Solar Panels Calculator

Solar Estimate – Online Guide!


  1. PRIVACY – Solar estimate without personal information.
  2. FLEXIBILITY – Make your own choices at your time.
  3. BEST PRICE – Cut off pushy salesperson commission.
  4. SAVING – Based on local electric rates, Rebates & Tax Credit.
  5. ACCURACY – Location based radiance data, roof and system performances.

*Get solar proposal, including roofing layout design and saving analysis within 24 hours. Solar Price Discovery specialist will review and revise (If needed).

SOLAR PRICE DISCOVERY solar panels calculator tool is real, friendly with advanced customize real world solar saving analyze tool.

Solar Panels Calculator - FREE Solar Savings Estimator - Residential solar panels cost

Create Your Own Estimate


Solar savings estimator – solar panels for your home cost

Types of estimates:

  • Online (Default): Based on your average electrical bills – Get solar estimate NOW!
  • Compare quotes: Based on solar system components preference – Get solar estimate NOW!
  • Do it for me: Upload electrical bills – Get solar layout & savings analysis within 24 hours!
  • Advanced Online: Based on solar system components preference; Site evaluation & True energy usage (Optional) – Get solar estimate NOW!

Online (Default)

“Online (Default)” – Default solar panels calculation option! This option is based on customer average electrical bills.

Solar Panels Price – average electric bill with solar panels


Zip Code (Input):

California Zip Codes Only.

The “Zip Code” used to match local solar irradiance. (By default, we use DT LA CA irradiance data base).

Utility (Select):

Will let you know if there might be utility rebates for solar panels installation or any other associated cost (If any).

Compare Quotes

“Compare Quotes” – Compare Solar Panels quotes.

Did you get solar bids? Tired of getting different solar panels quotas? Confuse with solar cost and solar savings numbers? This option allows you to select the number of solar panels, type of solar panels, and inverter. All you should do is to select this option and our system will tell you what is the actual solar system sizing, and the price you have to pay.


Do it for me

“Do it for me” – Let us do it easy for you!

Solar Price Discovery Inc solar energy specialist will review your bills and will send proposal to your email. Utility bill required.

Advanced Online

“Advanced Online” – Solar Panels preference and real-world adjustment

Based on solar system components preference; Site evaluation & True energy usage (Optional) – Get solar estimate NOW!

Customers need to be aware that in most cases are changing during the seasons, not only because their energy demand profile is changing but also because the most of the utility companies are charging you differently between the seasons per year. For accurate savings analysis, we are recommended to check the box “Customize your average monthly utility bills (Optional)”.

You can Fill in the blank your latest ELECTRIC USAGE (kWh) and ELECTRIC PAYMENT ($) to calculate your actual electrical payments or you can fill up to 12 month electrical bills for better results. (The order does not matter). The important results here will be your actual Pre-Solar cost per kWh. We will use it to analyze your potential savings.

Design your system, Select solar panels ad inverter brands, roof performance yourself – Get solar system estimate now!

System customization (Optional)

Site Evaluation

Changing the following parameters will effect the results above!
Don’t Worry! SOLAR PRICE DISCOVERY specialist will review and revise (if needed) for your convenience.

Site Planning

  • Mounting Method – Refer to the solar installation method. Roof top solar installation or ground mount solar installation.

  • Roof type – Refer to the complexity of the solar installation, based on the roof materials (Asphalt Shingles, Clay Tile, Slate Roof, Wooden Shingles, Metal Roof and Flat Roof.

Solar Panels Calculator - mounting solar panels on shingle roof

  • Tilt – The tilt angle of your roof. The optimum angle for sun exposition is based on location earth latitude. In California, we will install the solar panel parallel to your existing roof tilt.

  • Azimuth – The Azimuth angle of your roof. Southern areas of solar panels installation will be exposed for more sun light. Therefore, we still get 80 to 95 percent roof performance when installing the solar panels on the South-East-West combinations. North face solar panels installation isn’t recommended, but can be solved by tilting the solar panels toward the south.

You can get assistance by checking the box “How to find my longest roof pitch azimuth?” and following the Instructions.


  1. Input your address in the blank bellow the map.
  2. Zoom-In to locate your roof (Satellite view).
  3. Look for your longest roof pitch.
  4. Match your longest roof pitch to the compass on the left.
  5. Select the appropriate “Azimuth” from Drop-Down box.


Shading Estimate

Shading Estimate caused by buildings or trees. This option will let include the potential solar energy production losses cause by shading. This is an estimate only. Our specialist will determine the actual shading effects for you, based on solar location on your roof.

