The Complete Guide to Solar Buy-Back Rates in New Zealand

Bottom line up front: A solar buy-back rate is the price a NZ electricity retailer pays you for the surplus solar power your home exports to the grid. As of 2024-2025, those rates range from around 7 cents per kWh on basic flat plans up to roughly 17 cents per kWh on premium or dynamic plans, with peak-window export prices on dynamic tariffs occasionally spiking far higher. The most profitable approach is almost never about chasing the highest headline number. It is about matching the right tariff structure to how your household actually uses power, and shifting consumption (dishwasher, EV, hot water) to make the maths work in your favour. This pillar is the hub for everything we publish on the topic; the cluster articles below go deep on each retailer and each strategy.

Welcome to the Tariffs and Retailers silo. If the Ultimate Guide is the front door of the shop, this is the room where we sit down with a coffee and work out the part that genuinely separates a good solar investment from a mediocre one in Aotearoa: what happens to the power you don't use yourself. Solar panels are the easy decision. The retailer plan you sign with afterwards is the one most homeowners get wrong, and it is the one nobody at the point of sale is incentivised to talk about honestly.

Our job here is to walk you through it slowly, show you the numbers from real NZ retailers, and point you at the right cluster article when you want to go deeper. No jargon for the sake of it. No pretending one plan suits every household. Just the working, the trade-offs, and the traps.

What a Solar Buy-Back Rate Actually Is in the NZ Context

When your rooftop array generates more electricity than your home is using in any given moment, the surplus flows out through your meter and onto the local lines network. Your retailer pays you a buy-back rate for those exported kilowatt-hours. The rate is set by the retailer, not the regulator, and it varies from one company to the next.

This matters because New Zealand has no national mandated buy-back scheme. There is no government-set minimum export price. The Electricity Authority sets the rules of the market, but the price you actually get is a commercial decision between you and your chosen retailer.

That is good news and bad news. Good, because there is genuine competition and a homeowner who shops around can do significantly better than someone who simply signs whatever their installer puts in front of them. Bad, because the headline rates can be misleading; some of the best-paying plans on export come paired with the worst-priced power on import, and vice versa.

Self-consumption is worth more than export, usually

Here is the single most important concept in this entire silo, and it is one almost every sales rep glosses over.

The retail price you pay for a unit of electricity from the grid (your import rate) is almost always higher than the buy-back rate you receive for sending one back. In NZ, typical residential import rates sit between 28 and 40 cents per kWh once GST and lines charges are blended in. Buy-back rates, as noted, sit between roughly 7 and 17 cents per kWh on standard plans.

That means every kWh you use yourself is worth roughly two to four times more than every kWh you export. Self-consumption is the engine of solar economics in New Zealand. Buy-back is the icing.

The Numbers That Actually Matter

Let us put some real ranges on the table. The figures below reflect the public-facing solar plans of major NZ retailers as of 2024-2025. We maintain a live comparison view inside the Dynamic Tariff and Buy-Back Engine because these numbers do shift, sometimes quarterly.

• Basic flat buy-back (Genesis, Mercury, Contact standard solar plans): approximately 7 to 12 cents per kWh exported, paid 24/7 at a flat rate.
• Premium flat buy-back (Ecotricity standard solar): often higher than the big-three average, in the 12 to 17 cent range on plans designed for solar households.
• Peak-export plans (Ecotricity Resi-Flex): a flat rate the rest of the time, but a significantly elevated rate (well above 17 cents) during defined peak network hours, typically weekday evenings.
• Time-of-use solar plans (Meridian, some Contact variants): different rates for peak, shoulder and off-peak periods, with peak export sometimes paying more than peak import.
• Fully dynamic plans (Octopus Energy NZ): wholesale-linked pricing that changes every 30 minutes, with both import and export prices tied to the spot market.

The Electricity Authority publishes its Retail Quarterly Report and maintains Powerswitch as a comparison tool. We strongly recommend using Powerswitch as your second opinion alongside our own tariff engine; the two together give you a sanity check before you sign.

A worked example: 5 kW system in Hamilton

Consider a 5 kW system on a typical Hamilton home generating around 6,500 kWh a year, with a household that consumes 8,000 kWh a year. With sensible scheduling (laundry on sunny afternoons, hot water cylinder on a solar diverter), the family self-consumes about 45 percent of what the panels produce.

That means roughly 2,925 kWh stays in the home (avoiding a 30 cent import) and 3,575 kWh is exported (earning the buy-back rate).

