The main benefit of solar is in offsetting consumption rather than maximising exports of electricity to the grid in order to receive a feed-in tariff. This means that the ideal system size would be one that closely matches your electricity usage while not exporting excessive amounts of energy back into the grid.

For more information about installing solar read the Clean Energy Council's Guide to installing solar

With many different products and retailers on the market, making a decision can be difficult. Make sure you understand exactly what you are signing up to and carefully research the products and suppliers before signing a contract.

Potentially misleading statements

As a guide, a typical 1.5 kilowatt (kW) solar panel system installed in Victoria can produce up to around one third of an average household's daily energy consumption1. So, while you could potentially offset your entire electricity bill with solar power, it would take a larger than average (and generally more expensive) system to do so.

Questions to ask:

  • How much of my household's electricity consumption will I offset with this system?
  • What size system do I need to offset all of my electricity usage?
  • How much excess electricity might I be able to feed back into the grid?
  • What types of panels are available and how are they different?

Don't allow yourself to be pressured into an on-the-spot sale, and be sure to compare quotes and do your research. You may also want to ask your solar retailer how the Small-scale Technology Certificates (STCs) will be used. Most retailers use these certificates to offer upfront discounts to customers purchasing a solar system.

Speak to your solar retailer or installer about installation timeframes for your solar panels and get it in writing. Make sure you check the detail in your contract, as the fine print may be different to the sales pitch. Also, make sure that all the relevant fields have been filled out in any paperwork you are given.

Be aware that once your panels are installed, there will still be a number of steps to complete before you can connect to the electricity grid and receive a feed-in tariff.

Questions to ask:

  • When will my solar panels be installed and where is this stated on my contract?
  • Has the price of my system been reduced by the value of Small-Scale Technology Certificates (STCs)?2
  • Has the dollar value of these been included in my STC Assignment Form?
  • Do I need to leave a deposit and can I get a refund if I change my mind?

Solar PV systems should generally have a long lifespan, but be wary of inflated claims. Be sure to ask your solar retailer about efficiency levels, plus whether the warranty periods are different for the solar panels and the inverter.

Some solar retailers might also promote a larger inverter as part of a package – for example, you might be offered a 3kW inverter for 1.5kW solar panels. Your system will not generate any extra electricity with a larger inverter, and in some cases a large inverter may actually reduce the amount of electricity fed back to the grid.

Questions to ask:

  • What are the warranty periods on the solar panels and inverter, and who can I contact for service?
  • Can I see performance curves for my combination of panels and inverter?

To feed your excess electricity back to the grid and ultimately save money, you will need to have a solar capable meter installed to measure your electricity exports at regular intervals.

Be sure to ask your electricity retailer about any changes to your electricity rates before you purchase your solar system to ensure you have all the right information.

Questions to ask:

  • Will I need to change or reconfigure my meter, and is there an additional cost?
  • Will there be any resulting changes to my electricity rates or plan as a result of changing my meter?

Individual solar panel designers and/or installers are CEC accredited, not solar retail businesses. So, while a solar retailer might be a CEC member, they may or may not use accredited designers and installers.

To be eligible for STCs your system needs to be signed off by a CEC accredited designer and installer. CEC accredited designers and installers are now required to have accreditation numbers and carry photo ID which you should ask to see and note down. You can also ask to see their business references.  Check the following website for a listing of accredited installers:

Questions to ask:

  • Do you use CEC accredited designers and installers?
  • Can I check their accreditation number and photo ID?

What next?

As long as you do your homework, compare quotes and ask the right questions, you should be ready to start saving money on your electricity bills and reducing your carbon footprint by installing solar panels.

Make sure you ask for a full written quotation and contract before signing up, including:

  • The total price of the system
  • Proposed start and completion dates
  • Specifications including quantity, size and output of the solar PV panels as well as the inverter specifications
  • An estimate of the average daily and annual electricity output of the system
  • Estimated production in the best and worst months of the year
  • Warranties and guarantees
  • The responsibilities of the respective parties, such as the solar panel retailer and installer, your electricity retailer etc.

Who to contact if you have a problem

If you need to lodge a complaint in relation to marketing practices undertaken by a solar PV retailer, you can contact Consumer Affairs Victoria:

Consumer Affairs Victoria
1300 55 8181

1 Clean Energy Council: 'Consumer guide to buying household solar panels'

Page last updated: 09/06/17