Frequently Asked Questions
Solar Technology FAQs
Solar energy benefits you and the environment, and it’s a good way to contribute to energy sustainability. You can reduce your monthly electric bill, receive rebates to subsidize the system cost and also play an important role in moving the state toward a cleaner energy future.
Solar electric or PV technology uses the sun’s energy to make electricity. When sunlight strikes an array of solar panels, electrons are freed by the interaction of sunlight with semiconductor materials (typically silicon). The movement of electrons creates current, thus creating direct current (DC) power.
DC is the only type of current produced by solar cells. Appliances and machinery, however, operate on alternating current (AC) as supplied by your utility. The DC energy produced by the panels is fed into an inverter that transforms the DC power into AC power, which then feeds into the main electrical panel that powers your house or business.
A bi-directional meter connected to the electrical panel measures both the amount of electricity your system is producing and how much electricity you are consuming.
First consider how much sunlight your property receives. Your property should have a clear, unobstructed access to the sun for most of the day, and throughout the year.
In California, the sun is in the southern half of the sky and produces more PV electricity than in the northern part. Because shading will reduce the amount of electricity your system will produce, PV panels ideally should be installed in a location that is not shaded by trees, chimneys or nearby structures.
The best orientation for a PV system is on a south- or southwest-facing roof. Flat roofs can also work because the PV array can be mounted on frames tilting south or southwest. In addition PV array can also be mounted on the ground.
The amount of roof space needed is based on the size, or generating capacity, of the solar energy system. Residential solar energy systems can vary in size from 50 square feet to 1,000 square feet. A rule of thumb is that a square foot of PV module area produces 10 watts (W) of power in bright sunlight. For example, a 2,000 W system would require about 200 square feet of roof area.
Several factors will influence the size of the solar electric generating system. The first step in determining the appropriate size is to conduct a free energy efficiency audit and implement measures to reduce the amount of electricity you need. The second step is to review your previous 12 months of electricity usage. Typically, solar installers and contractors will be able to help you with these steps.
For CSI systems the average residential solar energy system size in our service territory is about 5 kilowatts (kW), and the average non-residential solar system size is 262 kW. The CSI program allows customers to size a solar system up to their previous 12 months electrical requirements, but in most cases homeowners only need to size a system to avoid the upper three billing tiers.
In California, a PV system will produce the most electricity in spring through fall when sunlight hours are the longest and the sun is positioned higher in the sky. A 1-kW system can produce from 1,400 kilowatt-hours (kWh) to 2,000 kWh per year depending on the location within the state. Generally, a PV system in Southern California will produce more electricity than one in Northern California.
A kW is a basic unit of measure of real electric power or a rate of doing work. A kW is 1,000 W.
A kWh is a basic unit of energy consumption. For example, ten 100W light bulbs burning for one hour will consume 1,000 W-hours, or 1 kWh of electricity.
A. The cost varies depending on many factors, including the solar energy system’s size, equipment options and labor costs. Typically, the installed costs are determined based on the size of the system’s output. The “cost per watt” ($/W) is often used for comparing systems of different sizes.
It is difficult to predict how much an individual system will cost. Visit California Solar Statistics to find out the current average $/W for systems installed through the CSI program.
The California Solar Rights Act, enacted in 1978, limits the ability of covenants, conditions and restrictions (typically enforced by homeowners associations) and local governments to restrict solar installations. Get more information on the California Solar Rights Act.
Yes. PV output can be impacted by dirt accumulation. The frequency of cleaning depends on the location. For example, locations closer to freeways or industrial facilities, or in high-wind areas are likely to accumulate dirt more rapidly and should be cleaned more frequently.
No, a solar generation system operates automatically, and shuts itself on and off automatically.
If a power outage occurs, your solar energy system is designed to immediately shutdown for safety reasons. A grid-tied solar electric system does not provide power during outages unless it includes a battery storage system. Your power will be reinstated moments after grid power is restored; however, you may need to manually reset your solar system’s inverter back to service after your power is reinstated (most auto reset after power is restored).
