NEOBIOME

URL_024: EECA (2026) — TIMES-NZ 3.0 model documentation (ReadTheDocs)

Properties5
typesource
source_typeurl
authorEnergy Efficiency and Conservation Authority (EECA), BusinessNZ Energy Council, Paul Scherrer Institut
year2026
topicsmethodology_frameworks, energy_generation, regulation_policy, nz_specific

14 min read

URL_024: EECA (2026) — TIMES-NZ 3.0 model documentation (ReadTheDocs)

Source

https://times-nz-dev.readthedocs.io/en/latest/index.html — original source (opens in a new tab; the file is not redistributed)

EECA (2026) — TIMES-NZ 3.0 model documentation (ReadTheDocs)

The substantive assumptions-and-methodology documentation for TIMES-NZ 3.0, New Zealand's flagship national energy-system model, maintained by EECA. This is the real ingest target behind the URL_005 pointer — the paradigm FOIL for the thesis: a whole-of-NZ, least-cost linear-programming optimisation (base year 2023, milestone projections to 2030/2050, model period to 2060) resolved to two islands (North/South) and 24 timeslices/year, driven by two scenarios (Steady, Shift) along four critical uncertainties. It has no community/spatial resolution — precisely the gap the community-scale Neobiome Intelligence layer occupies.

Read verbatim via pdftotext → data_quality: verified. ⚠ It is a web capture of a living docs site (no official PDF build exists; figures are as-at 2026-07-16) and developer self-documentation of a model — quantitative values are model input assumptions (often ranges, rebased to 2023 NZD), not measured outturns. context: thesis, feeds: []: TIMES-NZ is the national-optimisation foil, not an NI input.

Summary

This is the ReadTheDocs documentation site for TIMES-NZ 3.0, the third iteration of New Zealand’s national-scale energy-system optimisation model, maintained by the Energy Efficiency and Conservation Authority (EECA) and co-developed with the BusinessNZ Energy Council (BEC) and Paul Scherrer Institut (PSI) on the IEA-ETSAP TIMES framework. The site “references all data, assumptions, and methods used to build the TIMES-NZ model” and is organised into Assumptions (demand sectors: Agriculture/Forestry/Fishing, Commercial, Industry, Residential, Transport; supply & transformation: Electricity generation, Oil & gas supply, Biofuel supply, Hydrogen; plus model-wide constraints), Scenarios (narratives + parameters), a Developer guide, and a Changelog (current release 3.0.7). The model produces a least-cost solution — a linear program that meets projected energy service demand at minimum system cost — over a horizon calibrated to a 2023 base year with milestone projections to 2030 and 2050 and equipment lifetimes running to a 2060 model period. It resolves NZ to a two-region structure (North Island / South Island, linked by a separately-modelled HVDC) and each year to 24 timeslices (4 seasons × 2 day types × 3 times of day; peak = the 6–7 pm hour). Two mutually-exclusive scenarios, Steady and Shift, are defined along four critical uncertainties (economic structure, technology costs, individualistic vs cooperative policy/behaviour, and the role of natural gas), and are parameterised with distinct carbon prices, discount rates, gas/LNG availability, and technology-cost decline paths. TIMES-NZ 3.0 is open-source: a Python data-preparation pipeline (PREPARE-TIMES-NZ) feeds Excel tables read by VEDA/XL2TIMES into GAMS for solving, with results published in a public Explorer app (via the TIMES-NZ-INTERNAL-QA module) “at the highest possible level of detail to ensure transparency.” For the Neobiome project its value is as the dominant NZ national-modelling paradigm — the top-down, national-aggregate, least-cost foil against which the bottom-up, community-scale, deployment-design Neobiome Intelligence layer is positioned; it also supplies a set of authoritative NZ-specific national assumptions (carbon prices, discount rates, hydrogen electrolyser CAPEX, HVDC and transmission/distribution costs) useful as macro cross-checks.

