PV System Basics

The basic building block of the photovoltaic (PV) energy system is the solar "cell". A number of cells are connected together to make the PV "module". A number of modules are then combined to form a photovoltaic "array" capable of supplying the entire energy needs of your home or business.

The typical PV system consists of an array of modules connected to an inverter that changes the direct current (DC) electricity created by the modules to an alternating current (AC) which then ties into your local utility's electric grid. Optionally, a battery back-up system can be used for reliable generation of electricity if the utility grid goes down, protecting your home or business from power outages.

Utility Grid Tie-in, Utility Rules

> What is an Interconnection Agreement?

Interconnecting your PV system to the utility transmission grid will require you to enter into an Interconnection Agreement with your local utility. Upon approval of an installation contract with SOLectric for your system, we will assist you by providing the proper PG&E interconnection forms for your signature.

After the system is installed and inspected by your local building department, there will be a waiting period before PG&E performs their final inspection of the installation. PG&E rules prohibit the use of the system during this waiting period. For more information see PG&E.


Net metering allows your electricity meter to spin forward when electricity flows into your building and also backwards when your PV system produces a surplus of electricity that is not immediately used. Your meter will add up all of those additions and deductions like a calculator Your excess electricity is "banked" on the utility grid. You can use an equivalent amount of electricity later without cost to you. All utilities in the state of California are required to offer owners of PV systems the option of interconnecting with the electrical power grid on a net-metering basis. See PG&E's web site on NET METERING.

The Time of Use option (TOU) PG&E billing rate E-6:

Buy low, Sell high:

With a time of use meter you pay less for electricity during off peak hours 7PM to noon than you pay for peak hour electricity from noon to 7PM. This is because it is more expensive to produce electricity during peak energy use. With a time of use meter you are more closely paying the true cost of electricity. Your PV system produces more electricity during the peak energy use when no one is home, so you will be reducing your bill faster than during off-peak periods. Call us to evaluate your situation.

There is a modest one-time utility charge for the TOU meter. We will assist you in applying for the TOU rate.

Site Suitability

> Will my home or business site work with a PV system?

The best orientation for a PV system is a roof facing between south-east, south or south-west. We will come to your house to measure available solar access. If a rooftop cannot be used, your PV array can be mounted on a patio cover, horse barn, pool cabana, pole, on-ground rack or other structure for maximum power generation. Your photovoltaic modules should have a clear, unobstructed access to the sun throughout the year to make the best use of your PV system. The photovoltaic array should be free from shading by nearby trees, chimneys, buildings, etc.

Shading will reduce the amount of electricity your PV system will produce. When we come to your site for an evaluation we will establish its suitability. Please contact us via our Questionnaire.

What does it cost?

Unlike an appliance purchase, each photovoltaic installation is unique. Each site has conditions that determine equipment choices, configuration, and costs. After a site visit we will develop a cost estimate for your specific solar energy investment.

Installation for a home with these features:

  • Single story home
  • A new roof will be installed
  • The new roofing will not be clay or cement tiles

Will cost less than a home with these features:

  • Multiple story home
  • Mounting on existing roofs
  • Flat or clay tile roofs

For larger systems above 8kW, the cost per watt will be slightly lower, all other conditions being the same. Please contact us via our Questionnaire or call (650) 248-1216.


The California State legislature, along with the California Energy Commission (CEC), have enacted the Emerging Renewables Buy-Down Program, to help reduce, or "buy-down" the up-front cost a consumer will pay to purchase and install a system utilizing emerging renewable energy technologies, such as solar photovoltaic. Buy-down amounts are based on the generating capacity of the system, measured in watts.

The program, currently (as of 9/06) offers a rebate of $2.60 per watt, or 50% of the purchase price, whichever is less. For example, a 2500 watt system will receive a rebate of $6,500.00.

The rebates are reduced 20 cents per watt every 6 months. We recommend contracting now for a system to get the most rebate. The Energy Commission will review your application for eligibility and send you a Rebate Payment Claim Form. Your system must be installed within nine (9) months of the confirmation date for systems that are less than 30 kilowatts (kW).

For more information on the California Emerging Renewables Buy-Down Program, see the California Energy Commission web site.

Palo Alto and Santa Clara Utility customers receive rebates from their respective utility departments. We handle applications for those utilities, also.

Call us (650)-856-1735.

Tax Credit

The Federal tax credit of 30% of the net cost of a photovoltaic system, after any other rebates, is capped at $2,000.00 for residences.

The tax credit for investment in business photovoltaic assets is 30% of the system cost. Please consult your tax advisor for information on how to apply for the Tax Credit.


Manufacturers provide up to 10 years on inverters and up to 25 years on Photovoltaic modules. We provide a 5-year warranty on CEC form 1038-R3 which is required to claim the maximum rebate.


What will it save me? Payback time. Estimate my solar energy system. Call us for assistance in using the Estimator: (650)-856-1735.

Building Permits, Insurance

What should I know about permits and codes?

Nothing! SOLectric will obtain all necessary permits for your PV system from the local city or county building department before installation of your PV system. All SOLectric PV systems comply with Article 690 of the National Electrical Code that lists requirements for the design and installation of safe, reliable PV systems.

What about Insurance Requirements?

As part of your interconnection agreement, your utility may specify minimum insurance requirements. California law, however, does not allow a utility to require the purchase of additional insurance (California Public Utilities Code 2827-F) A standard homeowners or business insurance policy may be adequate to meet the utility's insurance requirements.