Estimate your solar panel system's daily electricity generation.
(Hours of direct sunlight equivalent to 1000 W/m²)
85%
Estimated Daily Production:
— kWh
Understanding Your Solar Panel's Daily kWh Production
This calculator helps you estimate the amount of electricity (measured in kilowatt-hours or kWh) your solar panel system is likely to produce on an average day. This is a crucial metric for understanding the potential savings and the environmental impact of your solar installation.
How the Calculation Works
The core of the calculation involves a few key factors:
Solar Panel Wattage (W): This is the rated power output of a single solar panel under standard test conditions (STC). Higher wattage panels produce more power individually.
Number of Panels: The total number of solar panels installed in your system.
Peak Sun Hours: This represents the average daily hours of sunlight that are equivalent to 1000 Watts per square meter (W/m²). It's not the same as total daylight hours; it accounts for the intensity and angle of the sun. Locations closer to the equator and with clearer skies generally have higher peak sun hours.
System Performance Ratio (%): Solar systems aren't 100% efficient. This ratio accounts for energy losses due to factors like temperature, shading, dirt on panels, inverter efficiency, and wiring resistance. A common range is 75% to 90%.
The formula used by this calculator is:
Total System Wattage (W) = Panel Wattage (W) * Number of Panels
Daily Energy Production (Wh) = Total System Wattage (W) * Peak Sun Hours (h) * (Performance Ratio / 100)
Daily Energy Production (kWh) = Daily Energy Production (Wh) / 1000
Example Calculation:
Let's consider a system with:
Panel Wattage: 350 W
Number of Panels: 12
Average Peak Sun Hours: 5.0 hours
System Performance Ratio: 80%
1. Total System Wattage: 350 W/panel * 12 panels = 4200 W
2. Daily Energy Production (Wh): 4200 W * 5.0 hours * (80 / 100) = 16,800 Wh
3. Daily Energy Production (kWh): 16,800 Wh / 1000 = 16.8 kWh
So, this system would be estimated to produce approximately 16.8 kWh per day.
Why is this Important?
Estimating your daily kWh production helps you:
Assess Financial Savings: Compare the generated kWh to your household's energy consumption to estimate potential reductions in your electricity bills.
Understand System Sizing: Determine if your current system is appropriately sized for your energy needs or if adjustments are needed.
Monitor Performance: Use the estimated value as a benchmark to compare against actual system output, helping to identify potential issues or degradation over time.
Environmental Impact: Quantify the amount of clean energy your system is contributing, often expressed in terms of carbon emissions offset.
Remember, this is an estimate. Actual production can vary based on weather patterns, seasonal changes, panel orientation and tilt, and specific site conditions.
var performanceRatioSlider = document.getElementById("performanceRatio");
var performanceRatioOutput = document.getElementById("performanceRatioValue");
performanceRatioSlider.oninput = function() {
performanceRatioOutput.innerHTML = this.value + "%";
}
function calculateKwh() {
var panelWattage = parseFloat(document.getElementById("panelWattage").value);
var numberOfPanels = parseFloat(document.getElementById("numberOfPanels").value);
var peakSunHours = parseFloat(document.getElementById("peakSunHours").value);
var performanceRatio = parseFloat(document.getElementById("performanceRatio").value);
var resultElement = document.getElementById("result-value");
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return;
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if (isNaN(numberOfPanels) || numberOfPanels <= 0) {
resultElement.innerHTML = "Invalid Input";
resultElement.style.color = "#dc3545";
return;
}
if (isNaN(peakSunHours) || peakSunHours < 0) {
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}
if (isNaN(performanceRatio) || performanceRatio 100) {
resultElement.innerHTML = "Invalid Input";
resultElement.style.color = "#dc3545″;
return;
}
var totalSystemWattage = panelWattage * numberOfPanels;
var dailyProductionWh = totalSystemWattage * peakSunHours * (performanceRatio / 100);
var dailyProductionKwh = dailyProductionWh / 1000;
resultElement.innerHTML = dailyProductionKwh.toFixed(2) + " kWh";
resultElement.style.color = "#28a745"; // Success green
}