The Case for Battery Storage

What happens when the lights go out? A common misconception about solar PV is that it will automatically keep your power on during an outage. Solar PV-only systems are required to shut down during grid outages, according to National Electrical Code (NEC) article 690.12. When electricity from a solar PV system sends energy out to the grid during an outage, the system is doing what is known as “Islanding.” Islanding can electrify power lines when they otherwise wouldn’t be, creating a dangerous situation for utility workers when the grid goes down and needs repairing.

Your Own Microgrid

When you add an energy storage system (ESS, also known as battery backup) to your PV system, homeowners can isolate themselves from the grid during an outage and keep their power on. Energy storage systems carry features to sense when the grid goes, providing a seamless transition to using your stored energy.

With battery and solar paired, you are creating a small microgrid for your home where you can significantly extend the amount of autonomy you have from the utility grid.

Finding your Battery Solution

Adding batteries to your system is more tricky than installing a typical PV system. Every site has a different electrical setup and goals for its backup and solar needs. NWES will help you find the best fit for your needs, whether PV only, battery backup only, or a PV and ESS pairing. We investigate how your home is electrically connected and will identify how much battery and solar you need depending on the loads you want to backup and for how long.

Considerations for Installing Batteries

Our primary battery offering is the Tesla Powerwall 2 AC. Each Powerwall will increase the size of loads you can back and the duration you can have backup power during a utility outage. When adding batteries to your home, we take into consideration the location of the following equipment:

Adding Equipment

Load centers are not needed with every install but can be used to isolate critical loads you want during an outage.

The Brains of the Battery

The Backup Gateway (BUG) this device manages the electricity flow that charges the battery and powers your home.

Fitting The Pieces Together

Conduit will connect between these components, terminating in either the meter or electrical panel, wherever the final point of interconnection is. Equipment can be inside your garage or on the exterior of your home, so penetration between the walls is typical.


The batteries, spec. sheet can be found in our Documents & Downloads page where you can find information on clearances (meant for ventilation) and dimensions.

The Clean Energy Combo

A solar PV system is not complete without considering battery storage. Batteries are the critical piece that gives you the flexibility to store and use your energy as you see fit. When a grid outage occurs, you can rest assured that your stored energy will kick into action within seconds. The future of modern home living is available to you today; make sure you control how you use, generate, and store energy!

user profile image for Manuel Larrain
Manuel Larrain
Manuel Larrain is a Chilean-born US citizen who studied business and sustainability at Western Washington University. Solar energy is his passion, as it is transforming how Washingtonians power their lifestyle. He believes we can address climate change, environmental justice, and steward a brighter future for all of us through renewable energy.