Which Solar Battery Is Right for Your Home?

If you have solar panels or are thinking about getting them, you may have heard about solar batteries. And for good reason. Adding a battery lets you store solar power made during the day. You can use it later when the sun isn’t shining. But with so many battery options out there, how do you choose the right one?

At Shoalhaven Solar, we have assisted many local homeowners. We have also helped businesses in the South Coast and Southern Highlands. This guide will walk you through the key things to consider, with practical examples and product comparisons based on what we see every day.

Why Choose a Solar Battery in the First Place?

Before we dive into the options, let’s look at why adding a battery makes sense:

• Reduce reliance on the grid – especially during peak evening hours.

• Save more on your electricity bill – by using your stored solar rather than buying power at night.

• Keep the lights on during blackouts – some systems offer full backup for your home.

• Prepare for the future – with growing demand from EVs and all-electric homes, batteries give you flexibility.

Key Factors When Choosing a Solar Battery

Every household is different, and the "best" battery really depends on your setup, power usage, and budget. Here are the top factors to consider:

1. Do You Have Single-phase or Three-phase Power?

In the Shoalhaven region, most homes in town are single-phase. But rural properties and newer housing estates are increasingly wired for three-phase.

• Single-phase systems are simpler and more common, and most battery systems are designed to suit them.

• Three-phase systems can manage larger power loads, like fast EV chargers and ducted air conditioning. However, not all batteries support three-phase backup, which is an important point to note.

For example: Tesla Powerwall supports three-phase homes, but only backs up one phase in a blackout. Sigenergy SigenStor provides complete three-phase backup. This means your entire house can stay powered during an outage.

2. Do You Want Blackout Protection?

Some batteries work during blackouts. Some don’t. Others only back up limited circuits, like your fridge and a couple of lights.

• Full backup systems, like Sigenergy or Tesla with add-ons, are great if you live in an area with blackouts. This is common around Berry Mountain, Kangaroo Valley, or other remote properties.

• Partial or no backup systems, like AlphaESS, can help you store and use solar energy. However, they won't keep all the lights and power on if the grid goes down.

3. How Much Space Do You Have for the Battery?

Batteries are typically wall-mounted, often in a garage or side passage. But space matters:

• Do you need to park a car nearby?
  Is there enough clearance to meet safety regulations?

• Does the battery’s size or shape suit your space?

A customer recently chose the Anker battery. Its slim design saved 80mm. This was enough to fit their vehicle comfortably in the garage.

4. Is It Compatible With Your Existing Solar System?

Not all batteries work with all systems. Some are “AC-coupled” and can be added to almost any setup. Others are more particular and need a matching inverter brand.

• Retrofit-friendly options: Tesla Powerwall, AlphaESS, Sigenergy — easy to add to older systems.

• Brand-specific batteries: May require inverter upgrades, which adds cost.

If you plan to add solar in the future, choose a battery that works well with different systems. This way, you won’t be locked in.

5. Can You Expand the Battery Later?

Household energy needs grow, especially with EVs on the rise. Some battery systems are modular, meaning you can add more capacity over time.

• Modular systems like Sigenergy let you expand in 5kWh or 8kWh blocks.

• Non-modular systems, like the Tesla Powerwall or AlphaESS, need you to buy a whole second battery. This option is more costly and less flexible.

6. What’s Your Budget?

Solar batteries range in price:

• Entry-level (AlphaESS): from $7,000

• Mid-range (Anker): around $9,000–$10,000

• Premium (Tesla Powerwall or Sigenergy): $11,000–$13,000+

We always help customers weigh up the cost against what they’ll get out of the system. If you just want to reduce bills and store excess solar, a budget option may suit. But if blackout protection, EV integration or future expansion is important, investing more upfront can pay off long term.

Compare Popular Batteries at a Glance

Visit Our Showroom or Speak With an Expert

At Shoalhaven Solar, we believe in offering choice. That’s why we stock and display over 9 batteries in our Highlands showroom — not just 1 or 2 like many solar retailers.

Come and see the differences for yourself. We’ll take you through the pros and cons of each, based on:

• Your current solar setup

• Your home’s power configuration

• Whether you want blackout protection

• Your EV and future plans

• And, of course, your budget

We’re locals — and we know how to design battery systems that suit Shoalhaven and Southern Highlands homes.

Still Unsure? Let Us Help You Decide

We are working on an online “Help Me Choose” tool. This tool lets you filter batteries based on what matters to you, like backup power, budget, space, and more. In the meantime, we’re just a phone call away.

Call Shoalhaven Solar today on (02) 4464 1597 or request a quote to find the right battery solution for your home.