Survey focus: how the generation actually works
Ākonga compare solar, wind and hydro on output, siting, cost and consequence, including who carries the local impact.
- Applied Survey move: Multi-criteria comparison of three real technologies
- Evidence it produces: A ranked comparison where the criteria are stated before the ranking
Lesson at a Glance | He Tirohanga Whakamua
Ngā Whāinga Ako | Learning Intentions
Students will know
- How solar photovoltaic, wind turbine, and hydroelectric generation each produce electricity — at the level needed to explain the conversion of energy (not the underlying physics).
- The key LCA trade-off for each system: what its highest-harm stage is, what materials are needed, and how long it generates before decommissioning.
- That NZ generates approximately 85% of its electricity from renewables — predominantly hydro — and what this does and does not mean for total energy sustainability.
- That renewable energy projects in Aotearoa frequently intersect with Māori land rights, Treaty obligations, and the kaitiakitanga question of whose consent is required.
Students will demonstrate
- By completing a structured comparison of three renewable systems across five criteria — including both LCA performance and kaitiakitanga obligation — and identifying which system performs best under each criterion.
- By mapping NZ's current electricity generation mix using provided data, and naming one significant gap or tension in the current system.
- By writing Design Journal Entry 13: a 3–4 sentence argument for why "renewable" does not automatically mean "just," and what energy justice would require in a specific NZ context.
Do Now | Tīmatanga Whakaaro (8 min)
Display on the board — 3 minutes individual, 5 minutes class discussion:
"New Zealand generates about 85% of its electricity from renewable sources. Does that mean NZ's energy system is sustainable? Why or why not?"
Most students will say yes. Push: "What about the electricity used to make petrol? What about steel production? What about NZ's carbon emissions from transport and farming?" The goal is to create productive confusion — 85% renewable electricity is real progress, but total energy (not just electricity) tells a different story. This sets up the lesson's core complexity: renewable ≠ sustainable ≠ just.
Teacher note: NZ's 2024 total energy mix (not just electricity) is roughly 35–40% renewable when transport fuel is included. Electricity is the success story; the rest is not. Students who follow news may know about EV uptake, which is the connection between the renewable electricity system and transport decarbonisation. That's a good thread to pull on if it emerges.
Three Renewable Systems | Ngā Pūnaha Hiko (15 min)
Each system converts a different natural flow into electricity. Each has a different environmental footprint, a different land relationship, and a different LCA profile. Introduce each with NZ-specific context.
☀️ Solar Photovoltaic (PV)
Mature technologyNZ: ~2% of generationSilicon solar cells convert light directly to electricity. No moving parts during operation. NZ has good solar resource in the North Island (similar to southern Spain) but poor uptake due to historically low electricity prices and lack of subsidy compared to European markets.
LCA hotspot: Manufacturing. Producing silicon wafers is energy-intensive. A panel takes 1–4 years of operation to "repay" its manufacturing energy (energy payback period). End-of-life is a growing concern: panels contain lead and cadmium and currently go to landfill in most countries.
Land footprint: Relatively small per unit output if rooftop-mounted. Utility-scale solar farms use large areas — typically 1–2 ha per MW. Can be co-located with sheep grazing (agri-solar).
Kaitiakitanga question: Who owns the roof or the land the panels sit on? Rooftop solar concentrates benefit on the owner; utility-scale solar concentrates benefit in a corporate. Neither question is answered by the LCA.
💨 Wind Turbines
Fastest-growing globallyNZ: ~9% of generationWind turbines convert kinetic energy from moving air into electricity. NZ has one of the best wind resources in the world — the Roaring Forties cross the South Island. Projects like Tararua, Mill Creek, and the proposed Kaiwera Downs (Southland) represent different scales and contexts.
LCA hotspot: Manufacturing the blades (fibreglass composite, difficult to recycle) and the tower (steel, significant embodied carbon). Operational phase has near-zero emissions. Blades currently go to landfill at end of life — an unresolved problem as early wind farms begin decommissioning.
Land footprint: Turbines themselves are small; wind farms need large areas of land with spacing between turbines. The land between turbines can still be farmed. Turbines produce significant visual impact.
Kaitiakitanga question: Several NZ wind projects have been contested by iwi — Te Ātiawa and others have raised concerns about projects on or near wāhi tapu and Māori-owned land. The energy transition is not happening on politically neutral land.
💧 Hydroelectric Generation
Oldest renewableNZ: ~54% of generationWater stored at height is released through turbines to generate electricity. NZ's hydro system — Manapōuri, Roxburgh, Clyde, Benmore and others — was built between the 1950s and 1990s and forms the backbone of the national grid. The Waikato River dams are the most contested in terms of iwi relationships.
