How large a 100kW system is, how many panels and what financial incentives are available to your business. Learn more.
Note: We have updated this post as of 2026 to include the most up-to-date information for solar customers. If you have questions related to large solar energy systems, please contact our team, who are knowledgeable, experienced, and happy to help.
If you’re a large business or run a small business with a large property, and you’re considering a large commercial solar energy system, you may have a lot of questions.
We’ve written this post to help answer some of those questions for you. After reading this, you should be a little bit closer to making a decision on whether a large-scale commercial solar energy system is right for your business.
So, let’s dive in with the big questions about large-scale commercial solar…
If you are wondering how many panels are needed for a 100 kW solar system, you can expect a solar energy system of that size to be around 200 panels. Panel sizes have typically increased, and for 100 KW systems, we’re installing 200 x 500W. Panels are 1.2m x 2.1m – around 500m².
This is where large, flat roofs can prove useful.
You can expect a 100 kW system to produce roughly 350 to 450 kWh per day. If you’re a large business with significant electricity consumption and an annual power bill of about $50k, this could potentially reduce your energy bills by approximately 30%.
Nevertheless, this estimation is contingent upon various factors such as local climate conditions, seasonal variations, the quality of your system, and any potential obstacles to sunlight.
Frankston Council selected Energy Makeovers as a partner to install a whopping 532kW solar energy system on the Peninsula Aquatic Recreation Centre. This installation included 1,047 Trina Solar panels and 4 x Sungrow 100kW inverters.
According to the Council:
“The money saved on electricity costs from both of these sites will be used to deliver other important community services and projects.”
It really varies, dependent on:
To give you some kind of an answer that you can work with – let’s say $1.50 – $2 per watt.
There are Federal Government incentives for systems over 100kW through the Renewable Energy Target (RET). The RET splits into two:
businesses can generate large-scale renewable energy certificates with solar energy installations over 100kW.
It’s a little complicated, as you are considered a ‘power station’ and you generate Large-scale generation certificates (LGCs) on an on-going basis. This means there isn’t an upfront rebate or subsidy available at purchase, but your system payback period is reduced over time.
Your rebate is based on how much energy your system generates – 1 MWh equals 1 x Large Generation Certificate. Certificates are typically surrendered annually and traded through a broker. Without getting into the nitty gritty, we’ll use a 200kW system as an example, using today’s market prices on certificates. This example business could expect to make the following:
If you require initial support on the up-front cost due to your cash flow and business needs, you may instead need to reduce your solar energy system size below 100kW to take advantage of small-scale certificates (STCs).
So, it’s complicated, but you can see from the example above that it can provide a significant rebate over time. If you need help understanding if your business could benefit from LGCs for a large-scale commercial solar energy system, our solar energy experts are happy to discuss your options.
Just get in touch – 1300 788 776. We have a commercial solar energy page with more information, too.
There are no State Government incentives in Victoria for solar energy systems over 100kW.
As above, if you opt for a solar energy system that is more than 100 kW, it moves you into the LRET bracket, and you become ineligible for STCs. STCs provide an upfront rebate through SRES.
Current STCs created per kW are (1 x 6 x 1.185 = 7.11 x $38.5 = $273)
Example: 99.9kW = 99.9 x 6 x 1.185 = 710 x $38.5 = $27,335
You can apply for multiple rebates per site, as long as it’s less than 100kW total. ie. install 50kW today, claim the rebate and install 40kW in the future and claim the rebate again. But, the combined figure is not 100kW.
So, you need to assess both options and decide which is right for your business.
Energy Makeovers are proud to be an Approved Seller through New Energy Tech. This means, as a customer, you can rest assured you’ve selected a solar energy supplier and installer with high standards and experience. It also means we are approved to pass eligible rebates on, as applicable.
We use SAA Accredited Installers. Solar Accreditation Australia (SAA) certification confirms that solar designers and installers have met recognised industry benchmarks and completed the appropriate training. Holding this accreditation is essential for accessing Small-scale Technology Certificates (STCs) and is frequently required to qualify for government incentives and rebates within the solar sector.
This was previously referred to as the Clean Energy Council Approved Solar Retailer.
We remain existing members of the Clean Energy Council. Being part of the CEC means we are at the forefront of Australia’s energy transformation—collaborating with key players across government and industry to push for a cleaner, smarter, and more competitive energy market.
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