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Three-Phase Solar Battery for a Three-Phase Home: Necessary or Overkill?

Single-phase power distribution is a typical setup for households with low energy demands. Some homes utilise three-phase power to accommodate their increasing energy needs. If you have a three-phase power and want to add a battery to your solar system, do you need a three-phase battery to match your house? Well, not necessarily and here's why:
Kathy Calilao
Updated at
Reading time
3 min

A Quick Refresher to Single-Phase vs. Three-Phase

The main difference between three-phase and single-phase power is how the electricity flows.

In single-phase power, there's one lane for the electricity to travel through. But in three-phase power, it's more like having three lanes, each with electricity flowing at different times.

As a result, the three-phase offers a more balanced current distribution, which makes it suitable for heavier loads like commercial buildings.

Single-phase power is straightforward and cheaper, which makes it suitable for homes and small businesses.

Single phase is more common in powering appliances like lights, TVs, and refrigerators. However, larger appliances with higher power demands, like air conditioners or workshops with heavy machinery, might require three-phase power.

Single-Phase Batteries: A Simpler, More Affordable Solution

Single-phase batteries like Enphase and Tesla Powerwall are the most common and generally more affordable options. They're a practical choice for backing up essential appliances in a three-phase home.

It is, as long as you're comfortable with losing power to your three-phase devices (like air conditioners or large machinery) during an outage. Here's why:

  • Power Surge Capability: Single-phase batteries focus all their power on one output, making them excellent for starting motors like refrigerators or pumps.

  • Easy to Install and Maintain: They're widely available and compatible with most solar inverters.

Enphase IQ Battery at the side of the house

Three-Phase Batteries: For Uninterrupted Power

While less common, three-phase batteries are the way to go if you need all your appliances running during a blackout. It includes those three-phase loads like air conditioners or workshop machinery. However, there are some trade-offs to consider:

  • More Expensive: They're more expensive to purchase and install than single-phase systems. The upfront investment can be significant.

  • Limited Surge Capacity: Their power is divided among the three phases, potentially limiting their ability to handle large surges from motors. It might not be an issue if your critical appliances have smaller startup loads.

Home Appliances

Understanding Your Needs and Priorities

Here are some guide questions and answers to narrow down your choices when it comes to picking the right battery system for your household:

  1. Can I prioritise essential loads in one phase? A single-phase battery is enough if you put all the crucial appliances into one phase. It can effectively back up these circuits during an outage. A qualified electrician can help you identify and prioritise these circuits.

  2. How critical are my three-phase appliances? If your air conditioner is vital during hot summers or you have a workshop at home, a three-phase battery might be worth the investment.

  3. What's my budget? Single-phase is generally more budget-friendly. If upfront cost is your first concern, a single-phase system can be the most practical solution.

Ultimately, the best choice depends on your priorities and budget. Learning these options can help you achieve the solutions well-suited to your needs.

Read up next our ultimate guide to solar batteries in 2024 to learn more about how battery storage can help expand your energy savings. Or you can directly ask our solar experts about the available energy and financing solutions for you.

Call us today at 1300 525 451 or fill in your details below to request for a solar or home battery storage quote today to see how much you can save!


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