Solar System Size Calculator

What Size Solar Power System Do I Need?

Use this guide to accurately determine the size of the solar power system you need to power your home or specific appliances. Properly sizing your solar system ensures that you can reliably meet your energy needs, optimize efficiency, and achieve cost savings.

---

Understanding Key Components

• Wattage (W): This measures the instantaneous power an appliance uses. Think of it as how "thirsty" for electricity an appliance is at any given moment.
  
  Example: A typical 20 cubic feet refrigerator (standard size for most households) might use about 150W when running.
• Watt-Hours (Wh): This measures energy use over time. It's calculated by multiplying wattage by the number of hours used.
  
  Example: If that 150W refrigerator runs for 8 hours, it uses 1,200 Wh (150W * 8 hours).
• Kilowatts (kW) and Kilowatt-Hours (kWh): These are just bigger versions of watts and watt-hours, used for larger measurements.
  1 kilowatt (kW) = 1000 watts (W)
  1 kilowatt-hour (kWh) = 1000 watt-hours (Wh)
  
  Example: Our 150W refrigerator running for 8 hours uses 1.2 kWh.

Solar System Components

• Solar Panel Array: This is all your solar panels combined. Its size is measured in watts (W) or kilowatts (kW) and determines how much energy you can generate under peak sunlight.
• Battery: This stores the energy your panels generate for use when the sun isn't shining. Battery size is measured in watt-hours (Wh) or kilowatt-hours (kWh).
• Inverter: This converts the DC power from your panels and batteries into AC power that your appliances can use. Its size, in watts or kilowatts, determines how many appliances you can run at once.

Factors Affecting Solar System Size

• Daily Energy Consumption: The total energy all your appliances use in a day.
• Sunlight Hours: How much sunlight your location gets. More sun means more energy production!
• Days of Autonomy: How many days you want your system to run without sunlight (using just stored battery power).
• System Efficiency: Various factors can reduce your system's output. We usually account for 20-25% energy loss to be safe.

Using the Solar Calculator

Step 1: Input Your Appliances

• Click the Add Appliance button to start a new entry.
• Choose an appliance from the dropdown list, or select "Custom" for unlisted items.
• For preset appliances, the wattage is filled in for you. Just adjust the number of items and hours used.
• For custom appliances, enter the wattage yourself, then set the number of items and hours of use.
• The calculator will automatically figure out the Total Watts and Watt-hours.
• To remove an appliance, click the "x" button at the end of its row.
• Check the total watt-hours at the bottom of the list or in the breakdown section.

Step 2: Understand the Results

• Daily Energy Consumption: How much energy all your appliances use in a day.
• Solar Panel Array Size: How big your solar panel setup should be.
• Battery Size: How much battery storage you need.
• Inverter Size: How powerful your inverter should be.
• You can adjust the Days of Autonomy to see how it affects your battery size. This is how long your system can run without sunlight.
  
  Example: If you use 5,000 Wh daily and want 2 days of autonomy, you might need a 10,000 Wh battery.

Building Your System

Solar Panel Array

• Combining Panels: You can mix and match panels to reach your target size.
  
  Example: For a 1200W array, you could use:

  • Six 200W panels, or
  • Three 400W panels
• Choose based on what's available, your space, and your budget.

Battery Storage

• Combining Batteries: Combine batteries to meet your storage needs.
  
  Example: For 26,000 Wh (26 kWh) storage, you could use:

  • Two 13 kWh batteries, or
  • Four 6.5 kWh batteries

Inverter Capacity

• Choosing an Inverter: Choose an inverter that can handle your maximum load.
  
  Example: If you need a 3 kW inverter, choose one that's at least that size.

Pro Tip: Some appliances like air conditioners need extra power to start up. Make sure your inverter can handle these brief power surges!

• When selecting your inverter size, consider your future needs too. Think about appliances you might add in the next 5-10 years, like a larger refrigerator, a home office setup, or a window air conditioning unit. It's often more cost-effective to install a slightly larger inverter now than to replace it later. For instance, if your current needs require a 4 kW inverter, but you're planning to add a window AC unit (which might need 1.5 kW) and a home office setup (around 0.5 kW), consider getting a 6 kW inverter instead. This gives you room to grow and can be more efficient in the long run.

Quick Compatibility Tip: When selecting your components, make sure they're all compatible with each other, especially in terms of voltage. Solar systems typically operate at 12V, 24V, or 48V. Ensure your panels, batteries, and inverter all work together at the same voltage. When in doubt about compatibility, don't hesitate to call us! We're here to help you build a system that works seamlessly.

Optimize Your System

• Try different combinations of appliances in the calculator.
• Adjust usage hours to match your real-life patterns.
• Remember, the calculator already accounts for some efficiency loss and battery usage.
• Make sure your inverter can handle all your appliances running at once.

Review and Seek Advice

If you're unsure about anything or want a professional opinion:

• Speak with a Solar Pro!
• Call us at +1 (877)-556-3347

We're here to help you design the perfect system for your needs!

Important Notes

• Our calculator makes some assumptions about sunlight and efficiency. Your actual needs might vary based on your specific location and conditions.
• This tool provides estimates. Your final system might need some adjustments.
• For complex setups or if you're unsure, always consult with a professional!

Conclusion

Congratulations! You now have a good foundation for understanding and sizing your solar power system. Remember, proper sizing ensures you have reliable power while optimizing efficiency and costs. Use this guide as a starting point, and don't hesitate to reach out for expert advice as you plan your solar energy setup. Happy solar powering!