Location & solar PV system
⚙ Advanced settings
🔄 Existing solar system
Household consumption
Your current electricity costs
Enter your current bill to anchor the ROI baseline. The model compares what you pay now versus what you'd pay after solar — the difference is your annual saving.
Solar generation preview
EV configuration
⚙ Advanced settings
EV demand summary
Monthly energy flows (daily average kWh)
Self-sufficiency & battery utilisation by month (%)
Seasonal performance summary
Custom battery size
Battery size comparison — monthly self-sufficiency
Battery utilisation — monthly average state of charge
7-day battery charge profile
See how each battery charges and discharges across a typical week for the selected month. Set the starting charge level to explore how quickly each battery settles into its natural daily cycle.
Each day shows 4 phases: pre-dawn (after overnight EV) → solar peak → evening (post-VPP dispatch) → midnight (after household draw). Y-axis is % of usable capacity.
Virtual Power Plant (VPP) modelling
A VPP programme lets your retailer dispatch your battery to the grid during peak demand events (typically 4–8 pm). You earn a peak export rate for the energy dispatched. Model how VPP participation affects your battery charge cycle and what size battery you need to participate reliably.
ROI components
Select which savings to include in the payback, NPV, and IRR calculations.
How the ROI is calculated
➕ Add installer proposal
⚙ Installer claims & validation fields
Questions to ask your installer
These questions are tailored to your current system configuration and update automatically as you change settings.
Visible sections
Electricity tariffs & financial assumptions
▶ Advanced settings Battery · Load profile · Free power · Inverter & EV · Validation tolerances
Battery assumptions
Load profile
EV assumptions
Free power window
Inverter & EV charging
Installer validation tolerances
Installed app — keeping it up to date
If you have added this app to your home screen (iOS, Android, or desktop), updates are delivered automatically via the service worker. Here is how it works and what to do if you want to force an update.
Ctrl+Shift+R (Windows/Linux) or Cmd+Shift+R (Mac) to bypass the cache and reload from the server.
Hot water system
Air conditioning
Cooking appliances
Pool, spa & outdoor
Other large appliances
Always-on baseline
Battery charging & free power window
When the battery charges during the free power window (11 am–2 pm), the inverter must simultaneously handle: solar DC conversion, battery charging current, household loads, and — if applicable — EV charging. The hybrid inverter's battery charger rating is the key constraint on how fast the battery can charge.
⚙️ Simulation settings
🏠 When do you run these appliances?
Set the typical time window for each appliance. Only appliances configured on the Inverter page appear here. The advisor compares your schedule against the solar curve and flags the best shifts.
📅 24-hour energy profile
💡 Optimisation recommendations
📈 Estimated annual savings from optimisation
Transfer settings
Export all your current settings to a file and load them into another device or browser — or share a configuration with someone else. The export includes all inputs, assumptions, installer proposals, and your current electricity bill.
Downloads a .solarsettings file containing your complete configuration.
Load a previously exported .solarsettings file to restore all settings.
About this brief
This document summarises your current situation, energy needs, and system requirements. Share it with installers so they can provide accurate quotes tailored to your setup.
It covers what you need, not projected savings — those remain on the Installer Check page.
Additional notes for installer
Anything else the installer should know — roof material, shading, switchboard location, brand preferences, etc.
How to use this guide
You've modelled your System — now it's time to get quotes. Use this guide to evaluate installers fairly, ask the right questions, and spot the red flags before signing anything.
Generate an Installer Brief from your inputs and share it with every installer you contact — it saves time and ensures you're comparing like-for-like quotes.
CEC accreditation — why it matters
Only Clean Energy Council (CEC) accredited installers are authorised to install grid-connected solar and battery systems in Australia. Accreditation is required to access STC rebates (Small-scale Technology Certificates) — your statutory right as a consumer. An unaccredited installer means you forfeit your rebate and may face council compliance issues.
What to look for in a solar installer
- CEC accreditation — verified, not just claimed
- CEC-approved products — panels and inverters must be on the CEC approved product lists to qualify for STCs
- Local presence — a local installer is easier to reach for warranty claims and after-sales service
- Workmanship warranty ≥ 10 years — separate from the product warranty; covers installation faults
- At least 3 years in business — the AU solar industry has had many fly-by-night operators; longevity matters
- Detailed written quote — brand names, model numbers, panel count, inverter size, estimated generation output, total cost including GST
- References and recent reviews — ask for 2–3 local customer references; check Google, ProductReview.com.au
- Electrical contractor licence — your state's electrical licensing body (e.g. NSW Fair Trading, Energy Safe Victoria)
Questions to ask your installer
- What is your CEC accreditation number? Can I verify it?
- Are all products on the CEC approved product lists?
- What is the estimated annual generation (kWh/year) for my roof and location?
- What workmanship warranty do you provide, and who backs it if your company closes?
- How long has your business been operating in this state?
- Who will actually perform the installation — employees or subcontractors?
- Will the system be monitored, and how will I know if it stops working?
- Does the quote include grid connection fees, metering changes, and any switchboard upgrades?
- What battery management system (BMS) is included, and does it support VPP enrolment?
- How do you size the battery — what inputs are you using for my household's usage profile?
Red flags to watch out for
- Pressure to sign immediately — "this price is only valid today" is a high-pressure tactic, not a genuine constraint
- No written quote with model numbers — verbal quotes or quotes without specific product details are meaningless
- Savings claims that exceed your current bill — mathematically impossible; likely inflated to close the sale
- Door-to-door sales — the ACCC has repeatedly flagged predatory solar door-knocking; always get competing quotes
- "Tier 1" panels without brand names — "Tier 1" is a Bloomberg financial rating, not a quality certification; demand brand and model
- No mention of STCs or rebates in the quote — you are entitled to your STC discount; it should be reflected in the price
- Unusually low price — below-market quotes often indicate cheap, unlisted components or subcontracted labour with poor accountability
- Unable to provide references — any reputable installer operating for 2+ years should have satisfied local customers
Get up to 3 free quotes from CEC-accredited installers
Solar Quotes connects you with up to 3 vetted, CEC-accredited local installers. They screen all installers, publish customer reviews, and have helped over 700,000 Australians get solar quotes since 2009.
Get free quotes via Solar Quotes →We may receive a referral fee if you proceed with an installer through Solar Quotes. This does not affect the independence of this tool's calculations or the quotes you receive.