NZ hot-water cylinder + heat-pump-water-heater installed cost
Advances RT_003 — the household figures (kept OPEN for the community shared-tank gap)
A multi-source synthesis of NZ hot-water installed cost: a resistance cylinder ≈
3,000** (180 L) / **4,800 (300 L), or a heat-pump hot-water system ≈7,000** (190–300 L; **COP 3.2–4.0**). The household figures are well-converged (installer quotes + EECA); the **community / bare-vessel shared-tank/L is NOT publicly priced in NZ — that half of RT_003 stays open. Two EECA/PCE PDFs filed as primaries.
Source verification (audit 2026-06-22) — VERIFIED (mostly)
Heat-pump hot water **~
7,000 installed = VERIFIED** (EECA states "around7,000”); COP 3–4 VERIFIED (EECA Market Insights 2025, filed). ⚠ The resistance-cylinder ~$3,000 figure is NOT in any retrieved EECA document — it rests on un-retrieved NZ installer quotes (still unverified).
Summary
Hot water is ~30% of a NZ household’s energy bill, so its capital cost is a meaningful model cell. A standard resistance hot-water cylinder installs for roughly NZD 3,000 (180 L mains-pressure, ≈ 16/L) rising to ~**4,800** at 300 L — high confidence from converging 2025–26 NZ installer quotes. A heat-pump hot-water system (the efficient electric option) installs for roughly NZD 7,000 (190–300 L; EECA’s central “buy + install” figure), with a real range of 6,000–9,000 and up to 13,000 if the cylinder must be relocated; the unit alone is ~4,000+. Planning **COP is 3.2–4.0** (EECA's ≥3.2 subsidy floor; Stiebel Eltron's EN16147 seasonal 3.36–3.38; the Reclaim CO₂ "~5" is a vendor-favourable upper bound). The **community / shared-tank** segment that the RT_003 target asked for is **not publicly priced** in NZ — it is build-to-spec (Cooke Industries, Rinnai commercial, Central Heating NZ) — so the community /L is low-confidence and needs a vendor quote. Warmer Kiwi Homes caps heating grants at $3,450 incl GST, but that is a space-heating scheme; its applicability to hot-water heat pumps is unverified, so no subsidy should be defaulted.
Key claims
- claim: "NZ household hot-water installed cost: a resistance cylinder ≈ NZD 3,000 (180 L mains-pressure, ~$16/L; ≈ NZD 4,800 at 300 L) — HIGH confidence (converging 2025–26 NZ installer quotes, Sullivan/Regency); a heat-pump hot-water system ≈ NZD 7,000 installed (190–300 L; EECA central 'buy + install'; real range $6,000–9,000, up to $13,000 if the cylinder is relocated; unit-only ≈ $4,000+) — MED-HIGH. Planning COP 3.2–4.0 (EECA ≥3.2 subsidy floor; Stiebel Eltron EN16147 seasonal 3.36–3.38; Reclaim CO₂ '~5' is a vendor figure, treat as upper bound). Heat-pump HW running cost ≈ 25–35% of resistance; hot water ≈ 30% of household energy."
source_location: "EECA Hot water heat pumps + Insights + Market Insights (May 2025); PCE comparison; NZ installers (Sullivan/Regency/PERL/ArchiPro); Stiebel Eltron EN16147"
- claim: "Community / bare-vessel hot-water storage has NO established NZ public pricing — that segment is build-to-spec (Cooke Industries, Rinnai commercial, Central Heating NZ), so the community $/L is LOW confidence and needs a vendor quote (the RT_003 community shared-tank target is NOT closed). The ~$16–17/L derived from household cylinders OVERSTATES bare-vessel cost. Subsidy: Warmer Kiwi Homes caps heating grants at NZD 3,450 incl GST, but that is a SPACE-heating scheme; applicability to hot-water heat pumps is unverified — do NOT net a subsidy by default."
source_location: "Cooke Industries / Rinnai commercial storage tanks (no public price); EECA Warmer Kiwi Homes"Neobiome Intelligence relevance
A sourced hot-water (DHW) cost cell. The model can now price hot-water heating discretely — a resistance cylinder ≈ 3,000** or a **heat-pump hot-water system ≈ 7,000 (COP 3.2–4.0) — rather than lumping all heat into one heat-pump. This is the input a separated space-vs-water heat slice needs (when the heat slice splits domestic hot water from space heating, this gives the DHW capex + its own COP). Hot water ≈ 30% of household energy, so it is material.
⚠ Two honest limits:
- The original RT_003 ask — a community shared-tank $/L to recalibrate LIT_006’s payback — is not met; no public NZ pricing exists for bare-vessel/community storage → residual gap, needs a vendor quote (RT_003 stays open).
- Do not default a Warmer Kiwi Homes subsidy — it is a space-heating scheme; hot-water heat-pump applicability is unverified.
Retrieval provenance
A multi-source synthesis; the EECA Market Insights (2025) and PCE comparison PDFs are filed as primaries. Household installed-cost figures are well-converged (installer quotes + EECA); the community/bare-vessel $/L is honestly not established. ⚠ Method note: the agent fell back to WebSearch/WebFetch (US-indexed), so NZ installer quotes are indicative, not an exhaustive survey. The AI synthesis is filed as a _derivation note.
Research targets
Research gaps
- Community / bare-vessel hot-water storage tank $/L (300–10,000 L) — obtain a vendor quote (Cooke Industries / Rinnai commercial / Central Heating NZ) to close the unresolved half of RT_003 (the community shared-tank figure for LIT_006 recalibration).
- Confirm whether Warmer Kiwi Homes funds hot-water (not just space) heat pumps before netting any subsidy in the model.
Connections
Referenced by
Sources (3): CR_047 · OT_162 · RD_028
EDT domains (1): D01: Renewable Energy & Storage Systems