• On a 8c flat buy-back: export earnings of about $286 per year, plus import savings of about $878. Total annual benefit: $1,164.
• On a 17c flat buy-back: export earnings of about $608 per year, plus the same import savings. Total annual benefit: $1,486.
• On a peak-export plan averaging 25c effective during exported peak windows: export earnings of about $890+, plus import savings. Total annual benefit: $1,750+.

The gap between the lowest-paying and best-fit plan, for this same household with the same hardware, is more than $500 a year. Over a 15-year horizon that is the cost of an entire battery. Tariff choice is not a footnote; it is part of the system design.

Flat Rates Versus Dynamic Rates: The Real Difference

Most NZ solar buy-back plans fall into one of two structural buckets. Understanding which one suits you is more important than chasing a particular cents-per-kWh figure.

Flat-rate buy-back

You get paid the same amount per exported kWh, every hour of every day. Simple, predictable, easy to forecast. Suits households that cannot or do not want to shift their consumption patterns: shift workers, families with very fixed routines, or anyone who just wants the bill to be simple.

The ROI Pragmatist persona often lands here. A flat rate makes payback modelling clean and a 12-year payback feels reassuringly predictable.

Time-of-use and peak-export plans

You get paid more during defined peak network hours (commonly weekday evenings 5pm to 9pm) and less, or sometimes nothing extra, the rest of the time. The trick is that on a sunny summer's day your panels are pumping power at midday when nobody else needs it; the peak window is 5pm when production is tailing off.

These plans suit households with a battery. A battery soaks up midday solar and discharges into the grid during the peak window when each exported kWh is worth two or three times more. Without a battery, peak-export plans can still work for some homes, especially in winter when generation is more spread out, but the upside is much smaller.

Dynamic, wholesale-linked plans

Plans like Octopus Energy NZ's offerings pass the wholesale spot price through to you, recalculated every 30 minutes. When the national grid is stressed (cold winter evenings, scarce hydro), export prices can spike dramatically. When the country is awash with solar and wind, prices drop, occasionally even to zero or negative.

This is the playground of the Tech-Savvy Optimiser. Combined with a battery, smart EV charger and a willingness to glance at an app, these plans can produce returns that flat plans simply cannot match. They also carry more variability, which means they are not for everyone. The Octopus Energy tariffs guide goes deep on the specifics.

The Importance of Timing Your Energy Use

Once you have your tariff sorted, the next lever is behavioural. Even small shifts in when you use power can move your annual benefit by hundreds of dollars.

The principle is simple. On a flat-rate plan, push as much consumption as possible into daylight hours (high self-consumption) so you are avoiding the 30c+ import rate. On a time-of-use or dynamic plan, shift heavy loads (dishwasher, washing machine, EV charging) to whichever period gives the best value: low-cost off-peak imports overnight, or high-paying export windows in the evening if you have a battery.

The easiest wins for most NZ households:

• Hot water cylinder: switch from controlled night-rate to a daytime element timer, or install a solar diverter. Hot water is typically 30 to 40 percent of a household's electricity demand.
• Dishwasher and washing machine: use delay-start to run between 11am and 3pm on sunny days.
• EV charging: schedule to charge during the most affordable import window for your plan. On dynamic plans this can be near-free; on flat plans it is usually overnight.
• Heat pump: pre-heat or pre-cool the house mid-afternoon so the work is done before the peak window.

None of this requires a battery. Behavioural shifting alone often adds 5 to 15 percent to a solar system's annual return. A battery layered on top is then about capturing the rest.

Topic Map: The Articles in This Silo

This pillar is intentionally a wide-angle view. Each of the articles below takes one piece of the puzzle and goes properly deep. Use them as you need them.

Octopus Energy Tariffs Explained: OctopusPeaker vs OctopusFlexi

Octopus Energy NZ has imported the dynamic-tariff model that worked so well in the UK and adapted it for the New Zealand market. This cluster article walks through OctopusPeaker (the peak-export plan) and OctopusFlexi (the wholesale-linked plan), with worked examples showing when each one pays off. Essential reading for anyone with, or considering, a battery. Read the Octopus Energy guide.

How Ecotricity's Resi-Flex Peak Export Plan Works

Ecotricity is one of NZ's certified carbonzero retailers and their Resi-Flex plan is built specifically around rewarding solar households for exporting during peak network demand. This cluster article unpacks the rate structure, the eligibility rules, and who actually benefits. Read the Ecotricity Resi-Flex guide.

Meridian Energy Solar Buy-Back Plans Explained

Meridian is one of the big-five gentailers and its solar plans tend to fly under the radar despite being competitive for the right kind of household. This article looks at the headline buy-back rate, how it stacks up against Genesis, Contact and Mercury on the import side, and which household profiles get the best result. Read the Meridian guide.