Yes, it does. The customer must pay up-front costs for the solar photovoltaic (PV) equipment and installation; however, Multifamily Affordable Solar Housing (MASH) incentives, federal investment tax credits, renewable energy credits and net metering credits can significantly reduce the customer’s cost of PV equipment and installation. Each project will have a different payback period depending on the type of financing that the customer uses to fund the project.
|Incentive Track||Incentive Budget|
|Track 1 A/B||$34,656,032|
* In D.11-07-031, the CPUC shifted all remaining funds from Track 2 into Track 1. Statewide, approximately $8.1 million was awarded to Track 2 projects. Any reduction in incentive payments will be applied to Track 1.
A. To learn more, go to the California Law homepage and search for the code section.
The MASH Program allows customers to enter into PPAs with third parties if the terms and conditions of the agreements comply with all existing statutes and regulations that govern the production and sale of electricity.
A. California Health and Safety Code Section 50079.5 defines “lower income households” as follows:
(A) "Lower income households" means persons and families whose income does not exceed the qualifying limits for lower income families as established and amended from time to time pursuant to Section 8 of the United States Housing Act of 1937. The limits shall be published by the department in the California Code of Regulations as soon as possible after adoption by the Secretary of Housing and Urban Development. In the event the federal standards are discontinued, the department shall, by regulation, establish income limits for lower income households for all geographic areas of the state at 80 percent of area median income, adjusted for family size and revised annually.
(B) "Lower income households" includes very low income households, as defined in Section 50105, and extremely low income households, as defined in Section 50106. The addition of this subdivision does not constitute a change in, but is declaratory of, existing law.
(C) As used in this section, "area median income" means the median family income of a geographic area of the state.
To learn more, go to the California Law homepage and search for the code section.
MASH has two incentive tracks – Track 1 A/B and Track 2. Currently, Track 1 offers $1.90/Watt for a system that offsets common load and $2.80/Watt for a system that offsets tenant load. These rates apply to MASH applications that are placed under review on or after July 14, 2011. This rate is consistent across the three utilities. Unlike general market CSI, MASH does not have a declining rate based on volume of megawatts of confirmed incentive reservations issued in SCE’s service area. Track 2 is no longer available. Currently, the only incentive type available for the MASH Program is the Expected Performance-Based Buydown (EPBB).
Eligible electric customers of PG&E, SCE and SDG&E may receive an incentive through the MASH program. In addition, all existing multifamily affordable housing must meet the definition of low income residential housing established in Public Utilities Code § 2852.a.2.
Specifically, this means multifamily housing financed with low-income housing tax credits, tax-exempt mortgage revenue bonds, general obligation bonds, or local, state or federal loans or grants. The facility must also meet the definition of low-income households in Health and Safety Code § 50079.5.
Planned new housing construction, including new housing development projects and new custom homes, may be eligible for the New Solar Homes Partnership program. The Single-Family Affordable Solar Homes (SASH) Program, which is intended for homeowners who qualify for low-income housing programs is also available. For more information about SASH, contact the program administrator - Grid Alternatives
A. In addition to rebates available through MASH, your project may also be eligible for a federal tax credit. Consult the IRS or your tax consultant for details on available tax credits. For additional information, visit the Database of State Incentives for Renewables and Efficiency, DSIRE. For the most current status of these tax credits, you should contact the Internal Revenue Service and/or your tax preparer.
MASH incentives are available for PV technologies (roof-mounted, ground-mounted and building-integrated PV) sized to meet the site’s previous 12 month’s on-site electrical usage.
Incentives are now available for solar water heating systems in SCE’s service area. For more information, see the Solar Thermal Rebate Page
For most projects, the installer takes care of the application for the customer when applying for Track 1 incentives. Applications proceed through three simple steps: (1) Requested, (2) Reserved, and (3) Completed. Qualified installers understand the application process and can optimize customers’ incentives by completing the application and submitting all required documents.
Generally, MASH applications go through the three-step application process. However, applicants can opt-in to the two-step process, although the requirements detailed in the three-step application process still apply to the project.
For MASH applications placed under review on or after July 14, 2011, an application fee is required for systems that are 10 kW CEC-AC or larger. Check the CSI Handbook for more details.
