Solar installers can prove their worth to customers by applying stringent standards when selecting modules, writes Michelle McCann.

The rooftop PV market is booming, with almost 2GW installed in 2019. In the world of coal-fired power plants, if we call Loy Yang A and Loy Yang B in Victoria a single power station then it is Australia’s largest power plant at 3.2GW. Without combining the Loy Yangs, Australia’s largest coal-fired power plant is Eraring Power Station on the western shore of Lake Macquarie, NSW. It has four “turbo-alternators” and a total capacity of 2.9GW. The rooftop market is a distributed power station on the scale of the largest coal-fired power plants in the country.

We are building one of these large, distributed power stations on our rooftops every year. Whichever way you cut it, the rooftop market is no hobby farm.

As an aside, coal-fired power plants do not have a monopoly on big; the largest PV plant in the world is the Bhadla Solar Park in India, at over 2.2GW (DC). Australia, too, does increasingly large solar plants. Our largest to date is Limondale, near Balranald, NSW, with almost 350MW (DC), and many larger plants are in the planning stages.

But back to the rooftops of Australia. It is not widely known that we lead the world in terms of solar installed per capita, with 600W per person. Our PV systems are cheap and our electricity prices are high, driving these phenomenal rates of deployment. APVI reports that residential solar covers 25% of free-standing homes and more than 70% in some urban areas. With a payback time of 3-5 years being typical, for many customers it’s a question of why wouldn’t you install a PV system?

In this article, I argue that you shouldn’t install a PV system – you should install a good PV system. With such a short payback time, some argue that a cheap system is fine – if you replace it after six years, you still win. Leaving aside the ethics of participating in such a disposable economy, associated questions about true costs and the risks of not making it to six years, I would argue that installers and customers both win more if you install a system that will last, even if your initial payback time is higher. Why wouldn’t you want to win more?


Most PV panels are made from silicon, and silicon over-performs at its job. Silicon and the silicon solar cell at the core of a panel remains the most expensive component by far. It is ironic, then, in that by demanding ever cheaper products we, the market, have pushed manufacturers to cut costs where they can – in the cheap(ish) components that surround our solar cells and protect them from the elements in the outdoors. Saving money on these components reduces longevity.

As we build out our distributed PV power plant on a large scale, every year, what quality checks are we doing before we install a system? Are we checking that it works on an on-going basis? And who is the “we” in this case? The end user? The government? The installer?

Even if some portion of this distributed power plant is supported by government funding, it is unlikely that government will mandate higher-performing, longer-lasting PV panels. You can (and you have the right to) buy a cheap washing machine that won’t last long, and you also have the right to buy a cheap PV system that won’t last long. This leaves our “we” as the end user and the installer. The problem facing both of these groups is getting reliable information about the likely longevity of a system and its initial performance.

Last issue we looked at good procurement processes for a large power plant. We identified five key steps to take: start with the specifications for a good product; check the components are produced well in the factory; conduct spot checks on what arrives in country; keep an eye on things once the farm is up and running and, of course; link all of the above in a tight contract with the manufacturer.

Since we are building a large power plant across the rooftops of Australia, we need a way to transfer these same steps into the rooftop market, acknowledging that the procurement team for our distributed power station is also distributed, around kitchen tables and small businesses across Australia.

At PV Lab Australia, we have tested solar panels used in more than 2GW of power plants across the country and we are very sure it’s possible (and common) to purchase poor product here. It’s also very possible to purchase good product. We are working on presenting a transparent view of what is available on the Australian market on an ongoing basis. In the meantime, there are a lot of things installers can do:

  • Consider taking some quality steps. Do you spot check the performance of the products you install? This will provide a differentiator for you to sell against.
  • If you use a distribution centre, ask what quality steps they are taking. Are they getting product spot checked? If you find an issue, what recourse do they offer?
  • With even moderate volumes it is possible to push manufacturers and suppliers on the contractual terms. Do you have agreed and objectively verifiable performance standards in your purchasing contracts with commercial resolutions pre-agreed if substandard shipments are received?
  • Are you using subcontractors? Does the way you pay them incentivise a quality outcome?
  • Use your nose. If a deal on panels smells too good to be true, it probably is too good to be true, even if you don’t always know why that’s the case.
  • Hold back a small portion of the payment (5-10%) until you are happy with the product and the results of any testing. A supplier that is happy to back their product will welcome this as a differentiator for them in the market.


So, in summary, keep on buying PV, but buy well. From our side, at PV Lab, we’ll make sure we shout about the quality of the Australian market from the rooftops (if there’s space enough left to stand with all those PV systems).

Dr Michelle McCann is a partner at PV Lab Australia and has twice held a world record for high-efficiency solar cells.