Going solar - Frequently asked questions

What Power and Water costs are involved?

The fees required are dependent on the class you are applying for.

All applications will require the solar PV fee to cover the cost of your special metering requirements and a new connection. Your fees may vary depending on your metering point setup and if additional inspections are required, ie the callout of a Power and Water crew to attend your property.

An Engineering Assessment fee is also applicable to:

  • Class 3 - $560 inc. GST
  • Class 4 - on a quoted basis

To review additional fees and charges please view our Pricing and tariff page.

Solar PV fees must be paid when you submit your application documentation.

What buyback rates apply?

For information on the solar PV buyback rate applicable to your installation contact your electricity retailer.

How can I tell if I am on a commercial or residential tariff?

The definition of a commercial and residential customer is defined by your electricity retailer and your tariff. Please contact your electricity retailer prior to installation to confirm your tariff.

I run a home business, can I apply for a Class 2, 3 or 4 PV system?

The definition of a commercial customer is defined by your current tariff. Power and Water will assess your eligibility for a class by the definition provided by your electricity retailer.

Can I change my tariff from residential to commercial?

Please contact your electricity retailer to discuss changing your tariff.

Can I install the solar PV system myself?

No. Solar PV systems must be installed by an accredited solar installer and approval from Power and Water must be obtained prior to any installation works commencing. The panels and inverter must be approved by the Clean Energy Council.

The Building Advisory Committee requires certification of the structural adequacy of the solar PV system.

You should also be aware that solar PV systems are randomly audited by the Clean Energy Regulator and Worksafe NT to make sure that they have been installed correctly and are safe to use.

How much can I save on my electricity bill?

Your savings will depend on the size of the system, location and season. Keep in mind that shade and the system’s position can impact its performance. This electricity then feeds into your local electricity network via the electricity meter. The meter records the amount of electricity produced and this information is used by your electricity retailer to offset your electricity bill.

As a guide, an average Territory home uses 8908kWh per year. The most common solar PV system installed is 5kW, which can produce between 6000 to 9000kWh a year, so as an example, if you install a 5kW system, you could offset almost all consumption for an average domestic user, depending on the system installed. Your solar PV system’s output will vary from season to season.

What size system can I have installed?

Please refer to the PV class system and PV class requirements information.

How long does it take?

Subject to timely provision of documentation, around six to eight weeks in total, however it may take up to a further two weeks in remote communities.

Will the current solar PV policy change?

Power and Water's PV policy and fees are under regular review. From time to time the policy may be refined to take advantage of new technologies and improved processes.

What is a Network Connection Agreement?

The Network Connection Agreement highlights the terms and conditions for the safe connection of your system to the local electricity network. An agreement must be in place for your solar power system to be connected to the network and feed power back into the electricity grid. This agreement enables Power and Water to ensure that your system meets all standards for safety purposes.

Do I need a wiring diagram?

Yes. The wiring diagram will be provided by your supplier or installer. Schematics of the wiring are given in the Technical Requirements for Grid Connection of Photovoltaic Systems via Inverters. This document also sets out other technical requirements the installer must comply with, as well as the ESAA Australian Guidelines.

Why is the size of the system limited?

Power and Water has adopted size limits so that more people can take advantage of the benefits of solar PV in their home, while avoiding adverse effects on neighbouring properties’ electricity supplies. As the popularity of solar PV systems continues, more and more systems are being connected to the distribution network. The network has, until recently, been a ’one way’ transfer of energy. As more PV systems are connected, this could lead to voltage rise at the local level. If unchecked it could lead to voltage rise above the Australian Standards.

What is a Power Purchase Agreement?

The Power Purchase Agreement is an agreement between you and your electricity retailer for the purchase of electricity generated by your solar PV system to enable correct metering and billing standards to apply.

Can I offset the initial investment in a solar PV system?

You can offset your investment by selling your Small-Scale Technology Certificates (STCs) to Power and Water or any other person registered with the Office of the Renewable Energy Regulator. One STC is equal to 1 megawatt-hour (1000 kilowatt-hours) of electricity produced by small generation units unless a Solar Credits multiplier applies, see the Small Generation Unit STC Calculator. STCs are sold in an open market so the price can vary. Power and Water's STC price is determined by current market conditions. Power and Water will pay the market price at the time you apply to sell us your STCs. Under the Federal Government's Solar Credits Scheme, the number of STCs for a home solar PV system is subject to a multiplier. Your installer may also offer to purchase your STCs at the time of installation.

Will the solar system always be connected to the network grid?

The system may be disconnected at any time due to safety reasons. Details are in the Technical Requirements for Grid Connection of Photovoltaic Systems via Inverters.

Why does the system switch off during power outages?

Your solar PV system has a safety switch, which is a device fitted to protect you, your family or business when an electrical fault occurs. The solar PV system will restart when mains power is restored.

Why is my inverter turning off?

Some people may experience their inverter switching off due to high voltages when their PV system has high output, this may especially be the case in rural areas or where PV systems have been oversized for existing service lines. Some new inverters meeting the AS4777.2-2015 standard may have “Volt-Watt response mode” which allows the PV system to moderate its output when the voltage starts increasing.

Settings are to be adjusted where the inverter will maintain full output until the voltage seen by the inverter reaches a setpoint, after which it will ramp down to zero output at 253V (same as the current cut off point).

It is recommended that you check with your installer regarding the capability of your inverter if you are unsure.

Can I upgrade my system?

System Upgrades need to go through the application process as if it were a new system.

For more information contact our Customer Connections Office through the Customer Service Centre on 1800 245 092.

Do new property owners need to negotiate a new agreement for an existing system?

Yes. If a property is sold the existing Network Connection Agreement will become null and void. It is the responsibility of the new owners to contact Power and Water and set up a new Network Connection Agreement. If the property is rented to new tenants, the Network Connection Agreement remains valid, if signed by the owner of the property. New owners and occupiers should contact their electricity retailer for information on Power Purchase Agreements.

Why does the system installation need to comply with the NT Building Act?

When a solar PV system is installed on your roof, modifications are completed according to your roof’s structure. These modifications must comply with the standards listed in the NT Building Act ensuring the continued safety of your building. See the Department of Lands, Planning and the Environment’s website for more information.

Where do I submit my application?

Completed applications can be lodged at any Power and Water Customer Service Centre or in Darwin at the Power and Water One Stop Shop, Ben Hammond Complex, Iliffe Street, Stuart Park.  Alternatively the application can be posted, with a cheque for the PV fee made payable to Power and Water Corporation.

Will I lose my pension concession rebate?

Power and Water administers Pensioner and Carer concessions for electricity, water and sewerage services on behalf of the Department of Health. Queries should be forwarded to the Department of Health on 1800 421 887.

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