LCA hotspot: Construction (concrete dams have enormous embodied carbon). Reservoirs also emit methane from submerged organic matter — particularly in tropical climates, less so in NZ's cold storage lakes. Very long operational life (50–100 years), which spreads embodied carbon over many decades.
Land footprint: Very large. NZ's major hydro lakes are artificial; the Clyde Dam alone flooded the Cromwell Gorge, destroying a significant stretch of the Clutha / Mata-Au river ecosystem and forcing the relocation of an historic town.
Kaitiakitanga question: Waikato-Tainui have two settlements with the Crown, and the difference matters. The Waikato Raupatu Claims Settlement Act 1995 settled the raupatu — the Crown's 1863 invasion and the confiscation of over 1.2 million acres — and carried the Crown's apology. It did not cover the river. That took a second settlement: the Waikato-Tainui Raupatu Claims (Waikato River) Settlement Act 2010, whose stated purpose is to restore and protect the health and wellbeing of the Waikato River, through co-governance built on te mana o te awa. The river is an ancestor, not a resource. Many existing NZ dams were built on Māori land without full consent, and the kaitiakitanga accounting for those systems has never been completed.
Sources: generation shares — MBIE, Energy in New Zealand 2025 (2024 calendar year). Settlement history — Waikato Raupatu Claims Settlement Act 1995 and Waikato-Tainui Raupatu Claims (Waikato River) Settlement Act 2010, both readable in full on legislation.govt.nz. The Acts do not change; the generation percentages do, so check MBIE's current edition.
Key insight: All three systems have near-zero operational emissions compared to fossil fuels. The LCA differences are in manufacturing, land, and end-of-life — the same stages that kaitiakitanga asks about from a relational rather than a measurement perspective. The two frameworks complement each other here in a particularly direct way.
Video: Wind Energy and Iwi in Aotearoa (10 min)
Aotearoa New Zealand's First Emissions Reduction Plan — Ministry for the Environment (4 min 42 sec)
NZ has committed to reducing emissions. Why does the government see renewable energy as the primary tool? Write one prediction before you see the plan.
Identify two specific sectors the plan targets for emissions reduction. For each, note whether renewable energy is the solution proposed — or whether something else is needed.
The plan describes what NZ intends to do. Using kaitiakitanga as an additional lens: what does the plan leave out? Whose voices or relationships are not visible in this kind of policy document?
Teacher note: This video frames the emissions reduction plan from a government policy perspective — it is useful for establishing what NZ is officially committing to and why renewable electricity expansion is central. After viewing, bring in the kaitiakitanga lens: policy documents like this describe emission targets and technology pathways but rarely name the communities whose land those technologies will be built on. The question "who is consulted?" is the bridge from the policy video to the broader lesson. If the video is unavailable, use the NZ emissions reduction plan summary from the Ministry for the Environment's website as a reading instead.
Activity: Three-System Comparison | Whakataurite (15 min)
Score Each Energy System Across Five Criteria
Work in groups of three — one person takes primary responsibility for each system but all three discuss each criterion together. Score each system 1–3 for each criterion (3 = best performance). When you have scored all five, total the scores and compare the profiles.
| Criterion | Solar PV | Wind | Hydro |
|---|---|---|---|
| Operational emissions CO₂ per kWh during generation |
_ | _ | _ |
| End-of-life recyclability Can components be recovered and reused? |
_ | _ | _ |
| Land relationship Scale, permanence, and reversibility of land use |
_ | _ | _ |
| Community consent (NZ context) Ease of building with genuine iwi and community agreement |
_ | _ | _ |
| Intergenerational legacy What does this system leave future generations? |
_ | _ | _ |
Discussion questions: Does one system win on all criteria, or do different systems lead on different criteria? What does this tell you about how energy policy should be made — is there a single "best" choice? If you were advising the NZ government on its energy transition, which system would you prioritise expanding, and why?
NZ Energy Reality Check | He Arotake (8 min)
NZ Electricity Generation Mix (approximate, 2024):
Source: MBIE, Energy in New Zealand 2025 (2024 calendar-year figures). Total generation 43,879 GWh; renewables 85.5%, down from 88.1% in 2023 because a dry year cut hydro output to its lowest since 2013. Geothermal and wind both set records. These proportions move every year with rainfall — check MBIE's current edition before teaching them as fact.
These figures are electricity generation only — not total energy. NZ transport runs almost entirely on imported oil. Industrial heat uses significant gas. The 85% renewable headline is electricity; total primary energy is closer to 35–40% renewable when all uses are included.
Key tensions in the current system:
- Dry-year risk: When drought reduces lake levels, gas and coal generation increase. NZ's renewable lead is weather-dependent — a design vulnerability.
- Transpower grid: Much of NZ's renewable generation is in the South Island; most demand is in the North Island. The HVDC cable linking them is a single point of failure.
