Methodology

What goes in

Beacon uses public New Zealand electricity-market, transmission-network and geospatial datasets as source inputs to its screening model. These datasets are used as source inputs only. Lumere independently compiles, cleans, joins, calibrates, weights and interprets the data to produce Beacon's scores, classifications, rankings and commentary.

• 1. Transpower interconnection branch-capacity data. Beacon uses published Transpower interconnection branch-capacity files to identify indicative MVA ratings on transmission corridors. These files are published under the Electricity Industry Participation Code 2010 and are reusable under the Creative Commons Attribution 4.0 International Licence, with attribution to Transpower New Zealand Limited, as confirmed by Transpower in August 2026. Beacon uses this information as an indicative asset-capability input only. It does not represent confirmed transfer capacity, available capacity, operational grid capability, or project-specific connection capacity. Updated monthly where new files are published by Transpower.
• 2. Electricity Authority EMI nodal pricing and reserves. Beacon uses three years of half-hourly historical settlement prices at grid exit points to derive nodal price, spread, volatility and historical market-signal indicators, and three years of half-hourly reserve prices to derive island-level fast and sustained instantaneous reserve indicators. This information is used to identify historical market signals only. It does not forecast future prices, revenues, dispatch outcomes, or investment performance. Updated monthly.
• 3. Electricity Authority EMI generation and plant data. Beacon uses published metered generation output, embedded generation and dispatched generation plant data to identify existing generation at each connection point, and to measure what generating plant has historically earned relative to the average price. These measured indicators are Lumere-derived and are calculated only where sufficient metered history exists; where it does not, Beacon says so rather than substituting a national figure. This information describes historical performance only. It does not forecast future generation, capture, dispatch outcomes or revenue. Updated monthly.
• 4. Transpower Envision Opportunities information. Beacon uses publicly available Transpower Envision Opportunities information as a high-level input to its substation headroom screen. Beacon may derive or classify N-1 or headroom indicators from this information where available. These indicators are Lumere-derived screening outputs. They are not official Transpower outputs, not confirmed or available capacity, not Transpower advice, and not a substitute for a project-specific feasibility study or Transpower's connection process. Transpower New Zealand Limited has not reviewed, approved, endorsed or validated Beacon, Lumere's methodology, or any Beacon ranking, classification, score or recommendation. Any connection remains subject to Transpower's connection process and detailed technical assessment. Users should engage directly with Transpower and obtain appropriate technical, commercial and legal advice before making connection, development or investment decisions. Updated annually where new information is published by Transpower.
• 5. Transpower generation and battery connection pipeline. Beacon uses published Transpower generation and battery connection pipeline information, including announced and anonymised projects, project stage and MW where available. This information is used as a contextual and screening input to assess future connection activity, queue pressure, potential competition for capacity and development context. Connection pipeline data is reusable under the Creative Commons Attribution 4.0 International Licence, with attribution to Transpower New Zealand Limited, as confirmed by Transpower in August 2026. Beacon reproduces and adapts selected connection pipeline information as part of Lumere's independent methodology. The connection pipeline is indicative, subject to change without notice, and does not represent committed, approved, reserved or guaranteed connections. It does not indicate the availability of grid capacity at any location, and should not be relied on as evidence of the existence, progress, timing or likelihood of any connection or third-party project. Updated monthly where new files are published by Transpower.
• 6. Transpower load, storage and other non-generation connection pipeline. Beacon uses published Transpower load, storage and other non-generation connection pipeline information as contextual information on future demand, electrification, storage activity and local network pressure. Connection pipeline data is reusable under the Creative Commons Attribution 4.0 International Licence, with attribution to Transpower New Zealand Limited, as confirmed by Transpower in August 2026. Beacon reproduces and adapts selected connection pipeline information as part of Lumere's independent methodology. The connection pipeline is indicative, subject to change without notice, and does not represent committed, approved, reserved or guaranteed connections. It does not indicate the availability of grid capacity at any location, and should not be relied on as evidence of the existence, progress, timing or likelihood of any connection or third-party project. Updated monthly where new files are published by Transpower.
• 7. Transpower public GIS. Beacon uses Transpower public geospatial data for substations and transmission-line geometry, including mapping, spatial joins and corridor association. Transpower's open geospatial portal states that most of its public geospatial data is available under the Creative Commons Attribution 4.0 International Licence and must be attributed on maps, websites, applications or printed material using the data. Beacon uses Transpower public geospatial data with attribution to Transpower New Zealand Limited and in accordance with the licence or terms stated for the relevant geospatial dataset.
• 8. Stats NZ regional boundaries. Beacon uses Stats NZ regional boundary datasets for mapping, spatial analysis and regional grouping, including Regional Council 2025 boundaries where relevant. Stats NZ's Regional Council 2025 dataset is listed as Creative Commons Attribution 4.0 International and permits commercial use with attribution.
• 9. ASX New Zealand electricity futures. Beacon uses traded New Zealand electricity futures prices published by ASX to set the forward hub price for its 2028 view. A traded price reflects the market's view on the day it is read and changes as futures trade. Beacon applies its own locational and capture adjustments to it, so the result is a Lumere screening estimate. It is not a forecast and it is not an ASX output. Updated monthly.
• 10. Electricity distribution business network disclosures. Beacon uses network capacity information published by electricity distribution businesses as context for connections below the grid. From 1 December 2026, distribution businesses must publish capacity, congestion and queue information, and Beacon may draw on it as it becomes available. This information is indicative only. It is not confirmed capacity on any distribution network and is not a substitute for the relevant lines company's connection process.
• 11. Public project cost disclosures. Beacon's build cost rests on a bank of disclosed New Zealand project costs. A project enters the bank only under Lumere's written inclusion standard. The figure must come from the owner, the developer, a financier or government, or trade press quoting the owner. It must be the cost of one named New Zealand project at final investment decision or later, and never a capital raise or an early estimate. Solar capacity is taken on an AC basis, and where an owner states only DC capacity, AC is taken as DC divided by 1.25. The figure includes the connection works the project uses. The project must have reached commercial operation or final investment decision in 2023 or later, and be 20 MW or larger. The bank is blended with government and global benchmarks to form a low, middle and high build cost, regionalised by capacity factor. Lumere does not verify disclosed figures beyond their published source.