  • No Shading (~1%) – Solar panel performance losses of 1% – Default.
  • Minimal (~5%) – Solar panel performance losses of 5%.
  • Alternately (~15%) – Solar panel performance losses of 15%.
  • Frequent (~30%) – Solar panel performance losses of 30%.


“Main Panel Upgrade”

An Electrical panel of at least 125 amperage (Amp) required for adding solar to your home.

Your total electric devices shouldn’t increase the total Amp of your main electric panel. The total Amp is printed near or on the Main Breaker at the upper level of your electric panel. You can determine your total Amp here, or leave it empty, and we will calculate it for you later.

Main Panel Upgrade

“Main Panel Upgrade”

An Electrical panel of at least 125 amperage (Amp) required for adding solar to your home.

Your total electric devices shouldn’t increase the total Amp of your main electric panel. The total Amp is printed near or on the Main Breaker at the upper level of your electric panel. You can determine your total Amp here, or leave it empty, and we will calculate it for you later.

Solar panels

Solar Panels

(A Solar panels designed to absorb the sun’s rays for generating electricity)

Select your preferred solar panel brand and model. You can watch solar manufacture introduction video, read the panel specification and warranties for each of them.

Solar Panels Price - Best solar panels for home use - How many solar panels to power a house

Solar Panels Selection:

  • SolarWorld: High-performance, superior quality. Made-in-the-USA. SolarWorld‘s Sunmodule solar panels are designed and manufactured to the highest standards of quality, performance and durability. Source:
  • QCells provide uncompromising quality that outperforms the highest standard. Source: – Specification – Warranty
  • LG: Global leader in consumer electronics. Global leader in consumer electronics. LG can now offer superior solar products. The trusted LG brand provides innovative products and has built a reputation on quality and reliability like no other brand. Source:
  • CanadianSolar: High-quality solar panels since 2001. Founded in 2001 in Canada, Canadian Solar operates as a global energy provider with successful business subsidiaries in 24 countries on 6 continents. Source:



(Solar Inverter converts the direct current – DC output of a solar panel into an alternating current – AC)

Select your preferred inverter. You can watch manufacture introduction video, read the specification and warranties for each of them.

Solar Panels Calculator – PV Inverter – Home solar system kit


You can select one of the following inverters:

  • SolarEdge: The SolarEdge power optimizer is a DC/DC converter which is connected by installers to each PV module or embedded by module manufacturers, replacing the traditional solar junction box. Source:
  • EnphaseMicroinverters offer the most advanced inverter technology on the market, which means higher production, greater reliability, and unmatched intelligence. Source:
  • SMA: As a system technology specialist, SMAhas been developing and distributing high-quality PV inverters and innovative technology for intelligent energy management for over 30 years. Source:



Solar performance Tracking App to your smart phone or computer.

Solar Panels Price – PV Monitoring maintenance portal

Solar price Discovery Inc. will monitor your system and check for maintenance requirements.

Storage Battery

“Storage Battery”

Our energy storage solution (ESS) supported application are:

  • Energy Backup.
  • Self-Consumption of Solar PV Power.
  • Time of use load shifting.
  • TOU arbitration.

Solar battery storage calculator - Solar Estimate Online

Supported calculator available here: Battery Sizing ToolSolar Panels Sizer Tool – Load calculator Tool.

Solar Calculator - Results Keywords

Solar Calculator

Results Keywords

Pre-Solar Price: “Blended electric price $/kWh” is: Blended “Electric price $/kWh” is the amount of your total bill payments divided by the total kilowatt-hours consumed.

Post-Solar Price: “Post-Solar Cost” & Levelized Cost of Electricity (LCOE), is the net cost of the solar system divided by the sum of electrical energy generating over the lifespan, under a net energy metering agreement (NEM 1.0) credits at full retail rates.

30YR Energy Savings: “Performance” = Potential Induced Degradation (PID) is a potential induced performance degradation in crystalline solar Photo-Voltaic (PV) modules, caused by stray currents.

Assuming average nominal Price escalation rate (1972-2016) of 4%. Source: U.S. Energy Information Administration (EIA).

ROI: Solar investement – Return on Investment is equal to:  = ROI

System Size: Grid tied solar system measured by “Standard Test Conditions” (STC) are the industry standard for the conditions under which a solar panel are tested.

The direct current (DC) is the unidirectional flow of electric generated from solar cells.

Panels: Solar panel designed to absorb the sun’s rays for generating electricity.

