receive a written approval before you even contact solar design and installation companies.  In our experience, there may be some resistance to something new and unfamiliar, such as a solar array.  Your solar contractor should be available to assist with these approvals and answer questions from local approval authorities.

     - Nail down the specifications.  Get a written list of what you expect and have your specifications included in the contract.  A good solar contractor should provide you with specifics, but allow them to recommend equipment and design.  This will help you weed out those who don't have a clue what they are doing.  As a minimum, you should receive written (published) manufacturer specifications for your inverter, solar panels and mounting system.   Equipment comes from a variety of sources, and some are top-of-the-line, while others are on the low end of efficiency and dependability.  Where the equipment is made is not as important as who makes it and how it is made.  The California Energy Commission has a comprehensive list of equipment approved for California state rebates.  Many locations outside of California have adapted the "CEC" list for their local rebate programs, so make sure the equipment recommended by your solar contractor is on the CEC list.  If it isn't good enough to make the list, you don't want it on your property.  The list includes the CEC rated efficiency of the equipment, so you can make comparisons and evaluate the quality of the equipment you are buying.  The CEC is a rating based on typical California temperatures and solar availability (irradiance) while the nameplate ratings are based on Standard Test Conditions (25 degrees C at 1000 watts per square meter of solar irradiance).  The price difference between the best and the worst on the market isn't that much different.  Considering the expense of any system, you might as well invest in something that will last and produce the most electricity possible.  You can review the CEC list at:  http://www.gosolarcalifornia.ca.gov/equipment/ .

    - The electrical interface.  First of all, no one other than a licensed and insured electrical contractor should perform the electrical work required for a solar energy installation.  Most municipalities and some states require this, however, many rural areas do not fall under licensing jurisdictions (Texas licensing law extends to rural as well as urban areas).  The National Electrical Code has a number of acceptable electrical  techniques for installations, but the value in safety, performance and appearance can vary widely.  One unacceptable short-cut is in wire and disconnect sizes.  Again, if your contractor is offering a "cheaper" system, then there may be some electrical short-cuts involved.  Regardless of the installation method, all electrical installations must be accomplished in a manner that is "neat and workmanlike."  (A good article on acceptable standards can be found at:   http://www.iaei.org/magazine/?p=4321.)  Some examples of acceptable electrical installations are:

        -- Commercial standard.  All conductors are in conduit and metal enclosures.  Conduits may be galvanized rigid (GRC), electrical metallic tubing (EMT), metal clad cable (MC), or PVC (in the case of underground conduits).  Disconnect switches are rated NEMA 3R for outside locations and NEMA 1R for interior locations.  For larger commercial projects, the disconnect switches should be service rated.  All conductors---from the solar array to the utility company meter must be electrically protected by some means (either by fuses or circuit breakers).  Conduit bending is an art and if done correctly, can add significantly to the overall appearance and value of a system.  Conduit runs should be either level, or perpendicular to level.  Conduits running adjacent to each other should be parallel.  All conduits and enclosures must be securely mounted using only approved mounting methods.

         -- Industrial standard.  Similar to commercial except that galvanized rigid conduit and fittings are used and service equipment is service rated.  This standard is expensive and in most cases far exceeds what is required for most quality installations.  These standards would apply in areas where there is a likelihood of physical damage or where hazards may be present (such as flammable gases, dust or other considerations identified by the National Electrical Code) .

         -- Residential standard.  This standard is common for homes but variations may be found in some commercial applications.  The most notable difference is in the use of non-metallic cable (or Romex), plastic enclosures, and PVC types of conduits and fittings.  Wire runs tend to be circuitous (freeform) with sweeps and random angles.  Disconnecting means are built from lighter gauge metal.  Conductors in outside locations may be enclosed in a flexible PVC conduit known as "Seal Tight" or in PVC, as opposed to metal conduits such as EMT or RGC.  This is the cheapest method of all electrical installations and does not require a great deal of skill.

Note:  For all installations, the system must be well grounded to protect against electrical damages and electrocution.

    - The time to find out your system doesn't qualify for a rebate is before it is built---not afterwards.  Make sure all approvals are in hand before you allow any money to change hands.  Not all areas have solar rebates so check the rules that apply to your location and utility services.  All utility companies have rules for tying into their grid---get their "ok" early on.

