Battery Backup & Solar Storage

HOME BATTERY BACKUP & SOLAR ENERGY STORAGE

Reliable Power

When the Grid Goes Down

A home battery backup system can keep essential equipment running during a power outage, from refrigerators and lights to internet equipment, well pumps, and heating systems. When paired with solar, battery storage can also recharge from the sun and give you greater control over how your energy is used.

South Sound Solar designs battery backup systems for homes and businesses throughout Olympia and Western Washington. The right system depends on the battery capacity, the equipment you want to power, and how much stored energy you reserve for an outage.

Franklin Battery Backup System from United Churches Project

Battery Backup Planning Tool

What could your battery keep running?

Choose a battery, the season, and the items you would want during an outage. We will estimate how long your stored energy could last.

1

Choose your battery system

Already have a battery? Select it below. Still planning? Compare different sizes and quantities.

Learn more about Tesla Powerwall ↗
2

Plan for the season

Winter outages usually mean less solar recharge and more heating demand. Summer often brings more solar, but cooling can add load.

Winter view: treat this as a conservative stored-energy estimate. Several cloudy days may limit how much solar can refill the battery.
3

Choose what you want to keep running

Basic essentials are included automatically because nearly every home needs them. Add anything else you would want during an outage.

Fine-tune your outage starting point

These controls let you test a more specific “what if?” situation.

Use the wattage label on the device when available.

100%

How full is the battery when the outage begins?

10% nearly empty50% half full100% full

Drag the slider left to test an outage that starts after some stored energy has already been used.

Loading live calculator…

Your estimated backup time

hours

Choose at least one item above to see an estimate.

Battery system1 Tesla Powerwall
Stored energy13.5 kWh
Estimated demand0 W

Selected items: None yet

What this means

Choose the items you would want during an outage. The calculator will show how your choices affect the estimated backup time.

Winter reminder: This shows how long the energy already stored may last. Actual solar recharge can be limited during dark or stormy weather.

Every home is different. South Sound Solar can review your actual equipment, priorities and outage goals.

Talk with our local team

Estimates use average continuous loads and the selected battery model's stated conversion efficiency. Appliances and motors cycle and may briefly draw much more power. Results are educational estimates, not a guarantee of system performance or compatibility.

South Sound Solar Battery Backup Calculator · Version 1 · August 7, 2026

Custom Proposals

Our solar sales specialists create a custom proposal based on your unique needs. We use professional shade analysis tools to find the ideal location for the array and if shading is an issue, we will discuss a ground mounted solar array. We will go over your budget, energy usage, and possible financing options. No 2 customers or solar arrays are the same and we want to make sure yours is right for you!

Aerial view of a house with multiple solar panels installed on the roof, surrounded by trees and a backyard.
Interested In Solar Electricity?

We Offer Free Site Surveys!