Safety requirement for roof top solar on commercial buildings and unit complexes
This information is for commercial property owners and body corporates, including their appointed managers.
Solar PV installations with a combined inverter capacity over 30 Kilowatts require a grid protection system installed to comply with Australian Standards and Northern Territory legislation.
What is a grid protection system?
A grid protection system is installed between the solar PV installation and the power grid to maintain safety of the system and stability of the power grid. These systems are installed where the power grid connects to the commercial building or the unit complex.
The grid protection system works in addition to the safety function of individual inverters by disconnecting all of the solar PV’s within the installation from the grid when there is a blackout or major voltage or frequency fluctuations. This function prevents the solar PV’s within the complex from forming its own grid and generating electricity which can be fed back into the power grid endangering maintenance and line workers and possibly the general public.
A variety of manufacturers can provide different solutions to achieve this.
When is a grid protection system required?
A grid protection system is required when the total solar PV capacity connected to a single grid connection point exceeds 30 Kilowatts. The following two examples require a grid protection system installed.
What do you need to do to comply?
Commercial property owners and the body corporate of unit complexes have an obligation to ensure the electrical installation in their property complies with the legislated technical and safety requirements.
It is recommended that commercial property owners and body corporates:
- Keep accurate records, including combined capacity, of any existing Solar PV installations on the property.
- Check to see if any additional solar PV installations will increase the property’s total capacity over 30 Kilowatts before approving the installation.
- Contact Power and Water to see if there are any other requirements before the solar PV is installed.
A grid protection system must be installed when solar PV additions increase the property’s total capacity over 30 Kilowatts. Failing to do so is a potential breach of Section 31 of the Electrical Safety Act 2022 by both commercial property owners and body corporates.
If any portion of the property is used for commercial purposes, the property owner or body corporate may also be in breach of Section 26 of the Work Health and Safety (National Uniform Legislation) Act 2011.
A property with total capacity over 30 Kilowatts installed after 30 March 2017 without a grid protection system is considered non-compliant and may be disconnected from the grid by the network operator (e.g. Power and Water).
Further information
The information bulletin Grid protection requirements for Solar PV installations over 30 Kilowatts outlines the compliance requirements for electrical contractors, and the solar industry.
Contact us
For further information please contact the Electrical Safety Unit on 1800 019 115, via email at AGD.NTWSElectricalSafety@nt.gov.au