Installation Tips
Inverters:
A humid environment will affect the life span. The ideal place to install an inverter is in a cool, dry, and preferably air-conditioned environment.
Roof:
Evaluate available roof area and roof condition.
You will need about 100 square feet of space for each kilowatt of photovoltaics and about 175 square feet per kilowatt.
Roof Mounting Clearance: Panels mounted on a roof should have at least an inch, and preferably 2 to 6 inches, clearance between the bottom of the panel frame and the roof. This allows for air flow under the panels for cooling. Panels should never be mounted so there is no air flow under them, as they can reach very high temperatures
Grounding:
A very important factor in PV installation is proper grounding. If not properly grounded, these metal surfaces can be energized at up to 600 volts when a ground fault occurs. Of primary importance are the aluminum frames of the modules, the metallic conduits used to carry the conductors, the disconnect enclosures and the inverter enclosures. (John Wiles, Institute for Energy and the Environment.)
While maintenance is minimal, expect to pay electrician rates if maintenance is required.
Quotes:
Ask them to size two systems for you. 1) one to eliminate your entire kWh usage and 2) one to eliminate all but your Baseline amount (Peak Shaving)
California Residents: 10 Tips for Hiring a Contractor
Hiring a contractor to install a PV system on your home or business is a major decision. The following tips will help you find the best contractor for the job.
1. Hire only licensed contractors
Check the contractor's license number by calling the Contractors State License Board at 1-800-321-2752 or visiting www.cslb.ca.gov.
See this article in Mother Earth News on "How to Choose an Installer." The article is old, but the general guidelines are still relevant.
7/9/2008 - Article on Solar Scam Artists.
2. Hire insured contractors
Always insist upon a certificate of insurance for general liability insurance. Uninsured workers who are injured on the job can file damage claims against the homeowner.
3. Verify Workers' Compensation Insurance
California requires this form of insurance for any employer with one or more employees. If your contractor is exempt from the workers' compensation requirement, it means any workers on the job must belong to another subcontractor who is insured.
4. Get references
Always get at least three references from previous customers of the contractor, and review past work.
5. Get multiple bids
Get three (3) bids and use a written plan, so you can compare apples to apples.
6. Get a thorough written contract before any work begins
Any work valued at over $500 requires a contract. In the contract, be sure to specify the start and completion dates of the job, and insist on a progressive payment schedule that is spelled out in dollars and cents. If you're going to spend thousands of dollars, consider investing another $200 to have an attorney review your contract for your protection. Make sure these costs include any necessary permits.
7. Never sign a contract under pressure
Insist on at least 48 hours to study any contract.
8. Pay as you go
To start a job, never pay more than 10% down or $1,000--whichever is less. Hold back 10% for the final payment after the entire job is complete. Never pay for work before it is done.
9. Never pay cash
Pay by check or credit card.
10. Keep a job file
Put receipts, permits, plans and anything else pertaining to your job in the file.
Source: California Contractors State Licensing Board
