PV Solar Panel Performance & Savings Calculator
Enter the total rated wattage of your solar panel system (e.g., 6000 for a 6 kW system).
The average number of hours per day your panels receive direct sunlight equivalent to 1000 W/m² (peak sun). This varies by location and season.
Accounts for real-world losses due to temperature, wiring, dust, shading, and inverter efficiency. Typically ranges from 0.7 to 0.85.
Your average cost per kilowatt-hour for electricity from your utility company.
Understanding Your Solar Panel Performance and Savings
A PV (Photovoltaic) Solar Panel Calculator helps you estimate the energy production and potential electricity bill savings from a solar panel system. This tool is crucial for homeowners and businesses considering solar energy, providing a clear picture of the system's financial and environmental benefits.
How Solar Panels Generate Electricity
Solar panels convert sunlight into direct current (DC) electricity. An inverter then converts this DC electricity into alternating current (AC) electricity, which is what your home appliances use. The amount of electricity generated depends on several factors, including the size and efficiency of your panels, the amount of sunlight they receive, and various system losses.
Key Factors in Solar Performance Calculation:
- Total System Wattage (Watts): This is the combined rated power output of all your solar panels under standard test conditions. For example, a 6 kW system has a total wattage of 6000 Watts. Higher wattage generally means more potential energy production.
- Average Daily Peak Sun Hours: This is a critical metric that represents the intensity and duration of sunlight your panels receive. It's not simply the number of hours the sun is up, but rather the equivalent hours of full sun (1000 W/m²). This value varies significantly by geographic location, season, and local weather patterns. Online resources and solar installers can provide accurate peak sun hour data for your specific area.
- System Derating Factor: In the real world, solar panels rarely perform at their absolute maximum rated capacity. The derating factor accounts for various losses, including:
- Temperature: Panels become less efficient as their temperature rises.
- Wiring Losses: Some energy is lost as electricity travels through wires.
- Inverter Efficiency: Inverters are not 100% efficient in converting DC to AC.
- Dust and Soiling: Accumulation of dust, dirt, or snow on panels reduces light absorption.
- Shading: Even partial shading can significantly impact overall system output.
- Panel Degradation: Panels slowly lose efficiency over their lifespan.
- Average Electricity Cost ($/kWh): This is the price you pay your utility company for each kilowatt-hour of electricity consumed. Knowing this allows you to translate your solar energy production into tangible financial savings.
Calculating Your Solar Energy Output and Savings
The calculator uses these inputs to estimate:
- Daily Energy Production (kWh): The total amount of electricity your system is expected to generate each day.
- Annual Energy Production (kWh): The estimated total electricity generated over a year.
- Annual Electricity Savings ($): How much money you could save on your electricity bills annually by generating your own power.
Example Calculation:
Let's say you have a 6000 Watt (6 kW) solar system in an area with 4.5 average daily peak sun hours. You estimate a system derating factor of 0.8, and your electricity costs $0.18 per kWh.
- Daily Energy (Wh) = 6000 W * 4.5 hours * 0.8 = 21,600 Wh
- Daily Energy (kWh) = 21,600 Wh / 1000 = 21.6 kWh
- Annual Energy (kWh) = 21.6 kWh/day * 365 days/year = 7,884 kWh
- Annual Savings = 7,884 kWh * $0.18/kWh = $1,419.12
This example shows that a 6 kW system under these conditions could produce approximately 7,884 kWh annually, leading to over $1,400 in electricity bill savings each year.
Important Considerations:
This calculator provides an estimate. Actual performance can vary due to real-time weather conditions, maintenance, and changes in electricity rates. For a precise assessment, it's always recommended to consult with a professional solar installer who can conduct a detailed site analysis.