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Mercury Solar - FAQS

 

With solar panels you can turn sunlight into electricity. This electricity can be used in your home, stored in a battery or exported back to the grid. This export can then be purchased by retailers like Mercury. This is known as distributed generation, import/export, Buy-Back or embedded generation. See how solar works here.

 

Online Solar Estimation Tool

 

The online Solar tool is a wonderful way for you to see approximately how much a Mercury Solar solution could save you and could cost to install. Give it a go here.

 

This tool uses the info you provide where possible but also relies on factors, including:
- If we don’t have your annual usage data, the consumption profile of the average Mercury customer (not for you specifically).
- Levels of solar generation using the average sun exposure in different regions.
- Mercury’s pricing for each network region (including network costs).
- Solar generation and consumption are based on average hourly data and only an estimate.

Additional factors will influence how much you’ll save with Mercury Solar. These include, but aren’t limited to, the angle of your roof, the direction your house faces, shade, the number of panels you choose to install, actual buy-back rates and retail tariffs, how much power you use as well as when you use it and, of course, the weather. While the calculation takes these into account, it is only an estimate and isn’t a guarantee of the amount you could save.

If your usage changes, as your household changes, this will also affect what you could save with solar. For example, your usage could increase and mean that you can get even more out of your Mercury Solar system. Wonderful!

The calculation is used to make a recommendation for the Mercury Solar package that’s right for you and to estimate the potential benefits that you might have with solar. The Mercury Solar package you purchase is your decision. However, we believe this tool is a great way of helping you make an informed decision.

Prices are GST inclusive for the supply and installation of equipment.

 

The Solar Calculator tool uses the information you provided with some assumptions (please see the FAQ for “How do you work out how much I can save with Mercury Solar?” for details) to estimate how many panels is best suited for you.

It’s an estimation and when a solar expert does a free on-site, no-obligation quote, they will be able to confirm the Mercury Solar solution that is best for your house.

 

The Solar Calculator uses the estimated amount of energy generated by the recommended solar system per year, the average amount of carbon produced per unit (aka kWh) of commercially generated energy from the Environment 2019 report 'Measuring Emissions: A Guide for Organisations' and the amount of CO2 absorbed by 1m2 of native NZ forest.

 

The Solar Calculator uses the estimated decrease in your energy usage and the amount of carbon footprint for the average NZ household’s energy from the Motu working paper 'Greenhouse Gas Emissions in New Zealand: A Preliminary Consumption-Based Analysis' to work out the decrease in percentage.

For the number of kilograms less, the Solar Calculator uses the estimated energy generated by the recommended solar system per year and the average amount of carbon produced per unit (aka kWh) of commercially generated energy from the Environment 2019 report 'Measuring Emissions: A Guide for Organisations'.

 

The Solar Calculator uses how many kilometres you can travel in a 2019 40kWh Nissan Leaf, as well as its battery size (40kWh) and the estimated energy generated by the recommended solar system.

 

When you enter your property address into the Solar Calculator, we can use Google Maps to show you a bird’s eye view of the property.

 

It’s an estimation based on the information you supplied about your house and how you use power as well as a few assumptions (please see the FAQ for “How do you work out how much I can save with Mercury Solar?” for details).

This calculation is used to make a recommendation for the Mercury Solar package that’s right for you and to estimate the potential benefits that you might have with solar. The Solar Calculator is a snap shot of what Mercury Solar could do for you.

When a solar expert does a free on-site, no-obligation quote, they will be able to provide a more detailed quote that is specific to your house.

The Mercury Solar package you purchase is your decision. However, we believe this tool is a great way of helping you make an informed decision.

Importing and Exporting Power

 

The cost of having an import/export meter installed and to have the ability to export electricity back to the grid is currently $99, $300 or $747.50 (dependent on meter size) incl. GST.

 

You must have written approval from your lines company, to be able to export power from your property onto their network. You can find your lines company contact details here

 

Once approval has been given by your lines company to export power from your property, email our connections team along with the attached meter installation application and lines company approval to ConnCentre@mercury.co.nz.

 

Any power exported will currently be bought off you at a rate of 8 cents per unit. (Subject to change). (Excluding GST and discounts). Mercury Solar customers on the Vector network will get a rate of 12 cents per unit and Counties Network customers will receive a rate of 10.89 cents per unit.

 

Available nationwide, with the exception of two networks; Network Waitaki & The Lines Company.

 

The Buy-Back rates will be applied from when the Buy-Back meter is installed. We are unable to calculate the Buy-Back prior to the meter being installed.

