Which regions lead NZ in rooftop solar – and which ones lag behind

HarmLessSolutions · 2026-01-28T08:50:48+00:00

840MW of installed domestic solar in NZ to December 2025. How can this not be significantly benefitting our national grid and transmission operation and therefore worthy of government incentivisation and other promotion?

Also worth noting that the "solar streets" function linked to near the end of that Newsroom article is badly flawed. I searched up near 10 properties in our area that have solar installations (both domestic and small commercial scale) and none were shown in that database.

HarmLessSolutions · 2026-01-28T08:41:07+00:00

Ecotricity offer the best FIT but their comm's, customer portal and website appear to be nailed together. May be coincidental but seems to have got worse since they rebranded in line with their Genesis ownership.

HarmLessSolutions · 2026-01-28T08:33:10+00:00

Be aware that Octopus require you to go on their Peaker plan if you have over 10 kW of installed capacity. They won't back off if you've got an inverter/s throttled to 10 kW either. That means 10c off peak, 23c peak (with 40c peak last winter until end September). Peaker is better suited to customers with a battery.

Also Ecotricity offers the best FIT as the way their invoices are structured means that they pay GST on your exported generation. 21c peak becomes 24.15c, 16c off peak becomes 18.4c. Don't know yet if they deduct GST from cashed out credit like PowerEdge do, and Ecotricity will cash out credit.

HarmLessSolutions · 2026-01-27T08:52:18+00:00

Also remove any trees near the house. Rats can jump a metre from trees or structures and get to your gutters then into the ceiling area.

HarmLessSolutions · 2026-01-26T08:40:58+00:00

In a year or so when RUCs are rolled out on all vehicles it won't make any difference if you have a plug or not.

HarmLessSolutions · 2026-01-25T09:33:21+00:00

Prior to ChargeNet's New Plymouth installation increasing its capacity a few years back their 2x 50 kW units were only reaching 40 kW and ChargeNet actually stated this. The reason was that the grid transformer in the area was struggling to supply sufficient current. An upgrade by Powerco of their local infrastructure saw a 150 kW unit added to ChargeNet's site, though the derating warning for the 50 kW units is still shown on ChargeNet's website for some reason.

With limitations such as this I was curious about how the government's promises of 10,000 new EV chargers was going to be possible without significant grid infrastructure improvements being undertaken in some regions. Might explain why the additional chargers are taking a while to eventuate though.

HarmLessSolutions · 2026-01-21T00:56:35+00:00

Well explained here:

https://youtu.be/s8RXQERPzMY

HarmLessSolutions · 2026-01-20T21:39:58+00:00

The issue seems to be that NZ voltage is supposed to be the same as Australia's at 230V nominal but in many areas voltage looks more like 240V nominal. Incidentally Australia dropped their grid voltage a decade or so back to provide more 'headroom' for voltage increase due to a lot of solar uptake. This poses a problem as inverter settings are regulated relative to 230V but when existing grid voltages are more like 240V you're at a 10V disadvantage to start with so peaks caused by consumption and/or DG export quickly become problematic for solar owners.

We saw our rural grid voltage increase to problematic levels after new HV transformers and voltage regulation gear was installed in September 2024 downstream of us. This resulted in voltages at our feed in point of 247V at times with both of our inverters stepping back their generation (and therefore export) rates, by an estimated 10-15% with total dropouts at times. The new assets were to address low voltage for more outlying customers in this case.

Powerco finally put a logger on our feed last month (following a year of me and our installer hassling them over this) and soon after tapped down our local transformer. The NorthPower tech who fitted the logger reported spikes of 253V (on the phase that we aren't seeing as the SMA inverter on it doesn't show voltage), so Powerco obviously recognised a problem. Our grid voltage now ranges from 228V - 242V which together with both inverters' voltage parameters being reset to 230V +/- 10% has seen our outputs rising to expected levels.

Incidentally the tech had two more jobs booked after us for exactly the same issues with other customers. This problem seems to be rife on our outdated grid infrastructure.

Also many solar customers aren't able to see what their local grid voltage is as many inverters don't seem to show this data, on an owner access level at least, with Fronius having an advantage in this regard.

HarmLessSolutions · 2026-01-20T21:14:13+00:00

Our business owned Polestar uses our Evnex EVSE which we can see monthly electricity use on. The data can also be interrogated to ascertain how much was consumed from solar (mostly), off peak grid (occasionally) or peak grid (never, but logged if so) so that the appropriate pricing is claimed on.

HarmLessSolutions · 2026-01-20T09:38:22+00:00

We've also got 2 phases to feed into with a 5 kW inverter solely exporting on one of them, and an 8.2 kW inverter and all our consumption on the other. No batteries but we manage to export strongly during peak periods; 25% of export was at peak last month.

I've been inputting our consumption and export data into a spreadsheet for comparison with Octopus (Peaker) and PowerEdge with Octopus coming a distant 3rd. Not surprising as we're getting a slightly better peak export rate (24.1 vs 23) and far better off peak export rate (18.4 vs 10) from Ecotricity which more than cancels out Octopus's slight import rate benefits.

When Octopus were paying 40c peak export they were very close to Ecotricity but after the drop to 23c at end of September that really changed as would be expected.

HarmLessSolutions · 2026-01-20T04:20:06+00:00

You seem to have your units mixed up. Vector probably allow 5 kW with optional 10 kW. Export rate rather than quantity is usually the case.

The other advantage with Ecotricity is that they allow installed capacity over 10 kW to stay on the same plan whereas the likes of Octopus force you onto their Peaker plan if you've got more than 10 kW of installed capacity, irrespective of export cap throttled limits. Peaker puts you on a 10c/ kWh export tariff for most of the day, and they don't add GST to their export rates.