Inverter: Solar Inverter converts the direct current – DC output of a solar panel into an alternating current – AC.

Annual Usage: Total energy (kWh-AC) the customer have been used in the last 12 months, based on customer input.

Annual Generate: Estimate solar energy (kWh) generation in solar real-world conditions at 1st YR. Refer to the California Energy Commission (CEC) Standards.

Covered by Solar: Excepted photostatic (PV) solar system energy (kWh) coverage.

Note: Some utilities will allow customers to size a solar system up to customer previous 12 months’ electrical usage.

Payback Period: Payback Period is the period required to cover the “Price” of the solar project.

Price: The total project cost will be charged by SOLAR PRICE DISCOVERY INC.

Note: (Permit, tax, labor and materials are included)

Federal Tax Credit (ITC): A tax credit is a dollar-for-dollar reduction in the amount of income tax you would otherwise owe (IRS Form 5659).  If the federal tax credit exceeds tax liability, the excess amount may be carried forward to the succeeding taxable year.

In case of utility rebate the “Federal Tax Credit” is subtracted from your system costs before we calculate your tax credit.

Estimate Rebate: Utility solar rebate are not guarantee and may be vary than indicated.

Net Price: Is the project “Price” deducted by 30% “Federal Tax Credit” (ITC) and “Estimate Rebate” (If any).

PV Solar Calculator – DICTIONARY

Online Estimator - DICTIONARY

Solar Panel: The solar panel absorb sun’s sun rays as a source of energy for generating electricity.

Photovoltaics (PV): is way of producing electrical power by converting solar radiation into direct current electricity using semiconductors.

Inverter: Inverter converts the electricity from your solar panels (DC, or direct current) into electricity that can be used in your house (AC, or alternating current).

String (Central) Inverter: Is a device used to modifies the direct current (DC) output of a photovoltaic (PV) solar panels into a utility frequency alternating current (AC)

Micro Inverter: Is a device used to converts direct current (DC) generated by a single solar module to alternating current (AC).

Optimizer: A power optimizer is a DC to DC converter device developed to maximize the energy harvest from solar photovoltaic.

DC Rating (kW STC): This is the calculated total DC STC (Standard Test Conditions) rated capacity of the PV modules and is measured by multiplying the STC module rating by the number of panels. This capability is utilized as an input to PV Watts to determine the performance of the system.

DC Rating (kW PTC): It is the measured total DC PTC (PVUSA Test Condition) rated capacity of the PV modules and is measured by multiplying the PTC module rating by the number of panels. This capability is used to calculate the CEC (California Energy Commission)-AC rating of the system.

CEC-AC Rating: This is the device of the PV module PTC rating, module and inverter efficiency. It can also be used in the solar system Rebates calculation.

AC (EFF): The AC-Efficiency of the PV solar System, combined with latitude and climate, measures the energy output of the system.

Geographic Location: Provide monthly average and annual average photovoltaic (PV) solar resource, averaged over surface cells of 0.1 degrees in both latitude and longitude.

Array Tilt (degrees): This is the proposed system tilt from horizontal. Flat (horizontal) systems have a 0º tilt.

Array Azimuth (degrees): This is the horizontal direction (“true” north-south) the suggested system is pointing; due South is 0º azimuth.

True South: True south is the direction towards the southern end of the axis about which the earth rotates, called the South Pole. (Magnetic south is the direction towards the south magnetic pole, some distance away from the south geographic pole).

Array Spreading: described the potion impact of solar array If a suggested system consists of PV arrays with different azimuths and tilts.

Degradation: Potential induced degradation is a possible induced performance degradation in photovoltaic modules.

Derate Factors: PVWATTS multiplies the nameplate DC power rating by a general DC to AC Derate factor to calculate the AC power rating at STC. The overall DC to AC Derate factor accounts for drawdowns from the DC nameplate power rating and is the mathematical product of the Derate factors for the components of the PV system.

Insolation: Solar Insolation is the number of electromagnetic energy (solar radiation) incident on the surface of the earth. Basically, that means how much sun energy is shining down on us.

Solar: The expected monthly kWh generation of the proposed system is shown along with the estimated production of one or two solar arrays at roof tilt.

Annual kWh: This is the approximated annual energy output of the proposed system. This value is reported for the sole reason for transparency of the calculator which is not a guarantee of future system performance.

Incentive: This is the total incentive for the proposed system (Tax Credit & Potential Rebates).

EPBB: Expected Performance-Based Buy down

ITC: Solar Investment Tax Credit.

