Australia: PV safety issues highlighted

The Australian PV Association (APVA) held a National Online Seminar last Friday, February 18, which allowed experts to field questions from consumers and practitioners about a variety of safety issues currently facing the PV industry in the country.

It was organized after a series of PV installation compliance inspections, carried out during late 2010 and early 2011 by the Office of the Renewable Energy Regulator and the Commonwealth Department of Climate Change and Energy Efficiency in Australia, discovered a number of recurring PV issues, which led to a significant number of PV systems being disconnected from the grid.

The webinarÂ’s main focus was on how companies can best meet forthcoming standards, prevent house fire, wind damage and related risks, pass government inspections, avoid loss of ability to create Renewable Energy Certificates and avoid loss of accreditation.

Ted Spooner, a Visiting Fellow in the School of Electrical Engineering and Telecommunications at the UNSW, was one of the experts fielding questions on the day. He tells pv magazine about some of the issues raised at the event: "One of the themes that did recur anecdotally is the installation of polarise d.c. circuit breakers being wired incorrectly. This is a fire hazard and we are moving to change the standard to require only non-polarised because of the mistakes being made."

He continues: "I think the other issue that will probably come out is simply wiring protection and support of the PV module wiring behind the arrays. One thing that is of absolute importance for the industry are concerns of fire fighters and emergency service workers with PV wiring after a fire and that is still the subject of international workshops and there is not a clear solution to this at present.

Spooner adds that other concerns related to earthing practices, which are going through a legal rethink in the country at the moment. He explains: "The most detailed questions were about earthing practices and reasons for earthing and a few on proper voltage ratings of circuit-breakers."

The PV Industry is closely examining standards in the development of new requirements, says Spooner, and is preempting some of the most important releases by announcing changes to industry guidelines progressively. The Clean Energy Council (CEC) has been slowly releasing these changes recently, which include alterations to the AS 4777 Grid connection of energy systems via inverters and the AS/NZS 5033 Installation of PV arrays.

Some installers are still trying to adapt to the new regulations, which stipulate that in PV systems that operate above 120V d.c., all module frames shall be earthed in such a way that if one module is removed no other componentÂ’s earth is compromised. This is particularly important for non-isolated inverters, but is also important for all PV systems operating above 120V d.c.

"Safety is absolute priority and this is the primary focus of standards and electrical regulators," continues Spooner. "There are many new developments coming. We also expect new standards coming for inverter equipment and revisions of standards for installation, which is confusing some.

"Internationally there is a lot of new work on new system equipment offering potential improvements in safety and performance, but there will be some time before it is proven technology in the marketplace."

Spooner was pleased with what happened and said the online seminar structure "worked well" and the fully revised AS/NZS 5033 is expected mid-year. The event attracted 23 live participants and a further 62 have booked to receive a recording of the event. "It was I think useful and it will be interesting to look at the feedback when we get it all in," he says, adding, "The most common questions were related to installation practice and standards."

Natural disaster aftermath

The webinar was made all the more relevant following the floods and cyclone that wreaked havoc in the state of Queensland earlier this year, and Spooner says that conversations surrounding PV installations in the disaster-struck state of seemed to be quite positive.

He concludes: "The feedback that we are aware of relating to PV installs in Cairns and other places affected by the cyclone and flooding appears to be that the systems survived very well. As with any electrical system after floods and major events, there is a need for thorough expert examination before re-commissioning."