Key claims

- claim: "TIMES-NZ is 'a national energy system model for New Zealand, built using the TIMES modelling framework', maintained by the Energy Efficiency and Conservation Authority (EECA). The documentation site 'references all data, assumptions, and methods used to build the TIMES-NZ model.' The model 'produces a model solution that meets projected energy demand while minimising costs' — i.e. a least-cost optimisation. Demand is modelled as energy SERVICE demand (the useful service, e.g. km travelled or space heating), not fuel demand: 'the model would not use projections of natural gas demand. It would instead use projections of space heating demand, then find the least-cost way of meeting this using available technologies and input fuels.'"
  source_location: "TIMES-NZ documentation index (index.html); Electricity generation → Overview §1 (electricity/overview.html); Scenarios → Parameters, Economic Structure (scenarios/parameters.html)"
- claim: "TIMES-NZ solves as a linear program by default: 'In its default state, TIMES reaches an optimal model solution as a linear programming solution. This means that it could choose to build, for example, a fraction of an LNG import terminal. This is not realistic, so we limit LNG import options to \"integer states\"... This requires a Mixed Integer Programming solution, which increases the computational load of the model but is necessary for plausible results.'"
  source_location: "Oil and gas supply → Imported LNG, footnote [5] (oil_gas/imported_lng.html)"
- claim: "Temporal structure: TIMES-NZ 3.0 was 'Rebuilt and updated model for base year 2023 and new Steady and Shift scenarios.' Projections are anchored to the base year: 'The base year of 2023 was estimated using the EEUD, with 2030 and 2050 projections being made based upon assumptions of the TIMES-NZ team.' Long-lived equipment lifetimes run 'out to 2060 (i.e. the full TIMES model period).'"
  source_location: "Changelog 3.0.0 (changelog.html); Commercial → Technology parameters §4.6 (commercial/technology_parameters.html); Industry → Technology parameters §4.1.2 (industry/existing_techs.html)"
- claim: "Spatial resolution: 'TIMES-NZ operates on a 2-region model (North and South Islands), and the HVDC link is represented separately.' There is no sub-island, regional, or community spatial disaggregation in the solved model — regional demand data (e.g. residential by region and dwelling type) is aggregated up to per-island demand for use in the model itself."
  source_location: "Electricity generation → Transmission and distribution §4 (electricity/transmission_distribution.html); Residential → Demand projections (residential/demand_projections.html)"
- claim: "Temporal-within-year resolution: 'TIMES-NZ models electricity demand in \"timeslices\" each year. These split the year into 4 seasons, 2 day types (weekends and weekdays), and three times of day (day, night, and peak), for a total of 24 different times of year. We define peak as the hour from 6-7pm.'"
  source_location: "Residential → Demand curves §6 (residential/residential_demand_curves.html)"
- claim: "Scenario framework: 'The TIMES-NZ scenario narratives reflect four critical qualitative uncertainties' — Economic structure (traditional vs structural shift), Technology costs (trade/synchronicity with the world), Individualistic or cooperative (policy settings and consumer behaviour), and the role of Natural gas. 'We define two distinct narratives along these critical uncertainties: Steady and Shift. These represent mutually exclusive combinations: all critical uncertainties differ between the two scenarios.' Each scenario is 'intended to represent a plausible and realistic future pathway.'"
  source_location: "Scenarios → Narratives and Definitions (scenarios/narratives.html)"
- claim: "Carbon price by scenario: in Steady 'the carbon price stabilises at $52/tonne by 2035, in line with government carbon price projections'; in Shift 'carbon prices rise to $260/tonne by 2050, in line with the Climate Change Commission's demonstration path.' (Table 115 National outlook parameters: Steady 'Reaches $52/tonne by 2035 then stabilises'; Shift 'Reaches $260/tonne by 2050, matching the Climate Change Commission's updated demonstration path.')"
  source_location: "Scenarios → Narratives and Definitions + Parameters, Table 115 National outlook parameters (scenarios/parameters.html)"