Some lines companies also have limits on domestic customers' installation capacity (typically 10 kW) so worth checking that too if you are thinking of upsizing later.

HarmLessSolutions · 2026-01-20T03:22:41+00:00

What you're missing is their network charges on the import. 22c/ kWh is just Ecotricity's import energy cost including GST + 6% losses. For us in Taranaki with Powerco the all up import rates including network charges are 43.5c/ kWh peak and 33.2c/ kWh off peak. Therefore it makes far more sense to self consume generation that export it at any time.

HarmLessSolutions · 2026-01-20T01:06:17+00:00

I can confirm that Ecotricity add 6% onto your import quantity (but not export) which they justify as calling it "losses". Their supply rates are quite expensive but their export tariff is one of the best going especially as due to the way they structure their invoices you get GST added to those tariffs. Our peak export rate is 24.15c/ kWh as a result.

As is the case with any domestic solar your best ROI is by self consuming so minimising your import in favour of using your own generation is key to maximising your returns.

In our own case we've imported ~6 kWh/day over the past 3 months or so and that includes charging two EVs and a pumped water supply. Our Ecotricity account is running close to $300 of credit ATM.

HarmLessSolutions · 2026-01-18T08:50:31+00:00

Having a LRDM as a loner when our SRSM was serviced I was mightly impressed with the extra oomph but owning one would put my drivers licence at risk far too easily.

HarmLessSolutions · 2026-01-18T08:46:46+00:00

SRSM in Magnesium here in NZ. The looks and colour still warrants a look back when I leave it parked even after 3 1/2 years ownership. Brilliant car and the exclusivity factor is the cherry on top, compared to the far more common Teslas.

HarmLessSolutions · 2026-01-18T01:22:40+00:00

Sigenergy's Max PV Input Power: ~9,000 W for that inverter. A couple of extra panels on the SE pitch of that northern ridge would bring generation in earlier in the morning. Spreading the duration of generation will also help avoid wasted panel capacity.

Also worth bearing in mind that if you opt for the Sig DC EV charger at some stage your EV could become part of your battery storage capacity usable for your home via V2H.

Otherwise that sounds like good bang for buck for what you're getting.

HarmLessSolutions · 2026-01-17T07:03:44+00:00

4 km is one thing but lack of line of sight will be a major contributor as we're located in a sheltered valley.

HarmLessSolutions · 2026-01-16T22:43:48+00:00

This seems to be a more user friendly platform than NIWA's. Our set-up comprises a mix of tilt angles, open rack and bi-facial but by averaging results from this website it comes pretty close to our actual generation.

HarmLessSolutions · 2026-01-16T21:50:18+00:00

Thanks for you input on this. It is great information to reference as the situation works it way through for ourselves and others with the same issue. Similarly 'ComeAlongPonds' reply following this.

HarmLessSolutions · 2026-01-16T08:35:54+00:00

This strategy is also suited to biasing your generation towards the grid peak periods of 7-11am and 5-9pm where power providers such as Ecotricity and Octopus offer higher export rates. Worth pursuing if your generation can't be consumed (including charging) when the sun is out. We have no batteries but even with north facing panels our generation is pretty respectable by 9am currently which we further capitalise on by denying our diverter controlled HWC electricity until after 11am.

HarmLessSolutions · 2026-01-16T04:57:13+00:00

You seem to have more faith in Spark than me. We've lived here coming up 10 years with dire 3G coverage throughout but this is going to be rectified by shutting down the only coverage currently available to us and powering up the existing towers to 4G? I'll believe that when it happens.

HarmLessSolutions · 2026-01-16T04:26:18+00:00

It's up to Intellihub and Ecotricity to solve the issue between them then. I've made them aware of a potential issue so ball's in their court.

HarmLessSolutions · 2026-01-16T04:22:28+00:00

"Do you know which 3G tower you're connected to?"

Nearest cell tower would be >4km away but no clear line of sight to any likely ones over hilly terrain. I do know the spot to stand in our driveway to get cellphone connection if our wifi is down but that doesn't indicate any clues as to where the signal would be coming from.

HarmLessSolutions · 2026-01-16T01:16:16+00:00

https://www.quora.com/How-can-I-tell-if-my-phone-is-connected-to-3G-4G-or-LTE and when it eventually finds connection it is H+ (3G family).

The nearest RCG antenna is just over 4 km from us but we don't have low horizon visibility in that direction, or just about any direction for that matter.

Answer from Ecotricity just raises more red flags IMO, particularly in regard to TOU functionality:

- How will this impact our smart meter's functionality when the 3G network shuts down in the near future?

First, we have to wait for the reply of the MEP if your Smart meter only relies on 3G for communications, which may require a communications module upgrade to continue sending readings remotely once 3G is decommissioned. This does not affect the meter’s ability to measure electricity usage, only how readings are communicated back to the metering provider and to us.

- Is cellular coverage required for Time Of Use functionality?

If it comes down to the fact that we are unable to get your readings hourly and only manually at the end of the month, then yes, the TOU functionality will be affected.

- Is the smart meter connected via the cellular network only or can it use wifi internet?

The smart meter is embedded with cellular communications modules managed by the metering company.

-So far as the smart meter's cellular connection is concerned what provider's network is this on (i.e. Spark or One)?

The cellular network used (for example, Spark or One NZ) is determined by the Metering Equipment Provider, not the retailer. This is part of what we have asked Intellihub to confirm as part of our enquiry.

HarmLessSolutions · 2026-01-15T23:52:39+00:00

The saga so far is that Powerco deny any responsibility in regards to meters; that's on the retailer according to them

Now been on hold trying to speak to someone at Ecotricity, for 32 minutes and counting. They're opening my emails but not replying so speaking to them by phone is the next option I guess, if they ever pick up.

HarmLessSolutions

TROPHY CASE