Beacon's 2028 view starts from the traded 2028 hub price on ASX New Zealand electricity futures. Beacon applies its own locational and capture adjustments, so the result is a Lumere screening estimate and not a forecast. A price-year toggle also shows the grade on today's prices.

Sources and licensing

Beacon is built from publicly available datasets published by New Zealand electricity-sector and government data providers. Lumere uses these datasets as source inputs only. Beacon's compilation, cleaning, joining, calibration, scoring, classification, ranking, commentary and commercial interpretation are Lumere's own work.

Where a source dataset is expressly licensed under the Creative Commons Attribution 4.0 International Licence, Lumere uses it under that licence and attributes the relevant source. Where Transpower has confirmed that a source dataset is reusable under the Creative Commons Attribution 4.0 International Licence, Lumere uses that dataset under that licence, attributes Transpower New Zealand Limited, identifies where Lumere has adapted or transformed the material, and does not imply endorsement by Transpower. Where a dataset is published without an expressly stated reuse licence, Lumere attributes the source and treats use as subject to any terms stated by the relevant publisher. Lumere welcomes contact from any data publisher regarding the use of its published material.

Source data and licence position

Independence and attribution statement

Beacon contains data sourced from Transpower New Zealand Limited, the Electricity Authority Te Mana Hiko, and Stats NZ Tatauranga Aotearoa. It also uses futures prices published by ASX, network disclosures published by electricity distribution businesses, and public statements of project costs and yields.

Lumere is independent of these organisations. Lumere is not endorsed by, sponsored by, affiliated with, authorised by, or acting on behalf of Transpower New Zealand Limited, the Electricity Authority Te Mana Hiko, Stats NZ Tatauranga Aotearoa, ASX, or any related agency.

Transpower New Zealand Limited has not reviewed, approved, endorsed or validated Beacon, Lumere's methodology, or any Beacon ranking, classification, score or recommendation.

Any Beacon analysis, compilation, transformation, calibration, scoring, ranking, classification, commentary or recommendation is Lumere's own work. It should not be attributed to, represented as approved by, or relied on as advice from any source data provider.

Source data is used on an "as published" basis. Beacon does not reproduce Transpower's tools, does not represent Transpower's operational view, does not represent confirmed connection capacity, and does not replace direct engagement with Transpower, the Electricity Authority, Stats NZ, network companies, generators, consultants or other relevant parties.

Beacon does not make Transpower's original source files available for download as source files. Where Beacon displays, reproduces or adapts selected Transpower connection pipeline information, it does so with attribution and subject to the important notice above.

