# Solar Panel Sizing Calculator — Ireland

> Translate a site-specific annual energy target into a rounded panel count and a transparent material-cost scenario. EUR planning view; stated limitations apply.

Page: https://askcalculators.com/ie/solar-sizing/
Definition: https://askcalculators.com/ie/solar-sizing/definition.json
JSON Schema: https://askcalculators.com/ie/solar-sizing/schema.json
Version: 20.16.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/ie/solar-sizing/?unitSystem=metric&annualUse=10000&offset=80&specificYield=1200&panelWatts=420&panelArea=2&layoutAllowance=20&unitRate=0&laborCost=0&deliveryCost=0&otherCost=0&costMultiplier=1&spreadPercent=15&taxRate=0

## Inputs
- unitSystem: Measurement system; type=select; optional; default=metric; values=imperial|metric
- annualUse: Annual electricity use, kWh; type=number; required; default=10000; min=1; max=100000000
- offset: Target annual generation / use; type=percent; required; default=80; min=0; max=300
- specificYield: Site-specific annual yield, kWh per kW; type=number; required; default=1200; min=100; max=3000
- panelWatts: Panel nameplate output, W; type=number; required; default=420; min=50; max=1000
- panelArea: Area of one panel; type=number; required; default=2; min=0.1; max=10
- layoutAllowance: Roof-layout allowance beyond panel area; type=percent; required; default=20; min=0; max=100
- unitRate: Material price per panel; type=money; required; default=0; min=0; max=1000000000000
- laborCost: Total labor allowance; type=money; required; default=0; min=0; max=1000000000000
- deliveryCost: Delivery allowance; type=money; required; default=0; min=0; max=1000000000000
- otherCost: Other fixed costs; type=money; required; default=0; min=0; max=1000000000000
- costMultiplier: Material/labor multiplier; type=number; required; default=1; min=0.1; max=10
- spreadPercent: Low/high sensitivity around the entered total; type=percent; required; default=15; min=0; max=100
- taxRate: Explicit tax allowance; type=percent; required; default=0; min=0; max=100

## Outputs
- panels: Whole panels to order; format=number
- installedKw: Installed nameplate capacity, kW; format=number
- generation: Modeled annual generation, kWh; format=number
- roofArea: Roof area allowance; format=number
- materialCost: Material cost; format=currency
- laborCost: Labor allowance; format=currency
- deliveryCost: Delivery allowance; format=currency
- otherCost: Other specified costs; format=currency
- tax: Entered tax allowance; format=currency
- low: Low cost scenario; format=currency
- mid: Middle cost scenario; format=currency; primary
- high: High cost scenario; format=currency

## Formula
panels = ceiling(annual use × offset ÷ yield × 1,000 ÷ panel watts).

Inputs are converted to canonical units before evaluating this stated formula.

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.

Notice: Illustrative defaults are not local quotes or verified legal rules. Dated reference components and user-entered assumptions are explicitly distinguished. Professional review is pending.