Internal Rate on Return (IRR): Internal rate of return (IRR) is the interest rate at which the net present value of all the cash flows (either positive and negative) from a project or investment same zero. Internal rate of return is used to evaluate the attractiveness of a project or investment.

Payback Period: The length of time necessary for an investment to recover its preliminary outlay in terms of profits or savings.

Return on Investment (ROI): ROI is given as a percentage and is typically used for personal financial decisions, to examine a company’s profitability or to compare the efficiency of different investments. The return on investment formula is: ROI = (Net Profit / Cost of Investment) x 100.

Total return: Total return includes interest, capital gains, dividends and distributions realized over a given period.

Tax Deduction: Tax deduction is a reduction of income that can be taxed.

Tax Saving: Tax savings means that you pay a reduced amount of taxes, either because an investment earnings.

APR: An annual percentage rate (APR) is the annual rate that is incurred for borrowing (or created by investing), expressed as a single percentage amount that provides the true yearly cost of funds over the term of a loan. This consists of every fees or additional costs linked to the transaction.

After Tax APR: The effective interest rate after their potential tax deductible of the financing is considered.

Moving Average definition: Moving average that is determined by adding the closing price of the surety for several time periods and then dividing this total by the number of time periods.

Capitalized Interest: The interest of a loan occurred before 1st payment.

Net metering: Net energy metering, or “NEM”, is a special billing agreement that provides credit to customers with solar PV systems for the full retail value of the electricity their system generates.

Escalation Rate: The Energy Escalation Rate Calculator (EERC) computes an average annual escalation rate for a specified period, that can be used as an escalation rate for contract payments in energy power savings performance contracts.

Nominal Values: Nominal is an unadjusted rate and does not create adjustments to reflect factors such as seasonality or inflation.

Schedule: Customer classification associated with the Utility.

Baseline Allocation: Baseline Allocation is a set amount of kilowatt hours of energy (kWh) for basic services. Your specific Baseline Allocation is determined by three factors: your baseline region, the season (winter or summer), and whether your home’s source of energy is electricity only.

High Season: These are the months that define the summer period. Is used to determine changes of utility cost at summer time.

Low Season: These are the months that define the winter period. Is used to determine changes of utility cost at winter time.

Basic Charge: the costs associated with providing essential services, such as billing, equipment installation and maintenance, and meter reading.

DWR Bond: Bonds issued by the Department of Water Resources (DWR) to cover the cost of buying power for customers during the energy crisis are being repaid through a portion of your electric bill.

Property Assessed Clean Energy (PACE) is a way of financing energy efficiency improvements or renewables installations for home, business or industrial property owners. Depending on state legislation, PACE may be used to finance efficiency products such as solar systems. Some of the known programs in California are the Hero Program, California First, Ygrene.

Online Estimate – FAQ

Online Estimate - FAQ

How Do I Claim the Solar Tax Credit?

A tax credit is a dollar-for-dollar reduction in the total income tax you may otherwise owe. Tax Credit option may be available for purchasing PV solar system excluded leasing. To apply for Federal Tax Credit (ITC) use Form 5695, Residential Energy Credits. For more information check this link:  HOMEOWNER’S GUIDE TOTHE FEDERAL INVESTMENT TAX CREDITFOR SOLAR PV.

What PACE PROGRAM are available in California state?

Property Assessed Clean Energy (PACE) is a means of financing energy efficiency upgrades or renewable energy installations for residential, commercial and industrial property owners. It is depending on state legislation, PACE can be used to finance water efficiency products, seismic retrofits, and hurricane preparedness measures. Source:

Some of the familiar PACE Program available in California are: Hero, CaliforniaFirst and YgreneWorks.

What solar system size do I need to my home?

This is common question and frequent web review complains. Unfortunately, there is big confusion and misleading by non-professional solar installers in the market. PV solar system is a financial investment and not a home improvement products. Without a designated PV solar system software, it is almost impossible to analyze your benefits of having solar.

There are few free tools online that can assist you with preliminary resource, such as PV Watt calculator published by the NATIONAL RENEWABLE ENERGY LABORATORY (NREL)

Does installation of PV solar system will increase my Property tax appreciation?

Property Tax Exclusion for Solar Energy Systems installation. Section 73 of the California Revenue and Taxation Code allows a property tax exclusion for certain types of solar energy systems installed between January 1, 1999, and December 31, 2024. Source: Database of State Incentives for Renewables & Efficiency (DESIRE). For more information check Guidelines for Active Solar Energy Systems New Construction Exclusion at California State Board of equalization.