- claim: "Discount rates by scenario (Table 115 + footnotes): Public sector — 8% (Steady) / 2% (Shift), taken from Treasury's public-sector discount rates and applied to schools and hospitals only. Businesses — 10% (Steady) / 8% default with 5% for green investments (Shift); the 10%/8% rates are representative of WACC, and the 5% rate is an assumed green-finance discount rate (Shift only). Households — 'As per businesses' in both scenarios (the model uses the same rate for households and businesses, acknowledged as contrary to evidence that consumers use higher discount rates, e.g. the US EIA's 20% for residential)."
  source_location: "Scenarios → Parameters, Table 115 National outlook parameters + footnotes [6][7][8] (scenarios/parameters.html)"
- claim: "Natural gas / LNG parameters (Table 116): domestic natural gas wholesale price 'Rises to $35/GJ as indigenous supply declines' (same in both scenarios); a 'Standard LNG terminal available in 2027 if selected by the model as the least-cost option' in Steady, while 'LNG not available in Shift scenario.' Domestic production follows the latest MBIE 2P production profiles 'with Maui assumed to close at the end of 2026.'"
  source_location: "Scenarios → Narratives and Definitions + Parameters, Table 116 Gas supply parameters (scenarios/parameters.html)"
- claim: "Hydrogen supply is produced only via electrolysis; electrolyser CAPEX assumptions (Table 116): Steady follows the CSIRO/Aurecon Current Policies pathway with 2035 electrolyser CAPEX of about NZD 2,120-2,225/kW and 2050 CAPEX of NZD 1,732-1,824/kW; Shift follows the CSIRO Post 2050 net zero pathway with lower 2035 CAPEX of about NZD 1,331-1,396/kW and 2050 CAPEX of NZD 1,127-1,183/kW."
  source_location: "Scenarios → Parameters, Table 116 Gas supply parameters, Hydrogen supply row (scenarios/parameters.html)"
- claim: "HVDC (Cook Strait inter-island link) assumptions (Table 79): Efficiency 97%; Investment cost $650m NZD/GW; Fixed OM costs $80m NZD/GW/year; current Capacity 1,200 MW (limited to 950 MW southbound), rising to 1,400 MW from 2031 (limited to 950 MW southbound) following Transpower announcements. Losses can reach 10% at peak demand but TIMES-NZ uses a simple average 97% efficiency; HVDC cost and timing assumptions are fixed (do not influence the model's investment/dispatch decisions)."
  source_location: "Electricity generation → Transmission and distribution §4.3, Table 79 HVDC assumptions (electricity/transmission_distribution.html)"
- claim: "Transmission & distribution network assumptions (Table 78, 2023 NZD): Investment cost ($m/GW) — Transmission 700, Distribution 2,371.10; Fixed OM ($m/GW/year) — Transmission 108, Distribution 296.2; Efficiency — Transmission 98.50%, Distribution 94.60%; existing capacity (GW) — Transmission NI 5 / SI 2.5, Distribution NI 4.74 / SI 2.07. Distribution capacity is anchored to Maximum Coincident System Demand (MCSD), which 'was 6.81GW in 2023.'"
  source_location: "Electricity generation → Transmission and distribution §4, Table 78 + §4.2 Distribution (electricity/transmission_distribution.html)"
- claim: "Open-source / reproducibility / outputs: the project 'Hosts all data and assumptions used for TIMES-NZ, untouched from source files', processes them, 'Outputs clean, machine-readable data for each key component', and formats them 'into the excel tables intended to be read by Veda or XL2TIMES before sending to GAMS for solving.' Per Changelog 3.0.0, the initial build of the PREPARE-TIMES-NZ module had 'All preprocessing methods migrated to python and open-sourced, to ensure replicability and tracability', and the TIMES-NZ-INTERNAL-QA module hosts results publicly: 'Results hosted publicly and can be explored at the highest possible level of detail to ensure transparency.'"
  source_location: "Developer guide → overview (developer_guide/index.html); Changelog 3.0.0 (changelog.html)"
- claim: "Model-wide currency/FX assumption: 'We hold exchange rates constant at 0.60 USD per NZD, as per other modules of TIMES-NZ.' Cost values across the model 'are adjusted to 2023 New Zealand dollars using the most appropriate price index (CPI or CGPI).'"
  source_location: "Oil and gas supply → Imported oil products §4 (oil_gas/imported_oil_products.html); Commercial → Technology parameters (commercial/technology_parameters.html)"

