When researching solar for your home, one system size keeps popping up: 6.6 kW. It’s by far the most common solar installation across Sydney — but why is it so popular? From affordability and government rebates to energy output and payback period, a 6.6 kW solar system offers the perfect balance for most households.

If you’re considering solar panels for your Sydney home, here’s why a 6.6 kW system might be the right choice for you.

A 6.6 kW solar system typically includes around 16–20 solar panels (depending on panel wattage, usually 330–415W each) paired with a 5 kW inverter.

Why the 5 kW inverter? Under Australian regulations, most residential properties on the grid are limited to a 5 kW inverter export capacity. Pairing it with 6.6 kW worth of panels slightly “oversizes” the system, which maximises energy production without breaching network rules.

For most Sydney households, a 6.6 kW system generates enough electricity to cover the majority of daytime energy needs, while remaining affordable compared to larger systems.

• Average daily output: 22–28 kWh (depending on roof orientation and shading).

• Annual savings: Up to $2,500–$2,700 per year on electricity bills.

• System cost (2025): After federal rebates, most 6.6 kW systems in Sydney cost between $5,000 and $8,000 depending on equipment quality.

This sweet spot between price and production makes it the most sought-after system size for families.

The Small-scale Technology Certificate (STC) rebate is one of the biggest reasons for the popularity of 6.6 kW systems. The larger the system, the more STCs you receive, which directly reduces your upfront cost.

For Sydney homeowners, a 6.6 kW system is large enough to maximise federal rebates but small enough to remain eligible for standard single-phase grid connections.

Most Sydney homes have roof space for around 16–20 panels, making a 6.6 kW system a practical option without requiring significant roof modifications. It’s also the right size for:

• Families of 3–5 people using power throughout the day.

• Households with work-from-home setups.

• Homes with air conditioning, pools, or high appliance usage.

For many families, it’s a “set and forget” system size that balances space, cost, and savings.

A well-designed 6.6 kW system in Sydney usually pays for itself in 4–5 years, depending on household usage and electricity prices. With solar panels lasting 20–25 years, that means two decades of low-cost or even free electricity once the system has paid itself off.

Add a solar battery, and your system can provide evening energy independence as well — reducing your reliance on the grid even further.

Because 6.6 kW systems are so widely installed, there’s an abundance of data showing their performance in Sydney’s climate. Installers like MPV Solar have decades of experience designing and installing this system size, ensuring it runs reliably and delivers strong returns year after year.

Not all solar installers are the same. At MPV Solar, we’ve been helping Sydney homeowners since 1992 with solar systems designed for long-term performance.

• Family-owned and operated

• No subcontractors — only our in-house, accredited electricians

• Tailored designs for your home and energy usage

• Honest advice on panels, inverters, and batteries

• Ongoing after-sales service and support

When you choose MPV Solar, you’re not just buying panels; you’re investing in a reliable, trusted partner for the life of your solar system.

A 6.6 kW solar system offers the perfect mix of affordability, efficiency, and long-term savings for Sydney homeowners. Whether you’re looking to cut your electricity bills, reduce your carbon footprint, or prepare for a battery or EV future, MPV Solar has the expertise to make it happen.

Contact MPV Solar today to book your free quote and consultation.