In today’s green energy landscape, solar power systems are more popular than ever. However, homeowners often stumble when it comes to sizing their solar systems effectively. This blog post aims to help you avoid one of the most common errors when sizing solar systems for homes. The post is based on a video I shared on my YouTube channel before, so if you prefer to watch the video, it’s right here:
I’m eager to share some essential solar power tips based on my own personal experience. When sizing a solar system for my home, if I simply took into account my energy consumption over the past year, I would have needed a 10 to 11-kilowatt system, which is approximately 33 panels on the south-facing side of my roof.
However, what’s often overlooked in sizing a solar system is planning for future energy needs. For instance, I’m planning to swap out my internal combustion cars for electric vehicles (EVs) within the next 18 to 24 months. With EVs, we need to account for charging demands and increased energy consumption.
My aim is to avoid situations where you install a system, and in a few short years, it’s well under what you need. The last thing I want is for you to end up with an electricity bill because you’re not meeting your demands. So how many solar panels do you need to charge a Tesla?
Sizing Solar Systems for EVs: A Detailed Example
Let’s delve into the specific example of my home solar system, sized to accommodate a cyber truck and a Tesla Model Y. This situation illustrates the surprising extent to which EVs can increase your need for a robust solar system.
So, how did I figure out my solar needs? I put together a spreadsheet that allows you to select your car and see how this affects your solar requirements. In this spreadsheet, I selected a Model Y and a Tesla Cyber Truck. However, you can select another car according to your needs.
This spreadsheet is designed to estimate the number of kilowatt-hours we’re going to consume for every mile driven, given different models of cars. With the Model Y and Cyber Truck, I estimated daily consumption of 11 kilowatt-hours and 26 kilowatt-hours, respectively.
After considering the energy consumption of the EVs, I calculated the number of solar panels I would need based on factors like system efficiency, peak sun hours, and the wattage of the panels. In the end, I found that I would need an additional 11 kilowatts – which means I need to double the size of my original system!
The Importance of Net Metering
Keep in mind that I live in Illinois, where we have net metering. This allows me to provide a surplus of power during the daytime and receive credits from my utility. At night, when my solar panels aren’t producing power, I can use those credits to charge my truck.
Remember, though, not all states or utilities offer net metering, and sometimes, they only provide a partial return on your energy input. In those cases, storing solar energy for future use with a battery makes more sense.
Here to Help
I hope this guide has been useful in helping you understand how to size your solar system correctly. If you have any questions, feel free to comment below.
If you need help designing your system to meet your needs, now and in the future, we at Everyday Solar are here to assist you. We can also connect you with a network of trusted nationwide installers. You’ll find the link to the spreadsheet right here, so you can adjust the numbers to fit your household.