 

Mercury is required to apply GST to its taxable supplies, in your case this is the electricity Mercury has supplied to you.  The electricity that you have generated is considered for tax purposes to be a supply from you to Mercury.  GST can only be applied to the value of this if it is a taxable supply under the Goods and Service Tax Act 1985.  In most cases this will only be applicable if the supplier is GST registered, and the property and equipment used to generate the electricity are business assets.  If you feel this applies to your situation we suggest details be passed on for further review. 
 

Other information you might find useful:

If you are in a contract with Mercury, once your import/export meter is installed your contract will end, and no termination fees will be charged.

If you have any more questions feel free to contact us on 0800 10 18 10, our Call Centre is open Monday to Friday from 8am until 8pm, or email us anytime at Solar@Mercury.co.nz and we’ll get back to you as soon as we can.

 

 

Metering

 

This is a meter with two registers, one to record the import usage from the network and one to record the export usage to the network. These are also known as Buy-Back or 2-way meters.

 

In order for us to record your usage and output, you’ll need to install an import export meter.

 

You will need to get the network company’s approval before doing this.

Once you have received the network's approval we can install the meter and then you can arrange to have the panels installed. To get the meter installed you will need to email our connections team along with the attached meter installation application and lines company approval to ConnCentre@mercury.co.nz.
 

 

You will not receive any credit for any generation as we will be unable to calculate this. There may also be an impact on your usage.

 

Yes, but Mercury will read the meter manually and the readings will not be available in the Usage section of My Account.

 

Your current smart meter is not configured to record the export usage.

 

If the system is capable of generating excess power to the grid then you must have a Buy-Back meter installed. This is industry regulation.

 

Solar Usage Monitor

 

The Solar usage monitor helps you monitor your Mercury Solar system and provides insights into how much energy you’re generating, consuming and exporting. It also shows you estimated savings you’ve made since having a solar system installed, how much you’ve earned from exporting power and what you’ve spent on importing power from the grid.
By installing and using the Solar usage monitor you can see exactly how your solar energy system is performing in near real time (live 30 second data).

 

It connects easily to your solar energy system through your electricity distribution board. The solar usage monitor will organise one of our specially trained installers to come to you.

Once installed, it uses patented algorithms in combination with a number of benchmarks including live local weather data and manufacturer specifics on your solar energy system’s model and location. This information is then fed into your personalised Dashboard which you can access 24/7 from your computer, tablet or smart phone.

 

 

As part of your Mercury Solar 3 year contract we will include access to the solar usage monitor. This will be installed by a trained electrician.

 

It is compatible with all solar energy systems and inverters, whatever their age.

 

This tool (as part of Solar Analytics monitoring service) is an advanced analytics based system that is only offered by Mercury Solar. 

Our patented algorithms measure against a number of benchmarks, including your local weather data which many other monitoring systems fail to account for.

 

We welcome your feedback. You can contact us with your comment or suggestions for improvement by calling 0800 MSOLAR or emailing us at solar@mercury.co.nz

 

Unfortunately you will lose access to the solar usage monitor tool if you leave Mercury as it is only available as part of the Mercury Solar offering.

 

Common Faults

 

Solar production data must be transmitted from the monitor to the solar usage monitor tool; this is done via the mobile 3G connection. If a ‘Communications fault’ occurs, it means the monitor cannot transmit your production data so cannot be displayed on your solar usage monitor dashboard. The monitor continues to collect data for two weeks, but it cannot be displayed in your dashboard until the problem is fixed.

The communications fault can usually be rectified by restarting the Wi-Fi or 3G connection. Sometimes it is necessary to reconfigure the monitor.

Once communication is re-established, the missing data will be transmitted and displayed on your solar usage monitor dashboard.

In the event of a Communications fault, your solar usage monitor will notify you via email and the dashboard to advise you of the recommended course of action to resolve the fault.

 

Communications fault
Wi-Fi, 3G or other communications fault.

Solar usage monitor incorrect wiring
The solar usage monitor has been connected incorrectly.
 
Incorrect site configuration              
The site configuration (number of inverters, panels, tilt, orientation etc) has been entered incorrectly in the solar usage monitor registration process.
 
Incorrect CT connection
The CT, which is connected to the solar usage monitor and measures the energy produced by the system, has been clipped onto the wrong cable or clipped incorrectly.

 

 

Shade

The solar PV system is shaded by trees or roof obstructions resulting in lower than expected performance.

Low insulation resistance

The insulation in the solar PV system has decreased due to water ingress or there is leakage of current from the solar panels through an incorrect path. Also known as low riso

Mismatch

If the solar panels in the system have different performance profiles the whole electrically connected row of solar panels will have the current of the lowest performing panel in the system. This can lead to hotspot.

