Estimate your potential savings and payback period for switching to solar energy.
Low (3.5h – e.g. Seattle)
Average (4.5h – e.g. St. Louis)
High (5.5h – e.g. Phoenix)
Your Estimated Results
Net System Cost$0
Annual Savings$0
Payback Period0 Years
25-Year Net Profit$0
Is Solar Energy a Good Investment for You?
Switching to solar power is more than just an environmental choice; it's a significant financial decision. By generating your own electricity, you can drastically reduce or even eliminate your monthly utility bills. With the Federal Solar Tax Credit (ITC) currently offering a significant reduction in upfront costs, there has never been a better time to calculate your ROI.
How the Calculator Works
Our Solar Savings Calculator uses several key metrics to provide an accurate estimate:
Annual Energy Production: We estimate your system's output by multiplying the system size (kW) by your regional peak sun hours and factoring in a standard 15% system inefficiency loss.
Net System Cost: This is the total installation price minus your local and federal tax incentives.
Payback Period: The amount of time it takes for your cumulative electricity savings to equal the initial net cost of the system.
Factors Affecting Your Solar Savings
Several variables can influence how much you save over the life of your panels:
Roof Orientation: South-facing roofs in the Northern Hemisphere typically generate the most power.
Local Electricity Rates: The higher your current utility rates, the faster your solar panels will pay for themselves.
Net Metering: Some states allow you to sell excess energy back to the grid at retail rates, which speeds up your ROI.
Panel Degradation: Most panels are warrantied for 25 years but lose about 0.5% efficiency each year.
Example Calculation
Imagine a homeowner in a sunny region with a $150 monthly bill. If they install a 6kW system costing $18,000 before a 30% tax credit, their net cost is $12,600. If the system produces $1,600 worth of electricity annually, the payback period would be roughly 7.8 years. Over 25 years, even accounting for minor maintenance, the total profit could exceed $30,000.
function calculateSolarROI() {
// Inputs
var monthlyBill = parseFloat(document.getElementById('monthlyBill').value);
var rate = parseFloat(document.getElementById('elecRate').value);
var size = parseFloat(document.getElementById('systemSize').value);
var cost = parseFloat(document.getElementById('installCost').value);
var credit = parseFloat(document.getElementById('taxCredit').value);
var sunHours = parseFloat(document.getElementById('sunHours').value);
// Validate
if (isNaN(monthlyBill) || isNaN(rate) || isNaN(size) || isNaN(cost) || isNaN(credit)) {
alert('Please fill in all fields with valid numbers.');
return;
}
// Calculations
var netCost = cost * (1 – (credit / 100));
// Annual Production (kW * hours * 365 days * 0.85 efficiency factor)
var annualKwhProduced = size * sunHours * 365 * 0.85;
// Annual Energy Usage
var annualKwhUsed = (monthlyBill / rate) * 12;
// Annual Savings (Can't save more than you use, generally)
var savingsKwh = Math.min(annualKwhProduced, annualKwhUsed);
var annualSavings = savingsKwh * rate;
// Payback Period
var paybackYears = netCost / annualSavings;
// 25 Year Profit (Total savings over 25 years – net cost)
// Factoring 2% electricity price inflation and 0.5% panel degradation
var total25YearSavings = 0;
var currentYearSavings = annualSavings;
for (var i = 1; i <= 25; i++) {
total25YearSavings += currentYearSavings;
currentYearSavings = currentYearSavings * 1.02 * 0.995;
}
var netProfit = total25YearSavings – netCost;
// Display Results
document.getElementById('netCostDisplay').innerText = '$' + netCost.toLocaleString(undefined, {minimumFractionDigits: 0, maximumFractionDigits: 0});
document.getElementById('annualSavingsDisplay').innerText = '$' + annualSavings.toLocaleString(undefined, {minimumFractionDigits: 0, maximumFractionDigits: 0});
document.getElementById('paybackDisplay').innerText = paybackYears.toFixed(1) + ' Years';
document.getElementById('profitDisplay').innerText = '$' + netProfit.toLocaleString(undefined, {minimumFractionDigits: 0, maximumFractionDigits: 0});
document.getElementById('solarResults').style.display = 'block';
// Smooth scroll to results
document.getElementById('solarResults').scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}