Solar Panel Output Chart

Use this chart after the solar calculator result to record panel wattage, panel count, sun-hour assumptions, system losses, daily production, average monthly production, first-year annual production, degradation, and estimated usage coverage.

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Quick reference table

A solar panel output chart keeps panel capacity, sun-hour assumptions, system losses, degradation, and kWh production in one worksheet before comparing system size, battery needs, or payback.

Solar panel output worksheet

Solar panel output worksheet
Item	Record from calculator	Follow-up
Array size	Panel watts and panel count	Confirm roof, ground, or rack layout
Solar resource	Peak sun hours	Review location and seasonal basis
Losses	System losses and performance factor	Check shade, orientation, inverter, wiring, soiling, availability, and temperature
Production	Daily, average monthly, first-year annual, and year-25 kWh	Compare with usage, modeled production, installer proposal, and interconnection requirements

Solar output site-context review

Solar output site-context review
Site item	Record on worksheet	Why it changes production
Orientation and tilt	Azimuth, tilt, roof or rack note	Array geometry changes the useful sun-hour basis
Shade window	Tree, chimney, parapet, or seasonal shade	Shade can reduce output even when panel count is unchanged
Inverter path	Inverter rating, clipping note, AC output basis	DC production and AC delivery are not the same value
Production model	User-entered sun hours, losses, and degradation	Production quality depends on weather data and site assumptions
Bill comparison	Usage period, export credit rule, self-use note	Production becomes savings only after rate and usage review

Formula basis

Daily solar kWh = panel watts x panel count x peak sun hours x performance ratio / 1000. Year-25 kWh = first-year kWh x (1 - annual degradation) ^ 24.

Panel watts are the module rating used by the calculator.
Panel count is the number of modules included in the estimate.
Peak sun hours are the location and season assumption entered for production.
System losses set the performance factor used in the production estimate.
Annual degradation estimates future-year output from the first-year value.

Worked examples

Residential output recordRecord 420 W modules, panel count, peak sun hours, system losses, daily kWh, average monthly kWh, first-year annual kWh, degradation, and whether the next step is battery or payback review.

Shaded roof output estimateDocument panel watts, string location, shade period, orientation, inverter clipping note, seasonal sun hours, and monthly kWh before moving to payback or battery sizing.

Assumptions. Balanced load and line-to-line voltage assumptions behind this chart.

Solar production changes with location, weather, orientation, shade, temperature, equipment losses, and utility interconnection rules.
This chart records production assumptions; use location-specific modeling when the project needs monthly output by site.
The chart supports an early production estimate and does not replace a site survey or engineered PV design.

Code and standard notes. Planning limits that should be checked before final equipment selection.

Use this chart as a preliminary reference; verify site conditions, interconnection requirements, manufacturer data, adopted NEC PV installation requirements, AHJ expectations, and qualified project review before design or procurement.

How to use this chart

1Record array inputsDocument module watts, panel count, sun hours, losses, production factor, and degradation before comparing production.

2Attach site contextList orientation, tilt, shade, roof area, inverter path, and seasonal assumptions.

3Choose the next stepUse output results to move to battery sizing, system sizing, or payback review.

Worksheet checklist. Record source basis, review gaps, and assumptions before using the chart result.

Capture capacityRecord module wattage, panel count, array kW, and inverter basis.
Capture productionWrite daily, average monthly, first-year annual, year-25 kWh, production factor, and estimated usage coverage.
Capture review itemsList shade, service-provider, roof, permitting, and manufacturer follow-up items.

Common mistakes to avoid. Review these before turning chart current into an equipment decision.

Treating one average sun-hour value as every season of production.
Treating a quick calculator result as a site-specific monthly production model.
Comparing production with bill savings without rate and export-credit context.
Ignoring shade, orientation, inverter clipping, or self-consumption when using the daily kWh result.

Frequently asked questions

These answers explain how to use the chart without turning a quick reference into a final design decision.

Why use peak sun hours?

Peak sun hours convert solar resource into a practical production estimate, but the value should match the location and season being studied.

Does output equal bill savings?

No. Bill savings also depend on rate structure, export credit, self-consumption, demand charges, and provider policy.