More cluster articles in this silo are in the pipeline, including deep dives on the controlled-rate hot water trap, the lines-charge differences between Vector, Orion and Wellington Electricity, and a head-to-head between the four most popular solar plans for households without batteries. They will be linked here as they are published.

What This Means for the Three Buyer Types

One of the reasons solar advice gets messy is that retailers and installers tend to recommend the same plan to everyone. Different households need different things. Here is how we think about it.

For the ROI Pragmatist

Your priority is a clean, defensible payback calculation. You want to know what you will earn each year and you want minimal admin. We typically suggest:

• Start with a flat-rate solar plan from a competitive retailer (Ecotricity, Mercury or a similar specialist plan).
• Use the Solar System Cost and ROI Calculator to model two scenarios: your current plan, and the best-fit solar plan.
• Avoid dynamic plans unless you genuinely enjoy optimising. The cognitive load is real and the marginal gain may not be worth your time.

For the Tech-Savvy Optimiser

You want to extract every cent. A dynamic plan paired with a battery and a smart EV charger is your natural fit. Look at:

• Octopus Energy NZ's dynamic offerings, modelled honestly against your actual half-hourly consumption data (request it from your current retailer).
• Peak-export plans like Ecotricity Resi-Flex if you want some of the upside without the half-hourly volatility.
• Hardware that can be scheduled programmatically: hot water diverters, smart EV chargers, and batteries with open APIs.

For the Eco-Conscious Family

You want the panels to do the most good, both for your household and for the wider grid. The good news is that exporting during peak network hours is also when the grid is dirtiest (firing thermal peakers at Huntly or Whirinaki), so maximising peak export is the most carbon-displacing thing your panels can do. Consider:

• Ecotricity or Meridian for their renewable-energy positioning and solar-friendly plans.
• A modestly sized battery (5 to 10 kWh, LiFePO4 chemistry) to shift export into the peak window.
• Locking in long, stable plans rather than chasing the absolute highest number; consistency matters for your peace of mind.

The Common Traps NZ Homeowners Fall Into

This is where we earn our keep. The Trust Proxy job. The following are the genuine, repeatable mistakes we see homeowners make, and they are the mistakes the installer almost never warns you about because the installer's commission is on the panels, not the plan.

Trap 1: Chasing the headline buy-back rate

A retailer advertising 17 cents per kWh export looks fantastic until you read the import side and discover their daily fixed charge is 60 cents higher than the competitor's and their peak import rate is 5 cents per kWh more. Always model the whole bill, not just the export line.

Trap 2: Signing the installer's recommended retailer without shopping around

Some installers have referral relationships with specific retailers. The plan they suggest may be a fine plan, but it may also not be the best plan for your household. Always cross-check on Powerswitch and our own tariff engine before you sign.

Trap 3: Staying on a controlled night-rate hot water plan after installing solar

This is the single most common configuration mistake we encounter. Pre-solar, controlled night-rate hot water was a money-saver. Post-solar, it actively destroys your economics: the cylinder fires at 11pm using imported power instead of soaking up free solar at 1pm. Get a sparkie in to move the cylinder onto the uncontrolled (anytime) circuit and put it on a timer.

Trap 4: Assuming export rates will stay where they are forever

Buy-back rates change. They have generally trended upward over the past five years as retailers have competed harder for solar customers, but there is no guarantee. Treat the export number in your ROI calculation as a reasonable estimate, not a contractual promise, and pad your payback calculation by a year or two for safety.

Trap 5: Over-investing in a battery just to chase peak-export arbitrage

Batteries are wonderful pieces of kit but they have a payback period of their own. A battery purchased solely to earn an extra few cents on peak export will often not pay itself off before its warranty expires. Buy a battery for resilience, self-consumption, and EV-charging flexibility; peak-export arbitrage is a bonus, not the business case.

Trap 6: Locking into a long fixed-term solar plan without an exit clause

Read the contract. Some specialist solar plans come with 24-month terms and break fees. The market is moving fast and you want flexibility to switch when something better appears. Month-to-month or 12-month terms with low exit costs are the safest choice for most households.

How to Use This Resource

If you are at the very start of your solar journey, start with the parent pillar, Your Guide to NZ Solar Tariffs and Retailers. It frames the whole landscape.

If you are partway through and need to compare specific plans, jump straight to the Dynamic Tariff and Buy-Back Engine. It is a free tool, kept current, and it does the heavy lifting of comparing dozens of plans for your actual usage profile.

