Google Solar Calculator

Solar Panel Potential & Savings Calculator

Use this calculator to estimate the potential solar system size needed for your home, its approximate cost, and the potential savings you could achieve by going solar. This tool helps you understand the basic economics of a solar investment based on your electricity consumption and local sunlight conditions.

function calculateSolar() { var monthlyElectricityBill = parseFloat(document.getElementById('monthlyElectricityBill').value); var electricityCostPerKWH = parseFloat(document.getElementById('electricityCostPerKWH').value); var avgDailySunlightHours = parseFloat(document.getElementById('avgDailySunlightHours').value); var panelWattage = parseFloat(document.getElementById('panelWattage').value); var systemCostPerWatt = parseFloat(document.getElementById('systemCostPerWatt').value); var systemLifespan = parseFloat(document.getElementById('systemLifespan').value); var resultDiv = document.getElementById('result'); resultDiv.innerHTML = "; // Clear previous results // Input validation if (isNaN(monthlyElectricityBill) || monthlyElectricityBill < 0 || isNaN(electricityCostPerKWH) || electricityCostPerKWH <= 0 || isNaN(avgDailySunlightHours) || avgDailySunlightHours <= 0 || isNaN(panelWattage) || panelWattage <= 0 || isNaN(systemCostPerWatt) || systemCostPerWatt <= 0 || isNaN(systemLifespan) || systemLifespan <= 0) { resultDiv.innerHTML = 'Please enter valid positive numbers for all fields.'; return; } // 1. Calculate Annual kWh Consumption var annualKWHConsumption = (monthlyElectricityBill / electricityCostPerKWH) * 12; // 2. Calculate Daily kWh Consumption var dailyKWHConsumption = annualKWHConsumption / 365; // 3. Calculate Required System Size (in kW) // System size (kW) = Daily kWh needed / Peak Sunlight Hours var requiredSystemSizeKW = dailyKWHConsumption / avgDailySunlightHours; // 4. Calculate Number of Panels // Convert required system size to Watts for panel calculation var requiredSystemSizeWatts = requiredSystemSizeKW * 1000; var numPanels = Math.ceil(requiredSystemSizeWatts / panelWattage); // 5. Calculate Total System Cost var totalSystemCost = requiredSystemSizeWatts * systemCostPerWatt; // 6. Calculate Annual Savings var annualSavings = annualKWHConsumption * electricityCostPerKWH; // 7. Calculate Total Savings Over Lifespan var totalSavingsLifespan = annualSavings * systemLifespan; // 8. Calculate Payback Period var paybackPeriod = totalSystemCost / annualSavings; resultDiv.innerHTML = '

Estimated Solar Potential:

' + 'Estimated Annual Electricity Consumption: ' + annualKWHConsumption.toFixed(0) + ' kWh' + 'Required System Size: ' + requiredSystemSizeKW.toFixed(2) + ' kW' + 'Estimated Number of Panels: ' + numPanels + ' panels (based on ' + panelWattage + 'W panels)' + 'Estimated Total System Cost: $' + totalSystemCost.toFixed(2) + " + '

Estimated Financial Benefits:

