To calculate solar savings: Monthly savings = Monthly kWh generated x Electricity rate. A 3kW system generates 300-390 kWh/month in Sri Lanka. At 25 rupees/kWh average, monthly savings = 7,500-9,750 rupees. Payback period = System cost / Monthly savings. A 750,000 rupee system with 8,000/month savings has a payback of ~7.8 years.
📂 Finance
☀️ Solar Panel Calculator
Calculate solar panel savings, payback period, and return on investment for your home or business. Enter your electricity bill and system size to see if solar makes financial sense.
✏️ Enter Your Values
✨ Your Result
🦉Owl's Explanation
☀️
Fill in the values above and click Calculate ✨
✅ Trusted Tool
The 365tool.net Solar Panel Calculator uses average generation data for each region. Actual generation varies significantly by panel orientation, shading, and local conditions. Always consult a licensed solar installer for site-specific analysis. Free for homeowners. No sign-up needed.
🤔 How Does This Work?
The Solar Panel Calculator estimates financial returns:
Monthly generation = System kW x Country average kWh/kW/month
Average rate = Monthly bill / Monthly kWh
Monthly savings = Generation (up to your usage) x Rate
Payback = System cost / Monthly savings
25-year total = Monthly savings x 300 months
❓ Frequently Asked Questions
How much does solar cost in Sri Lanka?▼
A 1kW system costs approximately 200,000-300,000 rupees installed. A 3kW system (suitable for most homes) costs 600,000-900,000 rupees. Prices vary by brand quality and installer. Always get at least 3 quotes. Choose CEB-approved systems and licensed installers for warranty and grid connection support.
What is net metering in Sri Lanka?▼
Net metering allows you to sell excess solar electricity back to the CEB grid. When panels generate more than you use during the day, excess flows to the grid and you get bill credits. This makes solar financially viable even if you are not home during peak generation hours. Check current CEB net metering policy as terms update periodically.
How long do solar panels last?▼
Quality solar panels come with 25-year performance warranties and typically last 30+ years. Inverters usually need replacement after 10-15 years. Panel output degrades very slowly — about 0.5-1% per year. After 25 years, a quality panel still produces 75-80% of its original output. The long lifespan makes the economics very favourable.
Is my roof suitable for solar?▼
Ideal: south-facing roof (in Sri Lanka, flat or south-facing), minimal shading from trees or buildings, structurally sound. Problematic: roof facing north (in Sri Lanka), heavy shading especially in morning or afternoon, old roof needing replacement soon (remove panels for re-roofing is expensive). A site assessment by a solar installer is recommended before purchasing.
How do I maximise solar ROI?▼
Use high-electricity appliances (washing machine, dishwasher) during daylight hours when solar production is highest. This maximises self-consumption and reduces grid import. Install a timer on your water heater to run during peak solar hours. Consider a battery storage system for evening use of solar energy generated during the day.
A 1kW system costs approximately 200,000-300,000 rupees installed. A 3kW system (suitable for most homes) costs 600,000-900,000 rupees. Prices vary by brand quality and installer. Always get at least 3 quotes. Choose CEB-approved systems and licensed installers for warranty and grid connection support.
What is net metering in Sri Lanka?▼
Net metering allows you to sell excess solar electricity back to the CEB grid. When panels generate more than you use during the day, excess flows to the grid and you get bill credits. This makes solar financially viable even if you are not home during peak generation hours. Check current CEB net metering policy as terms update periodically.
How long do solar panels last?▼
Quality solar panels come with 25-year performance warranties and typically last 30+ years. Inverters usually need replacement after 10-15 years. Panel output degrades very slowly — about 0.5-1% per year. After 25 years, a quality panel still produces 75-80% of its original output. The long lifespan makes the economics very favourable.
Is my roof suitable for solar?▼
Ideal: south-facing roof (in Sri Lanka, flat or south-facing), minimal shading from trees or buildings, structurally sound. Problematic: roof facing north (in Sri Lanka), heavy shading especially in morning or afternoon, old roof needing replacement soon (remove panels for re-roofing is expensive). A site assessment by a solar installer is recommended before purchasing.
How do I maximise solar ROI?▼
Use high-electricity appliances (washing machine, dishwasher) during daylight hours when solar production is highest. This maximises self-consumption and reduces grid import. Install a timer on your water heater to run during peak solar hours. Consider a battery storage system for evening use of solar energy generated during the day.