JB Solar & Electrical · internal working analysis
221 Molesworth Drive, Mangawhai Heads · 12 months of Community Power bills, Aug 2025 – Jun 2026 · site visit Thu 13 Aug, 11am
Read from 11 invoices covering 334 billed days. Every bill's usage cross-checks against the "total units used this bill" line on the invoice.
December to March runs 420–452 kWh/day. April to June drops to 322–340. That's a 35% summer lift, and it sits directly on top of the solar generation curve instead of fighting it.
Most jobs have the opposite problem — peak demand in winter, when the array produces least. Here the biggest bills land in the months of highest generation.
The Pumps ICP moves from about 1,500 kWh/month in winter to 3,900 in summer. The Club House stays flat at 7,300–9,000 kWh/month all year.
87% of pump usage is on the controlled (night) rate — the irrigation is running overnight. That matters a lot given what just happened to the tariff.
| ICP | Site | Share | kWh/yr | Notes |
|---|---|---|---|---|
| 0000535612NR7A3 | Club House | 70.9% | 97,911 | Anytime only — the main target |
| 0000535511NR860 | Pumps | 22.5% | 31,106 | 87% controlled — irrigation |
| 0000557358NR38A | Greenkeepers | 6.5% | 9,013 | Anytime only — small |
Solar on one ICP only offsets that ICP. Whether this becomes one system, three, or a consolidation is a live design decision — needs the physical layout confirmed on site.
Energy is up about 8%. The fixed daily charge is up 154%, and the controlled-rate discount has been removed entirely — night power now costs the same as day power.
Build the proposal on roughly $43,000/yr, not $36,500. Modelling savings off last year's rates would understate the case by about a fifth.
Check this on Thursday before it goes in a proposal. A 154% fixed-charge jump is big enough that it could be a plan change, a network reclassification, or a one-off rather than the new normal. Get Ejaaz to confirm the June bill is what he'll keep paying.
Losing the controlled rate means the irrigation pumps no longer get cheap power overnight — they now pay full daytime price to run at night. Shifting irrigation into daylight hours to run directly off the array turns roughly 31,000 kWh/yr of night consumption into self-consumed solar.
That's a scheduling change, not a hardware cost, and it's worth real money the moment the array is in. Confirm on site whether the irrigation timing is actually movable — greens watering is usually done at night for agronomic reasons, not just tariff ones.
| Period | Days | Club House | Greenkeepers | Pumps | Total kWh | kWh/day | $ incl GST |
|---|---|---|---|---|---|---|---|
| Aug 2025 | 24 | 7,307 | 750 | 546 | 8,603 | 358.5 | 2,304.32 |
| Sep 2025 | 37 | 8,895 | 999 | 1,187 | 11,081 | 299.5 | 2,975.26 |
| Oct 2025 | 31 | 8,361 | 684 | 2,752 | 11,797 | 380.6 | 3,042.31 |
| Nov 2025 | 30 | 8,533 | 635 | 3,449 | 12,617 | 420.6 | 3,201.25 |
| Dec 2025 | 31 | 8,614 | 696 | 3,935 | 13,245 | 427.3 | 3,340.96 |
| Jan 2026 | 31 | 8,994 | 690 | 3,513 | 13,196 | 425.7 | 3,351.76 |
| Feb 2026 | 28 | 8,198 | 618 | 3,854 | 12,670 | 452.5 | 3,181.59 |
| Mar 2026 | 31 | 8,377 | 734 | 3,988 | 13,099 | 422.5 | 3,295.50 |
| Apr 2026 | 30 | 7,252 | 752 | 1,675 | 9,680 | 322.6 | 2,550.60 |
| May 2026 | 31 | 7,711 | 766 | 2,074 | 10,552 | 340.4 | 2,760.05 |
| Jun 2026 | 30 | 7,354 | 924 | 1,490 | 9,767 | 325.6 | 3,459.81 |
| Total | 334 | 89,596 | 8,248 | 28,464 | 126,307 | 378.2 | 33,463.41 |
| Array | Generation | vs 138,030 kWh/yr load |
|---|---|---|
| 30 kW | ~42,000 kWh/yr | 30% |
| 50 kW | ~70,000 kWh/yr | 51% |
| 100 kW | ~140,000 kWh/yr | 101% |
Do not put these in front of the client. They are a sanity check on scale only, at a Northland yield of ~1,400 kWh/kWp/yr. Covering 100% of annual consumption does not mean a zero bill — it depends entirely on how much is self-consumed at the moment it's generated. The club house daytime baseload and the irrigation schedule decide the real number, which is why the site visit comes before the design.