Key thesis insights

TIMES-NZ 3.0 is the paradigm the thesis argues alongside and past, not a data input. Its documentation lets the thesis characterise the dominant NZ energy-modelling approach precisely and name the resolution gap that a community-scale layer fills.

  • It is national-aggregate, least-cost linear optimisation with no community resolution. The solved model is a linear program (MIP only where discrete builds like an LNG terminal require it) minimising whole-of-system cost to meet projected energy service demand, resolved to just two regions (North/South Island) and 24 timeslices/year. There is no sub-island, settlement, or community-scale spatial detail — regional/dwelling-type demand data is aggregated up to per-island totals before solving. This is the concrete methodological contrast the thesis draws: TIMES-NZ optimises the national system; Neobiome Intelligence designs and assesses a single remote community’s deployment. Different objective (national least cost vs community self-sufficiency), different decision-maker (system planner vs community), different unit (island vs site).
  • Its scenarios are qualitative-narrative-driven, not a forecast. TIMES-NZ 3.0 runs two mutually-exclusive scenarios, Steady and Shift, defined along four critical uncertainties (economic structure, technology costs, cooperative-vs-individualistic policy/behaviour, natural gas) — each “a plausible and realistic future pathway”, not a prediction. This reinforces the epistemic frame already captured from URL_005 (the model “structures conversations about trade-offs”, not answers): even NZ’s flagship national model is a scenario/decision-support tool, a humility frame NI can adopt at community scale.
  • It encodes an explicit NZ national policy/price envelope. The scenario parameters pin authoritative national assumptions the thesis can cite as the macro backdrop: carbon price 52/t by 2035 (Steady) → 260/t by 2050 (Shift); public-sector discount rate 8% (Steady) / 2% (Shift) and business/household 10% / 8%+5%-green; domestic gas wholesale rising to $35/GJ, Maui closing end-2026, LNG in Steady only; hydrogen only via electrolysis with electrolyser CAPEX falling from ~NZD 2,120–2,225/kW (2035, Steady) to ~NZD 1,127–1,183/kW (2050, Shift). These are national input assumptions (often ranges from cited third-party pathways, rebased to 2023 NZD), useful as a sanity envelope but NOT community-scale inputs.
  • It is fully open-source and reproducible — inspectable by design. The PREPARE-TIMES-NZ Python pipeline, Excel model files (VEDA/XL2TIMES → GAMS), and a public results Explorer make the national model’s structure, assumptions, and outputs auditable. Implication for the thesis and NI: where boundaries overlap (e.g. national carbon/technology-cost trajectories), NI numbers can be cross-referenced against an open national least-cost baseline rather than a black box.
  • It anchors NZ-specific structural facts the thesis can reuse verbatim. Two-island + Cook Strait HVDC (1,200 → 1,400 MW from 2031, 97% average efficiency); the national grid as transmission (98.5% efficient) + distribution (94.6% efficient) with 2023 MCSD of 6.81 GW; a 2023 base year built bottom-up from the EECA Energy End Use Database (EEUD). These are authoritative national reference points for framing the scale and structure of the system a self-sufficient community sits inside (and partly exits).

