Standard for Small IES connections FAQs
All Small Inverter Energy System (IES) connections have the obligation to meet the requirements of our connection standard STNW1170 Standard for Small IES Connections (PDF 1.2 mb). Small IES connections include all inverter based generating system connections rated up to an including 30 kVA.
Answers to frequently asked questions on STNW1170 Standard for Small IES Connections can be seen below.
Who's an accredited person?
An accredited person is a person accredited to the Clean Energy Council to design and/or install renewable energy systems. Categories of accredited persons include:
In all instances, a person authorised under the Queensland Electrical Safety Act (2002) is required to certify the installation.
How does the Standard allow for battery Energy Storage Systems (ESS)?
The standard has been developed to ensure safe and stable operation of the Small IES units at a premises. All battery Energy Storage Systems (ESS) installed at a premises and connected to the electricity grid must have a connection agreement.
Refer to Section 4.4.1 of STNW1170 (PDF 1.2 mb) for the detailed requirements for the installation and connection of ESS.
What is a basic connection offer?
A basic connection offer (otherwise known as a Model Standing Offer) is defined under our Network Connection Policy (PDF 700.2 kb).
A basic connection offer will essentially apply to connections that:
- have capacity available i.e. there is a line available and the network assets in that area have sufficient rated capacity to support the connection
- have generation balanced across phases
- have a rated inverter capacity and export that does not exceed the specified maximum size (as limited based on the connection type e.g. main grid, SWER) and the number of phases.
Where the above criteria are not met, the negotiated connection process will need to be followed to enable a connection for that customer.
When is a Technical Study required?
A technical study is required to:
- determine the relevant safety and technical requirements that will form part of the connection offer
- enable the connection of all negotiated connections.
A technical study is not required for a connection that meets the requirement for a Model Standing Offer and STNW1170 Standard for Small IES Connections (PDF 1.2 mb).
What rules apply for the aggregation of micro-inverters?
The aggregation of micro-inverters (or small-scale inverters associated with individual panels) are subject to the same rules and conditions as any other IES.
What are the power quality response modes?
Inverters must be set with volt–watt and volt–var response modes both enabled. Settings are found in STNW1170 Standard for Small IES Connections (PDF 1.2 mb) and are also available from Energy Networks Australia’s Power Quality Response Mode Settings document.
Failure to comply with these requirements can result in dangerous internal voltages, as well as contributing to voltages above statutory limits on the distribution network.
Where it is detected that incorrect power quality response modes have been set, an installer or person can be reported to the Electrical Safety Office and/or Clean Energy Council for non-compliance. It can also result in disconnection of the premises.
How do I prevent internal voltage issues?
Customers (or their representatives) must ensure that operation of the inverter doesn't cause a voltage rise of more than 2% between the inverter and network coupling point. This has been an issue particularly with larger single-phase systems on rural and acreage blocks. Problems have occurred with these systems disconnecting due to the overvoltage setting on the inverter.