If you have a system and you just want to know whether you are on the right plan today, run the engine first, then read the cluster article for whichever retailer it suggests. If you are still in the financing stage, the Green Finance Qualifier Tool will help you work out whether you qualify for the 0 to 1 percent green loans the big four banks now offer for solar.

And whatever you do, do not sign a quote without modelling the tariff side. The hardware decision and the retailer decision are two halves of the same investment.

Frequently Asked Questions

What is the average solar buy-back rate in NZ in 2024-2025?

The market range is roughly 7 to 17 cents per kWh on standard flat plans, with peak-window prices on dynamic and time-of-use plans occasionally going much higher. The simple average across the major retailers sits around 11 to 12 cents per kWh, though that figure hides large differences in plan structure.

Is the buy-back rate regulated by the government?

No. New Zealand does not have a nationally mandated minimum buy-back rate. The Electricity Authority sets market rules but each retailer sets its own buy-back rate as a commercial decision. This is why shopping around matters so much.

Why is my buy-back rate lower than my import rate?

Because the import rate includes lines charges, network charges, retailer margin and GST, while the export rate is essentially a wholesale-style price paid back to you. The structural gap means self-consumption (using your own solar in your own home) is always worth more than exporting it.

Will adding a battery improve my buy-back returns?

A battery improves overall solar economics by raising your self-consumption rate and, on time-of-use or dynamic plans, by allowing you to time-shift export into the highest-paying windows. Whether the battery pays for itself depends heavily on your tariff plan and household profile; the ROI calculator can model this for you.

Can I switch retailers after my solar is installed?

Yes, easily. Switching takes a few business days and there is no impact on your hardware, your panels, or your installer warranty. The main constraint is any fixed-term contract with your current retailer; check for break fees before you switch.

Do I need a special meter for solar export?

Yes, your home needs an import-export (smart) meter, sometimes called a bi-directional meter. The vast majority of NZ homes now have these as standard, but if you have an older mechanical meter your retailer will arrange a swap, usually at no cost, as part of your solar connection.

What is a dynamic tariff and is it worth it?

A dynamic tariff is one where the price you pay or receive changes throughout the day, often every 30 minutes, in line with the wholesale electricity market. It can be very profitable for households with batteries and flexible loads (like an EV) but it requires more engagement than a flat plan. The Octopus Energy guide covers this in detail.

How long does a buy-back rate stay the same?

Most retailers can change their rates with 30 days notice, in line with general electricity market practice. In practice, rates tend to be stable for six to twelve months at a time but you should not assume today's number will be unchanged in five years.

Does my lines company affect my buy-back rate?

Indirectly, yes. The lines charge a retailer pays to your local distributor (Vector in Auckland, Orion in Christchurch, Wellington Electricity in the capital, and so on) feeds into the import side of your bill, and some retailers structure their solar plans around specific network areas. Buy-back rates themselves are set by the retailer, not the lines company.

What is a peak-export plan and who should consider one?

A peak-export plan pays a much higher rate for power exported during peak network hours (typically weekday evenings) and a standard rate the rest of the time. They are best suited to households with batteries that can store midday solar and discharge it during the peak window. The Ecotricity Resi-Flex guide walks through one of NZ's best-known examples.

Will exporting more solar make my power bill negative?

Possibly during summer months, but rarely on an annual basis for an average-sized system. You still pay daily fixed charges to your retailer (usually 50 cents to $2.50 per day depending on plan and region), and most homes consume more in winter than they generate. A bill credit balance that runs down over winter is the norm.

What happens if I install a bigger system than my retailer's export limit?

Most NZ lines companies cap residential solar exports at 5 kW per phase without a special application. If your system is larger you can either curtail export (the inverter throttles back), apply for a higher export limit, or use a battery and load-shifting to consume more onsite. Always confirm export limits with your lines company before sizing your system.

Should I sign with the retailer my installer recommends?

Maybe. The installer's recommendation may be a perfectly good plan, but it may also reflect a referral relationship rather than the best fit for your household. Cross-check on Powerswitch and on our tariff engine before signing.

Where to Go From Here

If you read only four more things in this silo, make them these. Start with the Dynamic Tariff and Buy-Back Engine to see your actual numbers. Then read the retailer cluster that matches your shortlist: the Octopus Energy guide, the Ecotricity Resi-Flex guide, or the Meridian Energy guide. Finally, if financing is on your mind, run the Green Finance Qualifier while you are still in the planning stage; it is much easier to do upfront than to refinance later.

And if you have not yet got installer quotes, that is the obvious next step. Quotes that include the right hardware for your tariff strategy are worth dramatically more than quotes that just propose generic panels and walk away.