Class 1 - Small Commercial/Residential PV Systems

Class 1 systems are open to any applicant. This class is pre-approved and there are no export restrictions.

Class limits5kVA Single Phase or 7kVA Three Phase, per lot in all regions.
Sized byPV Inverter (AC sizing).
Maximum inverter size5kVA for Single Phase, 7kVA for Three Phase systems.
EligibilityOpen to any applicant.
Export limitsNo export limiting devices required.
Engineering assessmentNot required, pre-approved.
Power factor requirementsPower factor at site must be > 0.9 at all times.
Battery storage12min ramp down for PV inverter. Max charge rate to be determined by assessment. Batteries are permitted but not compulsory.
TimelineSix weeks total for application processing and meter delivery.
Required arrangements

Class 2 - Small Commercial PV Systems

Class 2 systems are open to any applicant. Applications are pre-approved provided zero-export is achieved at all times.

Class limits30kVA, per lot in all regions.
Sized byPV Inverter (AC).
Maximum inverter size30kVA.
EligibilityOpen to any applicant.
Export limitsZero-Export Limiter Device required.
Engineering assessmentNot required, pre-approved.
Power factor requirementsPower factor at site must be > 0.9 at all times.
Battery storage12min ramp down for PV inverter. Max charge rate is limited by battery inverter (max 10kVA per phase). Batteries are permitted but not compulsory.
TimelineSix weeks total for application processing and meter delivery.
Required agreements

Class 3 - Medium Commercial PV Systems

Class 3 systems are available to commercial customers only. An engineering assessment is required for all applications and an engineering assessment fee is required to be paid upon application. This class may be an exporting or non-exporting connection, pending engineering assessment and customer requests/requirements.

Class limits
  • 200kVA, per lot in Darwin region.
  • 100kVA, per lot in Alice Springs, Katherine and Tennant Creek regions.
Sized byInverter Bank (AC).

Maximum inverter size

  • 200 kVA Darwin region.
  • 100 kVA Alice Springs, Katherine and Tennant Creek regions.
EligibilityRestricted to applicants on a commercial tariff.
Export limitsExport or zero-export permitted pending engineering assessment
Engineering assessmentRequired.
Engineering assessment fee$560 incl GST, non-refundable, payable on application.
Power factor requirementsPower factor at site must be > 0.9 at all times.
Battery Storage12min ramp down for PV inverter. Max charge rate to be determined by assessment.
TimelineSix weeks total for application processing and meter delivery plus six weeks for engineering assessment.

Required agreements

  • Completed and signed Class 3 Application Form
  • Completed and signed copy of the Embedded Generation User Agreement Formal Instrument of Agreement. Available pending engineering assessment.
  • Payment of solar PV fee
  • Technical data such as (go to Technical Requirements for Grid Connection of Photovoltaic Systems via Inverters to see an example of a wiring diagram):
    • wiring diagram
    • switches
    • inverter
    • PV-array
    • metering
    • earthing equipment
    • distribution circuits
    • protection, synchronisation and tripping or equipment interlocks.
  • Your installer must submit to the Connections Officer, Power Networks, Power and Water Corporation, a:
    • Notice of Intention to Work (NIW) on the network
    • Certificate of Compliance
    • Completed and signed copy of the "Embedded Generation User Agreement, Formal Instrument of Agreement" provided following engineering assessment
    • Completed and signed copy of an Embedded Generation Notice provided following engineering assessment.

Class 4 - Large Commercial PV Systems

Class 4 is for large commercial PV systems and requires an engineering assessment. Due to size of systems in this class a more detailed engineering assessment will be required on a quoted basis. Outcomes of the engineering assessment may include increased protection requirements. Class 4 customers must have ramping with level to be assessed.

Eligibility

Restricted to applicants on a commercial tariff.

Export limitsExport or zero-export permitted pending engineering assessment.
Engineering assessment Required.
Engineering assessment fee Quoted basis.
Power factor requirements Power factor at site must be > 0.9 at all times.
Timeline Quoted basis.

Required Agreements
All required agreements will be discussed upon receipt of a formal application letter.

  • Your letter should include:
    • business name and address where you wish to install the Class 4 solar photovoltaic (PV) system
    • a brief summary of the system:
      - approximate inverter bank size (eg. 500kVA)
      - approximate DC Panel arrays (eg. 2 x 250kW)
      - battery control system make & model, proposed method of ramping (minimum 12min with exact amount to be assessed)
      - will be compliant with Australian Standards (AS 4777, AS 3000, etc)
    • your name and contact details.
    • Please address your application letter to:
      The Manager
      Network Development and Planning
      Power and Water Corporation
      GPO Box 3596 Darwin NT 0801
  • Your installer must submit to the Connections Officer, Power Networks, Power and Water Corporation a:
    • Notice of Intention to Work (NIW) on the network
    • Certificate of Compliance
    • Completed and signed copy of the “Embedded Generation User Agreement, Formal Instrument of Agreement” provided following engineering assessment
    • Completed and signed copy of an Embedded Generation Notice provided following engineering assessment.

Zero-Export Limiting Devices

A zero-export limiter is a device that is used to ensure that PV systems will generate as much power as the user requires onsite but not excess energy. Utilities around the world encourage the use of these devices as they reduce adverse impacts within the local distribution network while still allowing users to significantly offset their consumption.

A list of zero-export limiting devices, approved from a technical standpoint as being capable of achieving zero-export by Power and Water is available. Please ensure that any device on the list that offers protective functions can be set to match protection requirements for inverters as specified in Technical Requirements for Grid Connection of Photovoltaic Systems via Inverters.

If you have a zero-export limiter device that is not approved by Power and Water, Power Networks Engineering will review the device. Please complete the Zero-Export Limiter Device Approval form and send to NetworkDevelopandPlanning.PWC@powerwater.com.au

Note: A zero-export limiter is not required for Class 1 systems.

You must have approval from Power and Water Corporation prior to any installation works commencing.

Your installer can help you lodge the application to connect to the electricity network and complete the required agreement. For more information on the class you are applying for see PV class requirements.