SUN RAY SOLUTIONS · SOLAR TOOLS

Solar panel upgrade calculator

Compare your current panels with a higher-wattage design. See average production and the possible change in annual electricity value.

Editable example · No signup · Annual averages, not live production

Estimated annual value change—View comparison

1. Your current system

Current panel countUse the whole system being compared.Current watts per panelCheck the original proposal or equipment records.

Current production basis

Current annual yield (kWh per kW)Illustrative net AC yield; already includes operating losses. Edit for your roof.

Comparing an upgrade with a hail repair? Use the expected repaired-system production as your baseline.

2. Your proposed system

Proposed panel countThe same count may not fit; confirm the new layout.Proposed watts per panelA comparison input, not a product recommendation.

Inverter plan

Proposed annual yield (kWh per kW)Example only. For a modeled design, divide annual AC kWh by DC system kW; include clipping in that model.

3. Electricity use, rates & optional cost

Starting values are examples, not your tariff. Use avoided variable import charges and your effective export credit after caps.

Home electricity use (kWh/year)Total household use, not grid imports alone.Avoided import price (¢/kWh)Exclude fixed monthly charges.Effective export credit (¢/kWh)Use 0 if exports are unpaid.Current solar used at home (%)Proposed solar used at home (%)Optional out-of-pocket upgrade cost ($)For a repair-versus-upgrade decision, use only the extra upgrade cost and a repaired-system baseline. Leave blank for no payback estimate.

ESTIMATED ANNUAL VALUE CHANGE

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Bill value before project cost. Change the examples to match your home.

Current DC size—

Proposed DC size—

Current vs. proposed production
Average	Current	Proposed
kWh / year	—	—
kWh / month	—	—
kWh / day	—	—
Value / year	—	—

Additional energy / year: —
Average value change / month: —
Simple payback: Enter a cost

Assumes a compatible design. Roof fit and equipment limits need review.

Enable JavaScript to edit the calculator. Example: 20 × 250 W = 5 kW; 20 × 450 W = 9 kW. At an illustrative 1,450 kWh/kW/year, production is 7,250 vs. 13,050 kWh/year. This is not a forecast for your home.

What these numbers mean

System size: panel count × watts ÷ 1,000 = rated DC kW. Estimated annual production: DC kW × net annual AC yield. For measured current production, we use your entered total without applying a second loss factor.

Monthly and daily averages: annual kWh ÷ 12 and ÷ 365. Actual months and days differ with seasons and weather. This tool does not estimate today’s output or diagnose hail damage.

Electricity value: on-site kWh × avoided import rate + exported kWh × effective export rate. On-site kWh is the smaller of annual home use and production × your selected on-site share. Exported kWh is the remainder. Annual totals cannot determine actual self-consumption; compare the shares with interval data. Battery losses and time-of-use pricing need separate modeling.

Additional value: proposed annual value minus current annual value. This may be small or negative even when panel wattage rises. It is a gross first-year bill-value comparison, not profit or a guaranteed bill reduction.

Simple payback: entered cost ÷ positive additional annual value. This holds first-year performance and rates constant and excludes financing, future maintenance, degradation, rate changes, and discounting. No tax credit or insurance payment is assumed.

The default yield of 1,450 kWh/kW/year is an illustrative input, not a surveyed DFW average. Replace it with a site-specific estimate from PVWatts or your designer, including orientation, shading, inverter limits, and losses. This calculator does not call PVWatts or verify electrical compatibility. It suppresses proposed production and savings when you select an unreviewed existing inverter.

Put the comparison in context

SUN RAY SOLUTIONS · DFW

Review the numbers with your equipment.

Use the comparison button to include these inputs in your request. We will review the proposed design, equipment compatibility, and written project cost.

Call (945) 444-1941 or text ground-level photos. Serving Dallas–Fort Worth and communities up to approximately two hours beyond DFW. No travel fee.

Name *Phone *City or ZIP code *Email (optional)Service needed *

Add project details (optional)

Share what you know. We can work through the rest with you.

Panel count, if knownProposed work dateEquipment brand/model, if knownMonthly electricity use or bill, if knownHow did you hear about us? (optional)Anything else we should know?

We use your details to respond to this request. Please leave out account passwords and payment information.

Text project photos with your name and city to (945) 444-1941.

Sources & further reading

Reviewed September 27, 2026. These independent resources explain the underlying issues; they do not endorse Sun Ray Solutions or guarantee a project result.