Estimate your potential savings by switching to solar energy.
Enter your address and current electricity usage.
Estimated Annual Savings
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Understanding Solar Energy Savings
Switching to solar energy is a significant investment that can lead to substantial long-term savings on your electricity bills. This calculator provides an estimate of your potential financial benefits based on key factors related to your home, your electricity consumption, and the proposed solar energy system.
How the Calculator Works:
The core of this calculator involves comparing your current electricity costs with the estimated cost of generating your own electricity using solar panels. The "solar calculator by address" aspect is a simplification; while an actual detailed analysis would consider precise roof orientation, shading, and local weather data specific to your address, this tool uses a generalized Estimated Annual Production Factor for your region.
Annual Electricity Usage (kWh): This is the total amount of electricity your household consumes in a year. You can usually find this on your past electricity bills.
Current Electricity Rate ($/kWh): This is the price you pay for each kilowatt-hour (kWh) of electricity from your utility provider. This rate can vary based on your plan and location.
Solar System Size (kW): This refers to the system's capacity to generate power, measured in kilowatts (kW). A larger system can generate more electricity.
Estimated Annual Production Factor (kWh/kWp): This crucial factor estimates how much energy a 1kW solar panel system will produce annually at your location. It accounts for average sunlight hours, panel efficiency, and typical weather patterns. A higher factor means more energy production per kW of installed capacity. For example, a factor of 1300 kWh/kWp means a 1kW system is expected to produce 1300 kWh of electricity per year. This is the most location-dependent variable.
Total Solar System Cost ($): This is the upfront cost of purchasing and installing the solar panel system. It's important to consider any available tax credits or incentives, which are not factored into this basic calculation but can significantly reduce the net cost.
The Calculation Logic:
Current Annual Electricity Cost: Current Annual Cost = Annual Electricity Usage (kWh) * Current Electricity Rate ($/kWh)
Estimated Annual Solar Energy Production: Annual Solar Production = Solar System Size (kW) * Estimated Annual Production Factor (kWh/kWp)
Estimated Value of Solar Energy Produced:
Assuming the solar energy produced offsets your grid electricity consumption at your current rate:
Value of Solar Energy = Annual Solar Production (kWh) * Current Electricity Rate ($/kWh)
Estimated Annual Savings:
This is the difference between what you would have paid for electricity and the value of the solar energy you produce.
Estimated Annual Savings = Current Annual Cost - Value of Solar Energy Note: This is a simplified calculation. In reality, net metering policies, time-of-use rates, and whether your system produces more than you consume can affect exact savings. This calculation assumes you consume all the solar energy you produce or are credited at your retail rate.
Simple Payback Period (Years):
This estimates how long it will take for the savings to equal the initial investment.
Simple Payback Period = Total Solar System Cost ($) / Estimated Annual Savings This is a "simple" payback and doesn't account for inflation, potential maintenance costs, or degradation of solar panels over time.
Use Cases:
This calculator is a valuable tool for homeowners and potential solar customers to:
Get a preliminary idea of the financial viability of installing solar panels.
Understand the key metrics that influence solar savings.
Compare different system sizes or electricity rates to see the potential impact on savings.
Initiate conversations with solar installers by having a baseline understanding of potential returns.
Disclaimer: This calculator provides an estimation only. Actual savings may vary based on precise location, system performance, utility rate structures, installation specifics, and changes in energy consumption. It is recommended to consult with a professional solar installer for a personalized assessment.
function calculateSolarSavings() {
var annualKwh = parseFloat(document.getElementById("annualKwh").value);
var currentRatePerKwh = parseFloat(document.getElementById("currentRatePerKwh").value);
var solarSystemSizeKw = parseFloat(document.getElementById("solarSystemSizeKw").value);
var annualProductionFactor = parseFloat(document.getElementById("annualProductionFactor").value);
var solarSystemCost = parseFloat(document.getElementById("solarSystemCost").value);
var address = document.getElementById("address").value; // Address is used for context, not calculation
var resultValueElement = document.getElementById("result-value");
var resultDetailsElement = document.getElementById("result-details");
// Clear previous results and error messages
resultValueElement.innerHTML = "–";
resultDetailsElement.innerHTML = "";
// Input validation
var inputsValid = true;
if (isNaN(annualKwh) || annualKwh <= 0) {
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter a valid Annual Electricity Usage (kWh).";
}
if (isNaN(currentRatePerKwh) || currentRatePerKwh <= 0) {
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter a valid Current Electricity Rate ($/kWh).";
}
if (isNaN(solarSystemSizeKw) || solarSystemSizeKw <= 0) {
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter a valid Solar System Size (kW).";
}
if (isNaN(annualProductionFactor) || annualProductionFactor <= 0) {
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter a valid Estimated Annual Production Factor (kWh/kWp).";
}
if (isNaN(solarSystemCost) || solarSystemCost < 0) { // Cost can be 0 theoretically, but typically positive
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter a valid Total Solar System Cost ($).";
}
if (address.trim() === "") {
inputsValid = false;
resultDetailsElement.innerHTML += "Please enter your address for context.";
}
if (!inputsValid) {
return; // Stop calculation if any input is invalid
}
// Calculations
var currentAnnualCost = annualKwh * currentRatePerKwh;
var annualSolarProduction = solarSystemSizeKw * annualProductionFactor;
var valueOfSolarEnergy = annualSolarProduction * currentRatePerKwh;
var estimatedAnnualSavings = currentAnnualCost – valueOfSolarEnergy;
// Ensure savings are not negative (e.g., if solar production exceeds consumption)
if (estimatedAnnualSavings 0) {
simplePaybackPeriod = solarSystemCost / estimatedAnnualSavings;
}
// Display Results
resultValueElement.innerHTML = "$" + estimatedAnnualSavings.toFixed(2);
resultDetailsElement.innerHTML =
"Estimated Annual Cost Without Solar: $" + currentAnnualCost.toFixed(2) + "" +
"Estimated Annual Solar Energy Produced: " + annualSolarProduction.toFixed(0) + " kWh" +
"Estimated Value of Solar Energy Produced: $" + valueOfSolarEnergy.toFixed(2) + "" +
(simplePaybackPeriod > 0 ? "Estimated Simple Payback Period: " + simplePaybackPeriod.toFixed(1) + " years" : "Estimated Simple Payback Period: N/A (Savings too low or zero)") +
"Based on estimated production for address: " + address + "";
}