Phase imbalance

the current or voltage produced by the inverter is not consistent across various phases (segments) of the system.

Power factor issues

The current and voltage produced by the inverter are not consistent with one another.

Cable disconnection

The cable connections in the system have lost contact due to a damaged or loose connection.

Plug failure

The plugs connecting one solar panel to another have disconnected or failed.

String disconnection

An electrically connected group of solar panels has been disconnected due to cable disconnection or a tripped or blown fuse, switch or circuit breaker.

String fuse issue

One or more of the fuses on electrically connected groups of solar panels is faulty or has been turned off, disconnecting a number of solar panels.

DC isolator issue

One or more of the DC switches in the solar array is faulty or has been turned off, disconnecting a number of solar panels.

Clipping

The power produced by the solar PV array is too high for the inverter, so the inverter cannot use all of the power and some is lost as heat.

PV over-voltage

The voltage produced by the solar PV system was too high for the inverter, resulting in inverter shutdown.

Earth fault

The current from the solar panels has taken an incorrect path due to a system defect. This resulted in inverter shutdown. Also known as ground fault, isolation fault.

AC disconnect open

The switch between the inverter and the electricity grid has been turned off, disconnecting the inverter from the electricity grid.

DC disconnect open

The switch between the solar panels and the inverter has been turned off, disconnecting the solar panels from the inverter.

Grid shutdown

The electrical grid that the solar PV system is connected to has shut down, shutting down the inverter.

Cabinet open

the inverter housing has been opened, resulting in inverter shutdown.

Over temperature

The inverter was operating above the rated operational temperature, resulting in inverter shutdown.

Under temperature

The inverter was operating below the rated operational temperature, resulting in inverter shutdown.

Frequency above limit

The frequency of the electrical grid that the system is connected to was too high, resulting in inverter shutdown or export limitation.

Frequency under limit

The frequency of the electrical grid that the system is connected to was too low, resulting in inverter shutdown or export limitation.

AC over-voltage

The voltage of the electrical grid that the system is connected to was too high, resulting in inverter shutdown or export limitation.

AC under-voltage

The voltage of the electrical grid that the system is connected to was too low, resulting in inverter shutdown or export limitation.

Blown String fuse on inverter input

The current flowing from the solar PV system to the inverter was too high, therefore the fuse on the inverter has blown. Inverter memory or communication error There has been an internal memory or communication error in the inverter.

Inverter aging

The inverter has aged and its performance has gradually declined due to vibrations in the core, degradation of electrical components or using the inverter above its rated limits.

Inverter failure

The inverter has failed due to electrical component wear and tear, high temperatures or overuse.

MPPT tracking error

The inverter is not operating at the correct specifications and therefore it is not converting the maximum amount of energy from the solar panels into usable electricity.

 

 

Soiling

Dirt, dust and sand have built up on the top surface of the solar panel.

Glass breakage

The top glass surface of the solar panel has cracked due to heat, wind, hail, vandalism or handling.

Microfractures

The solar panel has obtained very small cracks due to heat, wind or handling. These can be invisible.

PID

Potential Induced Degradation. An unwanted electric field has built up between the solar panel and its metal frame due to heat and humidity, resulting in gradual performance decline.

Hotspot

A large amount of heat has collected in a small area resulting in a burnt or damaged spot on the solar panel. This is mostly due to cracks on the solar panel or shade.

Encapsulant discoloration

The encapsulating layer between the solar panel and the top glass surface has discoloured due to UV radiation and other factors.

Encapsulant corrosion

The encapsulating layer between the solar panel and the top glass surface has corroded due to UV radiation and other factors.

Delamination

The encapsulating layer between the solar panel and the top glass surface has become detached due to water ingress in high humidity conditions.

Deformation and loose frames

The solar panel has deformed or its metal frame has loosened due to handling damage.

Bypass diode failure

One of the electrical components of a solar panel (the bypass diode) has failed due to heat, lightning or other factors.

Gradual degradation

All solar panels gradually degrade due to water corrosion, natural degradation of metals, and harsh sunlight.

Module open circuits

Electrical connections within the solar panel have lost their necessary contact due to cracks or deformation from hail, heat or other forces.

Module short circuits

Metals within the solar panel have come into contact and are conducting electricity incorrectly, due to weathering, cracking or electrical corrosion.

Junction box defect

The small black box on the back of the solar panel which houses electrical components has been damaged due to heat, lightning or water vapour.

 

 

Other questions

 

No. Our standard solar rates will apply from when the new meter is installed. If  you are on a contract a break fee will not be charged.


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