- Solar underinvestment: NZ has excellent solar resources but minimal deployment. The electricity market has not created incentives comparable to Europe or Australia.
📓 Design Journal — Entry 13: Renewable Is Not the Same as Just
Write 3–4 sentences responding to this prompt:
"Renewable energy reduces carbon emissions. But 'renewable' is not the same as 'just.' What would energy justice — using both LCA and kaitiakitanga frameworks — require in Aotearoa that the current renewable energy system does not yet provide?"
Your entry should name one specific gap in the current NZ energy system — not a general principle, but a concrete thing that is missing or unresolved. It should state whose interests are not yet fully served, and what one change would address that.
Exit Claim | Whakamutunga (4 min)
On a slip of paper (anonymous, collected at the door):
"The renewable energy system that best meets BOTH LCA and kaitiakitanga criteria in Aotearoa is ______, because ______."
Teacher use: There is no single correct answer here — the point is to see whether students are applying both frameworks simultaneously (LCA performance + land/consent/intergenerational relationship), not just one. Students who score solar highest on LCA but wind highest on land relationship have understood the frameworks correctly. Students who name hydro for intergenerational legacy (because dams last 100+ years) but acknowledge the unresolved kaitiakitanga debt are doing exactly the right kind of thinking.
Kaiako Planning | Ngā Tūāhu Whakaaro
📋 Curriculum Alignment
This lesson addresses the NZ Curriculum Technology strand: Technological Knowledge — Technological Systems. Students examine how energy generation systems function, what their inputs and outputs are, and how their design creates dependencies and trade-offs. The kaitiakitanga and energy justice dimensions connect to Technology and Society: understanding that technological systems exist within social, cultural, and environmental contexts that shape their impacts.
Science connections: Physical World (energy transfer and transformation). Social Sciences: Aotearoa New Zealand Histories (Māori land relationships and the energy transition). The energy justice framing is explicitly cross-curricular — it cannot be addressed from within a single discipline.
📦 Materials & Resources
- Students' Design Journal entries from Lessons 11 and 12 — useful reference for the comparison activity and journal entry
- Printed or projected version of the three-system comparison table (one per student or per group)
- Whiteboard for Do Now discussion
- Paper slips for exit claims
Data source for teacher: Electricity Authority of NZ (emi.ea.govt.nz) publishes live generation data. The approximate figures used in this lesson are 2024 averages — check annually, as NZ's solar and wind proportions are growing. Genesis Energy's Huntly power station (coal and gas) is the key variable in the "dry-year" scenario.
NZ-specific resource: The Parliamentary Commissioner for the Environment has published several accessible reports on NZ's energy transition and Māori interests. These are free to access and written at a level appropriate for teacher background reading.
🔄 Differentiation
For students who need more support: Pre-fill the operational emissions row of the comparison table (all three are very low — 1–3 g CO₂/kWh vs coal at 820 g CO₂/kWh) so students can see quickly that the LCA differences are elsewhere. Provide sentence starters for the journal entry. Reduce the reading load by having students work on only two of the three systems.
For students who move faster: Research the proposed Lake Onslow pumped-hydro scheme — a proposed large-scale energy storage solution that would use surplus renewable electricity to pump water uphill, then release it during dry years. What are its LCA implications? What are the kaitiakitanga questions? Why has it been controversial?
For students with engineering or physics interests: Two different percentages appear in this lesson and students conflate them constantly. Generation share is how much of NZ's electricity a source actually supplies (wind ≈ 9%). Capacity factor is how much of its own maximum a plant achieves on average (wind ≈ 35–40% at good sites; solar ≈ 15–20% in NZ; hydro ≈ 35–50% depending on rainfall). A source can have a high capacity factor and a small generation share, or the reverse — they answer completely different questions. Make the distinction explicit on the board before you use either number. Then ask students to calculate how much capacity you must build to generate a given amount of electricity annually — that calculation only works once the two ideas are separated.
For students interested in economics: The levelised cost of energy (LCOE) — the total cost divided by total electricity generated over the system's lifetime — is the standard economic comparison. NZ wind is currently among the cheapest electricity sources available. But LCOE does not include land rights, consent costs, or the unmonetised kaitiakitanga obligations. Ask students: what would happen to the LCOE if those were included?
⏭️ Next Lesson Connection
Lesson 14 (Sustainable Materials: Bioplastics and Upcycling) moves from energy systems to materials. Students will apply the same dual-lens — LCA + kaitiakitanga — to the question of what materials technology is made from and what happens to those materials after use. The energy lesson is relevant because many "sustainable" material alternatives (bioplastics, composites) are energy-intensive to produce — making the renewable energy question directly connected to materials sustainability.