The Clean Energy Regulator's inspection scheme has not found any rooftop solar panel systems in the ACT to be unsafe for nearly five years, but it has inspected just 1 per cent of the systems installed in the territory.
Data from the regulator shows that 223 rooftop solar panel systems were inspected in the ACT between the start of the inspection scheme in 2011 and July 31 this year.
Nine systems were classified as unsafe, with each of those inspected before January 31, 2014.
Despite this, the ACT's percentage of unsafe systems remains above the national average, with 4 per cent of the Canberra systems inspected assessed as unsafe, compared to the national average of 3.4 per cent.
An unsafe system is defined by the Clean Energy Regulator as being a severe risk. Examples include systems with exposed live wiring, unsecured rooftop panels or water entering the DC isolator box and creating an electrical safety risk.
According to data released by the Clean Energy Regulator and consultancy SunWiz earlier this month, 15 per cent of territory homes – 22,120 in total – have rooftop solar panels. This means just 1 per cent of the systems installed in the territory have been inspected by the regulator.
Solar panel systems have been responsible for at least two fires in the ACT this year – one in Amaroo in February and another in Denman Prospect in October. The Denman Prospect blaze, caused by a component stored in a garage but used to power a rooftop system, prompted neighbours to express fears that their homes could also burn.
Since 2011, the Clean Energy Regulator has found 25 solar panel systems in the ACT to be substandard, meaning they were a high risk and rectification was required. While 11.2 per cent of the Canberra systems tested were considered substandard, the national average for that classification was 17.7 per cent.
Federal Energy Minister Angus Taylor expressed his concern about faulty solar panel systems this week, writing to state and territory government ministers in the wake of a national audit of the Renewable Energy Target.
The audit found between 21.7 per cent and 25.7 per cent of rooftop solar installations inspected across Australia between 2011 and mid-2018 were rated either unsafe or substandard each year, except in 2012 and 2013.
In his letter, Mr Taylor wrote that 20 per cent annual growth in rooftop solar uptake and 50 per cent capacity growth would attract new, inexperienced electricians and perhaps "lower quality suppliers and unscrupulous operators" to the industry.
"I encourage you to consider the potential risks associated with the rapid growth of rooftop solar PV in your jurisdiction, and to take appropriate action to ensure safety and consumer risks are managed appropriately," Mr Taylor said in the letter.
ACT Climate Change and Sustainability Minister Shane Rattenbury said the ACT government audited rooftop solar panel systems at the time of installation, with the Clean Energy Regulator audits conducted 12-18 months after installation.
"If the systems aren't maintained, then it's likely the Clean Energy Regulator would pick this up in its audit," Mr Rattenbury said.
"It's through this dual process that any unsafe units are detected and rectified to ensure the safety of the community."
Mr Rattenbury, who is also the ACT's Consumer Affairs Minister, said anyone concerned about the safety of their rooftop solar panel system should have it checked by a qualified electrician.