Solar
Savings
Calculator
Estimate your monthly & yearly savings from solar energy in Pakistan
Solar Savings Calculator
⚡Your Electricity Usage
Used for accurate solar irradiance data.
Expected yearly electricity price increase. Default 5%.
🏠 Roof Specifications
Shadow-free area. ~100 sq ft = 1 kW of solar.
South-facing gives maximum output in Pakistan.
📊 System Overview
System Size
—
kW recommended
System Cost
—
PKR total
Annual Generation
—
kWh / year
Bill Offset
—
% of bill covered
💰 Monthly Savings
—
PKR / month
📅 Yearly Savings
—
PKR / year
⏱ Payback Period
—
years to break even
CO₂ Avoided
—
kg / year
Panel Efficiency (adj.)
—
% adjusted for shading
25-Year Total Savings
—
PKR (with escalation)
📉 Monthly Bill: Before vs After Solar
📋 25-Year Savings Projection
📐 Calculation Assumptions
Panel efficiency20%
System derate factor0.85
Performance ratio0.80
CO₂ reduction factor0.7 kg/kWh
Roof → kW conversion100 sq ft = 1 kW
Default system costRs 150,000/kW
* System size = min(monthly kWh ÷ sunHrs ÷ 30 ÷ PR, roof area ÷ 100). Annual generation = systemKW × sunHrs × 365 × PR × derate × orientation factor × (1 − shading%). Monthly savings = min(gen ÷ 12 × tariff, monthly bill). CO₂ = generation × 0.7. Payback = system cost ÷ annual savings. All values are indicative estimates only.