Where applicable, source data is used under the Creative Commons Attribution 4.0 International Licence. CC BY 4.0 permits sharing and adaptation, including commercial use, provided appropriate credit is given, a link to the licence is provided, changes are indicated, and the use does not imply endorsement by the licensor.

Attribution

Beacon credits its openly licensed sources in the form each licensor specifies.

• 1. Transpower interconnection branch-capacity data. Source: Transpower New Zealand Limited. Published under the Electricity Industry Participation Code 2010 and reusable under the Creative Commons Attribution 4.0 International Licence, with attribution to Transpower New Zealand Limited, as confirmed by Transpower in August 2026. Used as indicative asset-capability information only.
  Licence: Creative Commons Attribution 4.0 International
• 2. Transpower connection pipeline data. Source: Transpower New Zealand Limited. Reusable under the Creative Commons Attribution 4.0 International Licence, with attribution to Transpower New Zealand Limited, as confirmed by Transpower in August 2026. Used as indicative contextual and screening information only.
  Licence: Creative Commons Attribution 4.0 International
• 3. Transpower Envision Opportunities information. Source: Transpower New Zealand Limited. Used with attribution as an indicative guide only. Beacon's derived headroom, N-1, scoring and classification outputs are Lumere-derived screening outputs and are not official Transpower outputs.
• 4. Transpower geospatial network data. Source: Transpower New Zealand Limited open geospatial data. Licensed under CC BY 4.0 where stated by Transpower for the relevant dataset, with attribution to Transpower New Zealand Limited.
  Licence: Creative Commons Attribution 4.0 International
• 5. Electricity market data. Source: Electricity Authority Te Mana Hiko / EMI. www.emi.ea.govt.nz provided by the Electricity Authority (New Zealand). Licensed under CC BY 4.0 unless otherwise indicated by EMI. Includes nodal pricing, reserves, metered generation output, embedded generation and the dispatched generation plant register. www.emi.ea.govt.nz
  Licence: Creative Commons Attribution 4.0 International
• 6. Regional boundaries. Source: Stats NZ Tatauranga Aotearoa. Regional Council 2025. Licensed under CC BY 4.0.
  Licence: Creative Commons Attribution 4.0 International

Licensing positions last reviewed: August 2026, following written confirmation from Transpower New Zealand Limited.

How we count the queue

Beacon counts every project in the connection queue at its full size, as if it builds. It does not discount a project for its stage or its consent.

Beside the full count, Beacon says how much of the queue is economic to build on today's costs. A reader sees what is queued and what is likely to pay, kept apart.

Beacon reads the Transpower generation and load connection queues each month. Where Transpower notes that existing generation sits inside a project's stated maximum, Beacon counts only the net new megawatts.

The grade

For solar and wind at each connection point, Beacon works out cover. Cover is what a farm would earn per megawatt hour divided by what it would cost to build per megawatt hour, the levelised cost of energy.

Earnings start from the traded 2028 hub price on ASX New Zealand electricity futures. Beacon multiplies that price by how the connection point prices against its hub and by capture, which is the share of the average price the technology earns in the hours it generates. A price-year toggle shows the grade on 2028 prices and on today's prices.

Build cost is the middle of Beacon's low, middle and high build cost estimates for the technology, regionalised by capacity factor. Beacon bands on the middle estimate and shows how the grade holds at the low and high ends.

Cover is measured against a 50 MW reference build. A build under 20 MW has its own letter.

Room to connect never changes the letter. It is shown beside the grade with the queue reading, so a well graded point that is full reads as both.

Beacon does not rate a technology at a point that is built up, lies in an outstanding natural landscape or protected area, or has too weak a resource for it, and the map says which. A battery has a band rather than a letter, set out below.

The grade never weights different kinds of measurement into one number, is never normalised against other nodes, and is never issued with a plus or a minus.

How to read the grade, and where it stops

The grade is a screening ratio, not a return. It compares a screening estimate of earnings with a middle screening estimate of build cost. It is not an internal rate of return, and a high grade is not a promise of a bankable project.

It reads the resource at screening level only. Capture and the regional capacity factor describe how the technology performs in the region, not the measured resource at your site. Weigh the site resource separately.

It does not price consenting, land, or the connection and network reinforcement cost specific to your site. A well graded point can still carry a large connection cost.

