Australian Design Solar
20kW solar systems for businesses and larger homes
Explore a larger rooftop solar system designed around your electricity demand, roof and future energy needs.
Australian Design Solar helps you assess whether a 20kW solar installation suits your property. We consider your consumption, available roof area and electrical setup before discussing equipment and installation options.
Compare solar-only and solar-with-battery options through a written quote for your site.
Understand your system
What is a 20kW solar system?
A 20kW solar array has approximately 20 kilowatts of combined panel capacity under rated test conditions. It generates electricity during daylight hours, with an inverter converting panel output for use at your property.
The panel capacity and inverter capacity are separate specifications. Your quotation should identify both, together with the panel count and individual panel wattage.
If a package uses a 20kW inverter with a larger panel array, ask for the actual array capacity to be clearly stated.
Start with electricity use
Who should consider a 20kW solar installation?
A larger system deserves a clear reason for its size. Share your bills and operating patterns so our team can assess how the proposed generation would be used.
Businesses with daytime demand
Offices, workshops, retail premises and other businesses can discuss whether their daytime consumption supports a system of this size.
Explore commercial solarLarger homes with substantial usage
High electricity demand, suitable roof space and future appliance plans may make a larger system worth assessing. Household size alone is not enough to choose capacity.
Explore residential solarProperties planning solar and storage
If battery storage is part of your project, discuss it early so generation, storage and inverter compatibility can be considered together.
Explore solar with batteriesPanel count and roof layout
How many panels make a 20kW solar system?
Panel count depends on the selected wattage. The examples below show the arithmetic for arrays at or close to 20kW; they are not advertised package inclusions.
| Panel wattage | Panel count | Total array capacity |
|---|---|---|
| 440W | 45 panels | 19.80kW |
| 450W | 44 panels | 19.80kW |
| 500W | 40 panels | 20.00kW |
For example, 50 × 440W panels equal 22,000W, or 22kW. A package with that array should identify it as 22kW of panels, even if it uses a 20kW inverter.
How much roof space is required?
Ask for a layout using the dimensions of the actual panels. As an illustration, 40 panels measuring 2.2m² each occupy 88m² of panel surface alone. That is not the total roof-space requirement: gaps, access, roof edges, obstacles and the arrangement of roof sections also need consideration.
Provide any roof plans or known roof issues when you enquire. Ask what roof-condition or structural assessment is required before installation.
Generation and performance
How much electricity will a 20kW system produce?
There is no single daily output that applies to every Australian property. Location, season, weather, shading, orientation and system losses affect generation.
Request an annual generation estimate with monthly figures for your proposed layout. A daily average does not describe every day’s performance or the amount your property will use directly.
For business premises, share interval consumption data where available so generation can be compared with working hours and weekend demand.
Illustrative output calculation
If a site assessment estimated a net daily yield of 4kWh per installed kW:
20kW × 4kWh/kW = 80kWh per day.
This is an arithmetic example using an assumed yield, not a forecast or guaranteed output for your property. Your quote should use site-specific assumptions.
Installed pricing
20kW solar system price in Australia
Australian Design Solar provides tailored quotations for 20kW solar installations. The price depends on the selected panels and inverter, installation conditions and any additional electrical work.
A useful comparison starts with the complete scope. Ask for exact models, total payable cost and clearly identified inclusions before choosing a package.
Equipment selection
Compare panel models, array capacity, inverter rating, monitoring features and the applicable warranty documents.
Installation requirements
Roof access, mounting, cable routes, switchboard work and any required assessments can affect the project scope.
Optional battery storage
Battery capacity, compatible inverter equipment and any requested backup configuration should be identified separately in the proposal.
Ask the quote to state its GST treatment, any incentive assumptions, payment terms and exclusions. Confirm whether connection or metering work is included.
Electrical and connection planning
Check your supply and export conditions early
Local network requirements can limit inverter capacity and electricity exports. The available options also depend on your property’s supply configuration.
Does the site need three-phase power?
Do not assume a 20kW inverter can be connected to your existing supply. Ask for the phase arrangement, inverter specification and network requirements to be checked before equipment is selected.
Can all surplus generation be exported?
Connection approval and export permission are different. Ask what export limit applies and whether export-control equipment or settings are included in the installation.
20kW solar with battery storage
Choose storage around your energy needs
A 20kW solar system does not automatically require a 20kWh battery. Solar capacity in kW and battery storage in kWh describe different things.
Tell us about electricity use outside solar hours, available surplus generation and your storage goals. We can discuss which battery configurations merit assessment alongside the solar system.
If backup matters, ask for supported circuits, output limits and outage operation to be specified. Backup should not be assumed to be included.
Explore complete solar and battery systemsDiscuss these details with our team
- Usable battery capacity and output power.
- Compatibility with the selected inverter.
- Battery location and installation requirements.
- Backup equipment and supported circuits.
- Expansion options and model-specific conditions.
- Product warranty and support arrangements.
From enquiry to installation
Your 20kW solar project, step by step
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Share your requirements
Send your location, electricity usage and property details. Mention existing solar and future energy plans.
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Assess the proposal
Discuss roof layout, equipment, site checks and connection requirements for the proposed system.
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Review your quote
Check the complete scope, total cost, approvals, warranty terms and installation arrangements.
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Install and hand over
Confirm access and any shutdown planning. Keep your system documents and monitoring information afterwards.
Australian Design Solar
A clear proposal for a substantial solar project
We help you compare your options with attention to the property, equipment and installation scope. Ask our team to explain how the proposed configuration relates to your requirements.
Learn more about Australian Design Solar and our approach to solar installation .
Understand your warranty cover
Panel performance warranties, product warranties and installation warranties cover different things. Review the documents for your selected equipment.
Read our Warranty Policy and ask about support arrangements before accepting your proposal.
Installation enquiries
20kW solar across our Australian service areas
Discuss your project in Sydney, Melbourne, Brisbane, Adelaide or Canberra. Provide your postcode so we can confirm availability and the assessment requirements.
Sydney enquiries include Norwest, Bella Vista, Castle Hill, Baulkham Hills, Blacktown, Seven Hills, Parramatta, Rouse Hill and surrounding areas.
For Melbourne and other locations, share your property details and whether the project is residential or commercial.
Your questions answered
20kW solar system FAQs
How much does a 20kW solar system cost?
We provide a tailored price based on equipment, roof access, electrical work and connection requirements. Battery storage and backup should be specifically identified if included.
How many panels are needed?
It depends on panel wattage. For example, 40 × 500W panels total 20kW, while 45 × 440W panels total 19.8kW. Check the exact count and array capacity in your quotation.
How much electricity will it generate?
Output depends on your site and system design. Ask for an annual estimate with monthly figures and clearly stated assumptions rather than a fixed daily promise.
Is 20kW suitable for a home?
It can be considered for a home with substantial demand and suitable roof and electrical conditions. A usage assessment should establish whether this size is appropriate.
Do I need three-phase power?
Your supply and local network requirements need assessment. Do not assume a 20kW inverter is permitted on an existing single-phase connection.
Can I add battery storage?
Battery options can be assessed with a new installation or as a later upgrade. Confirm inverter compatibility, electrical requirements and any future expansion conditions.
Will solar operate during a blackout?
Standard grid-connected solar normally shuts down during an outage. Backup requires suitable equipment and a specifically designed configuration.
How do I request a quote?
Complete the form near the top of this page or call 1300 85 1919. Share your postcode, electricity bill and project goals.
Plan your next step
Find out whether 20kW solar fits your property
Talk to Australian Design Solar about your electricity demand, roof and battery plans. Request a tailored quote with the details you need to compare your options.