For Track 1, your installer can provide you with regular updates regarding the status of your application. You can also contact us at (866) 584-7436 to get project updates.
SCE strives to confirm MASH Track 1 reservation requests in less than 30 days. Application processing time depends on a number of factors, including the speed with which applicants respond to requests for more information or provide corrections to applications.
To avoid delays, avoid the following issues: missing energy efficiency audit; listed equipment does not match EPBB tool calculator printout; copy of executed contract for system purchase and installation; missing signature(s); and incomplete or missing documentation.
MASH applicants are given a reservation period of 18 months to complete their project.
Yes, you can apply for both Track 1A to offset common load and Track 1B to offset tenant load. The system for the common area must be sized so that the system primarily offsets part or all of the common area’s electrical needs. Tenant areas will be aggregated for sizing limits. For example, up to 50 kW of a system may be allocated to 10 units in a building without requiring system size justification because the average will be 5 kW or less.
Installed systems must be field-verified to verify that the installation of high-performance PV systems are consistent with the information used to determine the estimated performance, reservations and the final rebate.
A. SCE hosts monthly Introduction to the California Solar Initiative classes. The class is not specific to MASH, however it can provide attendees with a general understanding of PV systems. For more information, visit the following webpage: Solar Classes
You will probably need to obtain a permit from the city or county building department. A solar vendor/installer may be able to assist with this.
Qualified contractors are your key to getting the most productive solar generating system for your site. Choose a reputable installer by interviewing at least three potential installers and obtaining bids before making your decision.
Except for systems that are self-installed, all systems must be installed by appropriately licensed California contractors in accordance with the rules and regulations adopted by the California Contractors State License Board. All systems must be installed in conformance with the manufacturer’s specifications and with all applicable electrical and building code standards.
NEM and Interconnection FAQs
No. The MASH program only provides incentives to grid-tied solar systems, thus MASH participants are not off-grid. Instead, MASH systems generate electricity that flows back onto the grid, from which the MASH participants draw energy whenever their solar generating systems are not generating energy.
Connecting your solar generating system to the utility grid will require that you to enter into an interconnection agreement with your utility. SCE has a standardized interconnection agreement that includes the terms and conditions under which your system will be connected to the grid and the technical requirements ensuring safety and power quality. Additional information and NEM Application Options are available.
Net energy metering (NEM) is a program designed to benefit customers who generate their own electricity. To qualify, eligible customers must produce energy from an electric generating system using solar, wind, biogas or fuel cell technology, or a hybrid generating system. The NEM program does not allow you to sell power back to SCE or into California’s wholesale electricity market.
The NEM program uses a bi-directional meter to measure and/or track the “net” difference between the amount of electricity you produce and the amount of electricity you consume during each billing period. This can be accomplished on a cumulative basis or on a time-of-use basis, depending on your rate schedule.
At the end of each billing period, you will receive a credit for any electricity you have generated that exceeds the electricity you have consumed. If your energy consumption is greater than your energy produced you will be billed for the net difference. You will be billed for certain other applicable charges whether or not you are a net energy metering customer. At the end of each 12-month period, you will either owe a balance for excess energy consumed or you will have the option to receive Net Surplus Compensation. Additional information on net energy metering is available.
The MASH Program requires accurate energy production meters for all projects that receive MASH Program incentives. We have a list of incentive-eligible solar equipment. Accurate measurement of solar energy output is important to ensure optimum value for both solar owners and ratepayers. For solar electric generating systems receiving an EPBB incentive, a basic meter with accuracy of ±5 percent is required. MASH projects will only receive EPBB incentives.
For M.A.S.H. Virtual net Metering projects a net generator output meter is required, visit SCE Tariffs for more information.
MASH applicants are not currently required to take service on TOU rates unless otherwise required by other terms of their service until the CPUC develops and makes effective TOU tariffs that meet the requirements of Public Utility Code Section 2851(a)(4). Entities that receive the MASH incentive after the new TOU rates are established must go on the new TOU rates. Many solar customers benefit from TOU rates because solar production replaces peak load and is credited to the customer at the higher-cost peak price.