' + 'Estimated Annual Electricity Savings: $' + annualSavings.toFixed(2) + " + 'Estimated Total Savings Over ' + systemLifespan + ' Years: $' + totalSavingsLifespan.toFixed(2) + " + 'Estimated Payback Period: ' + paybackPeriod.toFixed(1) + ' years' + 'Note: These are estimates. Actual costs and savings may vary based on specific equipment, installation, incentives, and future electricity rates. Consult with a professional solar installer for an accurate quote.'; } .solar-calculator-container { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f9f9f9; padding: 25px; border-radius: 10px; box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1); max-width: 700px; margin: 20px auto; border: 1px solid #e0e0e0; } .solar-calculator-container h2 { color: #2c3e50; text-align: center; margin-bottom: 20px; font-size: 26px; } .solar-calculator-container h3 { color: #34495e; margin-top: 25px; margin-bottom: 15px; font-size: 20px; border-bottom: 1px solid #eee; padding-bottom: 5px; } .solar-calculator-container p { color: #555; line-height: 1.6; margin-bottom: 10px; } .calculator-form .form-group { margin-bottom: 18px; display: flex; flex-direction: column; } .calculator-form label { font-weight: bold; margin-bottom: 8px; color: #333; font-size: 15px; } .calculator-form input[type="number"] { width: 100%; padding: 12px; border: 1px solid #ccc; border-radius: 6px; box-sizing: border-box; font-size: 16px; transition: border-color 0.3s ease; } .calculator-form input[type="number"]:focus { border-color: #007bff; outline: none; box-shadow: 0 0 5px rgba(0, 123, 255, 0.2); } .calculator-form .description { font-size: 13px; color: #777; margin-top: 5px; margin-bottom: 0; } .calculator-form button { background-color: #28a745; color: white; padding: 14px 25px; border: none; border-radius: 6px; cursor: pointer; font-size: 18px; font-weight: bold; display: block; width: 100%; margin-top: 25px; transition: background-color 0.3s ease, transform 0.2s ease; } .calculator-form button:hover { background-color: #218838; transform: translateY(-2px); } .calculator-form button:active { transform: translateY(0); } .calculator-result { background-color: #e9f7ef; border: 1px solid #d4edda; border-radius: 8px; padding: 20px; margin-top: 30px; color: #155724; } .calculator-result p { margin-bottom: 8px; font-size: 16px; } .calculator-result p strong { color: #0f5132; } .calculator-result .disclaimer { font-size: 13px; color: #6c757d; margin-top: 20px; border-top: 1px dashed #c3e6cb; padding-top: 10px; }

Understanding Your Solar Potential

Going solar is a significant investment that can lead to substantial long-term savings and environmental benefits. This calculator provides a simplified estimate of what you might expect. Here's a breakdown of the factors involved:

How the Calculator Works

Our Solar Panel Potential & Savings Calculator uses a few key pieces of information about your energy consumption and local conditions to estimate the size of the solar system you'd need and its potential financial impact.

• Average Monthly Electricity Bill: This is the starting point. By knowing your typical bill, and your electricity cost per kWh, we can estimate your total annual electricity consumption in kilowatt-hours (kWh).
• Average Electricity Cost per kWh: Found on your utility bill, this helps convert your bill amount into actual energy usage and calculate your potential savings.
• Average Daily Peak Sunlight Hours: Not all sunlight is equal. "Peak sunlight hours" refer to the equivalent number of hours per day when solar irradiance averages 1,000 watts per square meter. This is crucial for determining how much energy your panels can produce daily.
• Typical Solar Panel Wattage: This is the power output of an individual solar panel. Higher wattage panels mean fewer panels are needed for the same system size.
• Estimated System Cost per Watt: This figure includes the cost of panels, inverters, mounting hardware, labor, permitting, and other installation expenses, averaged out per watt of system capacity.
• System Lifespan: Solar panels are durable and typically come with performance warranties of 20-25 years, though they can last much longer. This helps calculate total long-term savings.

Key Outputs Explained

• Estimated Annual Electricity Consumption: The total amount of electricity your home uses in a year, measured in kWh.
• Required System Size (kW): The total power output capacity your solar array needs to generate enough electricity to cover your consumption.
• Estimated Number of Panels: Based on the required system size and the wattage of individual panels, this tells you approximately how many panels you'd need.
• Estimated Total System Cost: The approximate upfront cost of purchasing and installing your solar system before any incentives or tax credits.
• Estimated Annual Electricity Savings: The amount of money you could save on your electricity bill each year by generating your own power.
• Estimated Total Savings Over Lifespan: The cumulative savings you could achieve over the entire operational life of your solar system.
• Estimated Payback Period: The number of years it would take for your electricity savings to equal the initial cost of your solar system.

Factors Not Included (But Important!)

This calculator provides a good starting point, but a real-world solar installation involves more variables:

• Local Incentives & Tax Credits: Federal, state, and local incentives (like the federal solar tax credit) can significantly reduce your net system cost and improve your payback period.
• Roof Characteristics: Roof size, angle, shading from trees or other buildings, and material all impact panel placement and efficiency.
• Energy Price Escalation: Future increases in electricity rates can make solar even more financially attractive over time.
• System Degradation: Solar panels slowly lose a small amount of efficiency each year (typically 0.5% to 1%).
• Financing Costs: If you finance your solar system, interest payments will affect your overall costs and savings.
• Maintenance: While minimal, occasional cleaning or repairs might be needed.

For a precise assessment and quote, always consult with multiple reputable local solar installers. They can evaluate your specific property, discuss available incentives, and design a system tailored to your needs.