Mortgage Rate Calculator with Down Payment

Solar Panel Savings & Payback Calculator

Your Solar Analysis

Net System Cost:

Annual Savings:

Estimated Payback Period:

25-Year Total Savings:

function calculateSolarSavings() { var size = parseFloat(document.getElementById('systemSize').value); var hours = parseFloat(document.getElementById('sunHours').value); var rate = parseFloat(document.getElementById('elecRate').value); var cost = parseFloat(document.getElementById('installCost').value); var credit = parseFloat(document.getElementById('taxCredit').value); if (isNaN(size) || isNaN(hours) || isNaN(rate) || isNaN(cost) || isNaN(credit)) { alert("Please fill in all fields with valid numbers."); return; } // Calculations // Efficiency factor (degradation/inverter loss) is typically ~78% var dailyProduction = size * hours * 0.78; var yearlyProduction = dailyProduction * 365; var annualSavings = yearlyProduction * rate; var netCost = cost – (cost * (credit / 100)); var paybackYears = netCost / annualSavings; var twentyFiveYearSavings = (annualSavings * 25) – netCost; // Update DOM document.getElementById('netCostDisplay').innerHTML = "$" + netCost.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('annualSavingsDisplay').innerHTML = "$" + annualSavings.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('paybackDisplay').innerHTML = paybackYears.toFixed(1) + " Years"; document.getElementById('lifetimeSavingsDisplay').innerHTML = "$" + twentyFiveYearSavings.toLocaleString(undefined, {minimumFractionDigits: 0, maximumFractionDigits: 0}); document.getElementById('solarResult').style.display = 'block'; }

How Much Can You Really Save with Solar?

Switching to solar energy is one of the most effective ways to reduce your monthly utility bills and increase your home's value. However, the financial benefit depends on several key variables. Our Solar Panel Savings Calculator helps you estimate the return on investment (ROI) by analyzing your specific location and energy costs.

Key Factors in the Calculation

• System Size (kW): Most residential systems range from 5kW to 10kW. A larger system produces more power but costs more upfront.
• Peak Sun Hours: This isn't just "daylight." It's the equivalent intensity of full sun. States like Arizona average 5.5+ hours, while New York might average 3.5 to 4 hours.
• The Federal Solar Tax Credit (ITC): As of 2023, the federal government offers a 30% tax credit on the total cost of installation, significantly shortening the payback period.
• Electricity Rates: The more your utility company charges per kWh, the more you save by generating your own power.

Example Scenario

If you install a 6 kW system in a region with 4.5 sun hours per day, your system will produce approximately 7,680 kWh per year. At a utility rate of $0.16 per kWh, you save roughly $1,228 annually. If the system cost $18,000, after the 30% tax credit ($5,400), your net cost is $12,600. Your payback period would be roughly 10.2 years.

Long-term ROI

Most solar panels are warrantied for 25 years. After your system "pays for itself" (the payback period), the electricity generated for the remainder of the system's life is essentially free. With rising utility costs, your actual savings over 25 years often exceed $30,000 to $50,000 depending on your local energy market.