What you need to know before adding storage to a new, existing, or a buildable net-metered system!
Adding storage to your grid-tie PV system allows you to power your home with or without the utility grid present. With storage as part of your home energy system you will continue to have power even when utility disruptions occur. Grid-Tie PV systems only produce power when the utility grid is detected. During a utility disruption, a grid-tie only system stops producing power until power is restored. If you want to be able to produce, consume and store your energy for when you need it most, it may be time to consider solar + storage.
Homeowners and businesses now have more *ESS options than ever before. This article will cover *Energy Storage System basics and will shed light on some of the considerations you need to consider before adding storage into your home.
What size system do you need and how do you figure that out?
There are a few main factors to consider:
- What is your total monthly kWh usage over an annual basis (average of the past 2 years is helpful if the data is available)?
PV Watts, a web site hosted by the National Renewable Energy Laboratory (NREL) is a great tool to estimate the size system you need by entering in your specific site data. You can also reach out to a solar company for assistance in sizing and selecting the best system for your application. Knowing the size PV system you need for 70, 80, 100% off-set will help guide your equipment selection and determine the best options for your application.
- What are the critical loads that you would need to back-up if the utility grid was not available? Reference our downloadable load calculation form here. Click here to download our EcoDirect off-grid load calculator.
Most batteries can’t power an entire home for very long. To extend the amount of time your battery lasts during an outage, you can choose to power only a few critical appliances in your home (such as the refrigerator and lights). The critical load subpanel allows you to choose those critical loads and it’s very important that solar installers set this up correctly for your battery’s capacity.
If you have an existing system, do you know the size of your current PV array, and the make, model, quantity, and inverter that is already connected to it? This information is integral for determining what storage options are available. The manufacturer could have a storage add-on or retrofit option, or you may want to consider AC coupling as that would save you time from rewiring the entire system. For either, you need to know what you already have installed to know what you can add-in.
Education is at the forefront of the solar industry, and it is our hope that you find many of the answers that you are looking for here. If there is a topic you would like to learn more about, please comment and share your questions below. We look forward to working with you.