It uses a forward price that moves. The 2028 hub price is the traded futures price when the edition is built, and it changes as futures trade. It is a screening input, not a forecast.

The queue reading counts every queued project at its full size. As projects enter, resize or drop out, the queue reading changes the following month and the change is reported.

Room to connect is checked against the wires out wherever a published corridor figure exists. Where a bus has no route figure, it is still graded, because cover does not use a route, and its room to connect is shown as a bus figure that no export route confirms. Corridor coverage is expanding month on month.

Reading a node

A node is a grid connection point. At each node Beacon asks two separate questions. Would a solar or wind farm here earn enough to cover what it costs to build? Is there room on the grid to connect it? The first sets the grade, which is explained below. The second is shown beside the grade and never changes it.

For room to connect, Beacon compares the node's generation queue at full size against Beacon's headroom screen, a worst-case N-1 winter indicator derived by Lumere from publicly available Transpower Envision Opportunities information. This is a conservative screening indicator, not confirmed connection capacity, operational grid capability, or a substitute for project-specific feasibility studies.

Non-generation load is shown alongside as context and is not folded into the number, because its true effect on headroom cannot be settled without power-flow modelling and more detailed system analysis. A node-level read is also incomplete if the export corridors leaving it are already constrained, so the room to connect is the lesser of what the bus can carry and what the route out can carry.

• Room to connect. The lesser of the bus headroom screen and the route out. Where less than 50 MW is open, the figure is shown beside the letter.
• Queue. The Transpower generation queue at the node, counted at full size and as net new megawatts where existing generation sits inside a project's maximum.
• Full. Where the bus is full, or the visible queue takes the capacity on the forward view, the card says so beside the letter.
• Junction. Where circuits meet and nothing is metered, there is no connection to build and no grade is shown.

Reading a corridor

A corridor is a transmission route between nodes. The screening question shifts from connection headroom to export headroom. Does the published branch-rating data suggest this route has export capacity worth investigating further?

Corridor capacity is based on Transpower's published interconnection branch rating, the Summer Continuous MVA with one circuit out, converted to MW at a standard power factor. It is a transparent thermal screen, not a security-constrained transfer study and not confirmed available transfer capacity.

Beacon counts the queue the same way, at full size, then looks for the binding span. Where a corridor runs as parallel circuits, Beacon uses the most-loaded circuit as a conservative screening constraint for the route. On long multi-segment lines, such as Benmore to Islington, the most constrained segment along the chain sets the headline. Beacon flags that bottleneck branch so users can see which span appears to be the screening constraint.

• Room. 50 MW or more is free on the most constrained section once the full queue is counted.
• Tight. Less than 50 MW is free on the most constrained section.
• Full. No room is free on Beacon's screening method. Exporting more may require further technical assessment, changed assumptions, or network investment.
• Not read, or display only. Beacon holds no rating for the line, so it cannot say what gets out. Connection assets, tee-junctions and HVDC links appear for orientation only.

Bands and data quality

Each grade is set against fixed bars of cover. A is 1.30 or more, B is 1.15 or more, C is 1.00 or more, D is 0.85 or more, and E is below 0.85. The bars are never moved to produce a spread, so a grade does not change because another node changed, and two sites in the same band are in no order that means anything.

Every graded site also shows how its grade holds across the build cost range. It says whether the site still pays for itself if building costs come in high, only on the middle estimate, or only on a low build cost, and it shows the build costs at which its grade changes. You can compare your own build cost against those figures.

Where Beacon holds too few months of prices at a node, it publishes no grade there and says so. Where a reading rests on a modelled rather than a metered input, Beacon marks it provisional.

What is covered, and what is not

Beacon covers Transpower's published interconnection network, the high-voltage backbone with published capacity information. Nodes and branches with sufficient public inputs carry a grade or a room reading.

Beacon does not cover connection assets or radial feeds from the backbone to local grid exit points where equivalent public capacity information is not published in the same way. Those lines are drawn for orientation only, with no investment signal. HVDC links and infrastructure deviations are shown the same way. Where users see a point with no grade or a display-only line, it reflects missing, unpublished or unsuitable input data, not a representation that no operational issue exists.

Beacon does not rate a technology at a point that is built up, lies in an outstanding natural landscape or protected area, or has too weak a resource for it. These are screening exclusions only. They are not findings about whether a project could or could not be consented, built or connected there.