    - Although it isn't a code requirement, a professionally installed rooftop system will have the solar array centered (to the extent possible) on the roof.  For all systems, building codes require a mandatory "clear" area on the roof borders.  This is for safety, fire protection access, and wind loading (in the case of top and sides of a roof).  There will be no visible wires either on the roof or from the array to the utility company meter.  For ground mounted systems, all wires between separate groups of panels and from the array to the metering equipment will be enclosed in conduit and the conduit buried 24 inches deep in a trench.  

The construction contract.

    A good agreement will cover all of the basics:

    - How much will the system cost

    - When will it be accomplished

    - How and when will it be accomplished (the specifications

    - How will it be warranted

    - What are the payment terms and conditions

    The more complex the system and higher the price tag, the longer the agreement will end up becoming.  A simple system contract may be three or fewer pages (not counting specification addendums).  If you don't understand contracts, it never hurts to have a competent attorney look it over before you commit.

Terms and financing.

     I have never been comfortable paying for something up front--especially something as expensive as a solar energy system.  However in the case of solar, suppliers often demand that installers make full payment for the equipment at the time of the order.  This alone can be over 75% of the total system cost.  For the installer, requiring a significant up front payment reduces or eliminates their risk of a customer defaulting, however it likewise increases the risks to the customer if the installer defaults.  This is where it is very important to check the past history of the installer.  You don't want to find out your installer and money have gone on a permanent vacation.  If you believe your solar contractor is legitimate, require the equipment to be delivered directly to your location from the contractor's supplier.  At least you will have possession of the equipment and hopefully you will also save back a significant portion of the contract amount until after the system  has been inspected (and passed) and has been commissioned (placed in operation).  An alternative to a sizable down payment would be to go through a lender for a loan then require the solar contractor to obtain a construction loan to cover his expenses.  This alternative has the added feature of placing the lender in an oversight role for the funds.  The contractor gets nothing from you until the system is commissioned and the lender is satisfied with the installation---but at the same time, the contractor and their lender are assured the bill will be paid upon completion.  Should you choose to forego a loan for the project, it might be a good idea to provide the solar contractor with a bank letter of credit in lieu of cash.  The letter of credit is a bank guarantee to the contractor that funds are available and will be paid unconditionally after all contract terms are met.  With a letter of credit in hand, the solar contractor would then be able to obtain construction financing on their own.  One note on Letters of Credit.  The cost of the Letters of Credit are on the customers' shoulders.  If you find a reputable solar contractor, it is less expensive and expedient to pay the up front payment.  You'll need to decide the best approach based on your experience and circumstances.

Summary.

    You are investing a sizable amount of money in a system that should last a lifetime.  Does it make sense to go with the low bidder if it means getting a poor quality system?  Ask questions--it's your right to do so.  Do a thorough background check on at least three reputable solar contractors.   Although your area may not require solar contractors to be licensed electrical contractors, the fact is a licensed electrical contractor has to go through a much more difficult qualifying process than a contractor who is just a solar installer.  In the State of Texas (where I am qualified to discuss the subject), there does not exist (at the time of this writing) a licensing program specifically for solar installers---all solar installers by law must be licensed electrical contractors in Texas.  There is, however, a voluntary national certification program that requires four years of experience installing solar or electrical equipment, 40 hours of classroom instruction, and passing an exam on solar installations (with a significant portion of the exam based on the one-thousand-plus page National Electrical Code).  Only about 30% of those nationally who take this exam pass it.  To become an electrical contractor you must either be a Master Electrician or hire one.  It takes eight years of documented electrical experience in most jurisdictions just to be qualified to take the Master Electrician exam.  The exam is an in-depth national standardized test covering the entire National Electrical Code.  The exam can take over six hours to complete---most journeyman electricians fail the test the first time they take it; many never pass it.  Once the test is passed and the Master Electrician license awarded, it then takes several more years to reach the level of electrical contractor.  The typical electrical contractor (according to lenders) has a business lifespan of less than one year.  Finally, after you are convinced you are dealing with professionals who will be around to service your equipment for five years or more (the common warranty period for inverters is five to ten years), choose the solar contractor based on VALUE not price.  Not only will you get better service and longevity from your system, you will see a return on your investment should you sell the real estate it is built upon.

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