What will be the effects of the Net Energy Metering 2.0 (NEM-1.0) V.s. NEM-2.0?

Typical Net Metering (NEM 1.0) consider full credit on exported energy from your solar system to the grid. By getting into the NEM 2.0 you get less than the full retail price of energy by the utility. Per the California Public Utilities Commission (CPUC), the current Net Energy Metering 1.0 programs will be closed to new customers on July 1, 2017 or earlier.

Here is where things get complicate, the new NEM-2 discount solar energy exports by the amount of Non-Bypassable charges (NBC’s) for a specific rate schedule. The NBC’s charges are the utility costs of programs low-income assistance customers, energy efficiency, and nuclear decommissioning of shut down plants, etc. As for today, should not pay for non-By-passable charges by the end of the 12 months NEM cycle.  The discount is calculated by multiplying the energy (kWh) exports by the price difference of the “retail and export rate of the utility.

To learn more about the NEM-2, check your utility here: Southern California Edison (SCE), Sempra Energy Utility, Pacific Gas & Electric Co electric.

What type of Solar Panel do you suggest?

(Monocrystalline or Polycrystalline silicon panels. Hint: Polycrystalline are cheaper and absorb less sunlight)

What type of testing method does PV Solar Panel rated?

(Standard Test Conditions – STC, Performance Test Conditions – PTC, California Energy Commission – CEC)

What is Solar Panel Degradation?

(Solar system will lose partial of the production capability during the years. Normally they will lose up to 3% within the first two years, and 0.4% to 1% every year. Make sure your PV solar installer took it into consideration in your saving analysis.

What is the effect of My Roof Tilt, Azimuth and shading on my PV Solar Output?

Azimuth and Roof Tilt (Slope) can affect your system production up to 40% from suggested System Size in kWh-DC

Which type of data are you using to calculate my Solar Irradiation?

A typical meteorological year (TMY) is a collation of selected weather data for a specific location, generated from a data bank much longer than a year in duration and it’s the official method used by National Renewable Energy Laboratory -NREL. Make sure your solar installer does the right PV solar system performance based on the closet meteorology station to your property.

Will my PV Solar system cover 100% of my electric bill?

No, your utility provider may charge some fixed monthly fee like “Minimum Monthly Charge” and/or “Basic Charge”. Make sure your solar installer provides you transparent saving analysis.

What is my real utility historical escalation rate?

Different utilities have different rates, the average US nominal escalation rate in the last 30 YRs was 4%.

What is my local Baseline Region?

(Your Baseline Region is defining the amount of kWh usage in each Utility Tiers and might change between seasons. It is significantly effective on your potential saving analysis)

Can I claim for Tax Deductions on Full Payments paid together with my property Tax (Common in use PACE PROGRAMS)?

No, for more information, check IRS Publication 17, section 22 & IRS Rev Rul. 79-201

Serving locations

Serving locations

Acton, Agoura Hills, Alhambra, Altadena, Arcadia, Artesia, Azusa, Baldwin Park, Bell, Bell Gardens, Bellflower, Beverly Hills, Burbank, Calabasas, Canoga Park, Canyon Country, Carson, Castaic, Cerritos,, Chatsworth, City Of Industry, Claremont, Compton, Covina, Culver City, Diamond Bar, Downey, Duarte, El Monte, El Segundo, Encino, Gardena, Glendale, Glendora, Granada Hills, Hacienda Heights, Harbor City, Hawaiian Gardens, Hawthorne, Hermosa Beach, Huntington Park, Inglewood, Inland Empire, La Canada Flintridge, La Crescenta, La Mirada, La Puente, La Verne, Lake, Hughes, Lakewood, Lancaster, Lawndale, Littlerock, Llano, Lomita, Long Beach, Los Angeles, Lynwood, Malibu, Manhattan Beach, Marina Del Rey, Montrose, Orange County, Palmdale, Paramount, Pasadena, Reseda, San Pedro, Santa Clarita, Santa Fe Springs, Santa Monica, Sherman Oaks, Sierra Madre, Signal Hill, South El Monte, South Gate, South Pasadena, Stevenson Ranch, Studio City, Sun Valley, Sunland, Sylmar, Tarzana, Temple City, Toluca Lake, Topanga, Torrance, Tujunga, Universal City, Valencia, Valley Village, Valyermo, Van Nuys, Venice, Verdugo City, Victorville, Walnut, West Covina, West Hills, West Hollywood, Woodland Hills.