Scope caveat (routing). This is context: thesis, feeds: []. TIMES-NZ is the national-optimisation foil, not a source of community-scale cost cells — NI already holds richer, community-resolution NZ cost evidence. The national assumptions above are recorded as documented claims and could serve as macro cross-checks, but are deliberately not wired to any NI calculation cell (a national model input assumption is not a community deployment cost).

Research targets

Resolved

  • RT_134 (RESOLVED → this page): the substantive TIMES-NZ 3.0 ReadTheDocs narrative — assumptions, sector coverage, scenario design (Steady/Shift, four critical uncertainties, carbon/discount/gas/H2 parameters), model structure (2-region, 24 timeslices, 2023 base year → 2030/2050 → 2060 horizon, linear/MIP least-cost), and output structure (open-source PREPARE-TIMES-NZ + public Explorer) — is now held and read verbatim.

Documents to retrieve

  • RT_135 (REMAINS OPEN — annotate, do NOT close): the TIMES-NZ 3.0 published scenario OUTPUT results and any accompanying EECA/BEC reports (the actual national energy-pathway numbers under Steady/Shift). This page is the assumptions/methodology documentation, NOT the results — the documentation confirms results are “hosted publicly and can be explored” in the TIMES-NZ Explorer app and are “made available separately.” RT_135’s real retrieval target is the Explorer app / EECA-BEC output reports, which this ingest does not deliver.

Research gaps

  • (folded into RT_135, not minted) — TIMES-NZ Explorer results extraction: a structured capture of the public TIMES-NZ 3.0 Explorer outputs (electricity generation mix, emissions trajectories, fuel shares by scenario/year) would give the thesis the national least-cost trajectories to position against, complementing this assumptions layer. It overlaps RT_135 directly, so it is folded into RT_135 (annotated ADVANCED) rather than minted as a new RT.

Notes

Authoritative EECA model documentation (times-nz-dev.readthedocs.io/en/latest/), captured 2026-07-16 as a 205-page PDF rendering of 79 documentation pages — read in full via pdftotext -layout, data_quality: verified. Every cited figure is traceable to a named documentation page/table in the capture (section paths and TIMES-NZ table numbers are given in each source_location). Same treatment as the sibling web capture URL_023 (authoritative page captured verbatim → verified).

Multi-file source → stored in the url_024_times-nz-3-model-documentation/ subfolder (L26 multi-file rule). The PDF (url_024_times-nz-3-model-documentation.pdf, sha256 5a29a775…, pinned in frontmatter) is the source of record; url_024_times-nz-3-model-documentation-source-capture.html (sha256 846b2ae2…) is the provenance capture documenting the origin webpage. Both are renamed to the canonical {page_stem}/… form at write.

⚠ Two epistemic caveats. (1) This is a web capture of a living documentation site — the project publishes no official PDF/epub build, so the figures reflect the site as at 2026-07-16 (release 3.0.7) and may since have changed; the changelog shows frequent assumption updates (e.g. 3.0.7 updated gas supply to MBIE 2026 reserves). (2) It is developer self-documentation of a model: the quantitative values are model INPUT ASSUMPTIONS — frequently ranges, often sourced from cited third-party pathways (NREL, CSIRO/Aurecon, MBIE EDGS, Climate Change Commission, Transpower RCP4) and rebased to 2023 NZD — NOT independently measured outturns. Cite them as “TIMES-NZ 3.0 assumes …”, not as observed facts.

Relationship to existing TIMES-NZ pages. URL_005 is the GitHub README pointer (thesis, medium) that logged RT_134 as the real target; this page fulfils it. OT_055 is the earlier TIMES-NZ 2.0 energy-scenarios narrative (ni, verified) — a different model version; this is 3.0, which the documentation notes was rebuilt bottom-up (e.g. asset-based generation fleet) relative to 2.0. No content overlap that constitutes a duplicate.

Connections

Links to

Sources (3): OT_055 · URL_005 · URL_023

Graph View

Backlinks