The battery read

Beacon gives a battery a band rather than a letter, because New Zealand battery build costs are still moving. The band describes the shape of the trading day at each connection point, read from historical EMI prices. It has three parts.

• The gap. Beacon measures how far the evening price sits above the cheapest block of the day at the node, averaged over five years. That gap is what a battery buys and sells across.
• On its own. Beacon compares what a battery trading that gap would earn with what it would need to earn to cover its cost. The need is set on a view of $560 per kWh of storage, which is a Lumere screening assumption and not a quote.
• Beside a farm. Beacon also reads a battery paired with a solar or wind farm, storing the farm's output when prices are low and selling it when they are high. Where a metered solar or wind farm operates within 100 km, its metered output is used. Where none does, the pairing is modelled on a typical generation shape and is marked provisional.

Every battery figure runs on prices that have already happened, and it treats the day's prices as known in advance, so read it as a best case rather than an expectation. It leaves out wear on the battery, network and connection charges, power used by the site itself, and money from contracts, reserves or network payments, any of which can change the case.

The band is a screening signal, not a bankability verdict. Beacon ranks no battery site by score and publishes no forecast for it.

What makes the daily price gap

A battery earns on the gap between the cheapest and dearest hours of the day. Beacon splits that gap in two. The evening climb is how far the dearest hours sit above the day's average, and it is the part that differs materially from one place to the next. The other part is the overnight dip, and it is close to the same everywhere, because the shape of the day is set across a whole island rather than at one node. The current spread of evening climb across the regions is on the monthly briefing, where it is restated each month against fresh prices.

Beacon also watches which part of the day is cheapest. Today it is overnight almost everywhere. If enough solar connects, the cheapest hours move to the middle of the day, and the best places for a battery move with them. Twelve of the forty eight half hours in a day sit in the midday window, so picking hours at random would put a quarter of them there. Days with almost no price movement are left out, because on those days the cheapest hours are close to random.

The middle of the day can also go cheap because the lakes are full or demand is low, so a rise in this number is a reason to look rather than proof that solar has changed the market.

How we measure change (What's Changed)

Each monthly edition compares this month with the month before. The prior month is restated on the same engines as this month, so a move reflects a change in the market or the queue and not a change in how Beacon measures it.

When Lumere changes a method, the change is told separately, with what moved because of it, and it is not counted as a market move.

A grade moves only when cover crosses one of the fixed bars. A node's grade never moves because a different node moved.

Regional editions use the same method inside the region and show the national picture alongside, so a quiet region is not mistaken for a quiet country.

Hydro years and the price cycle

New Zealand's wholesale price level is set substantially by hydro storage. A dry year can lift prices across an island for months at a time. A wet year can suppress them. The current three-year pricing window includes a clear dry period, and its imprint is most visible in South Island price levels. Any tool built on recent market data carries that cycle, so Beacon is explicit about where it shows up and how it is handled.

Absolute dollar figures, such as a node's three-year average price, are shown as they were earned. Beacon does not adjust them for hydrology because it holds no storage or inflow model, and a hydro-corrected price would be a modelled forecast, which Beacon deliberately does not publish. Instead, price bands are set against the national distribution, so a wet or dry year moves the whole distribution together rather than automatically flipping individual nodes between bands.

The grade is priced on the traded 2028 hub price, which carries the market's own view of hydrology for that year, so it does not lean on any single wet or dry year in the price record. How a node prices against its hub and what the technology captures are measured from the historical record and carry the cycle described here.

The node-specific signals are measured relative to the island. Price basis is the node against its island average. The battery spread edge is the node's spread against its island median. Solar and wind capture is read against the island reference. A hydro swing moves the whole island broadly together, so the island-relative read removes much of the common distortion. That is the deliberate design. Comparing a node to its island is Beacon's hydrology normalisation.

Trends are protected from single-month distortion. Twelve-month moves are measured between three-month medians at each end of the window, so one extreme hydro month cannot create a false trend, and a node whose year varied month to month is flagged rather than ranked.

Where a dry year widens price dispersion enough to weaken statistical confidence, the affected reads carry a lower confidence band, and material moves at those nodes are disclosed as suppressed rather than presented as clean signals.

The honest bound is that island-relative measures remove much, but not all, of the hydro effect. Dry years can also change the shape of the day and shift the balance between the islands across the HVDC link. That residual is part of why Beacon is a screening tool, and why every read should be tested against the user's own view of market conditions before capital is committed.

What Beacon is not