Electricity guide · New Zealand
Electricity Daily Charge vs kWh Rate NZ
Compare the fixed daily charge and variable cents-per-kWh rate on a New Zealand power plan, calculate annual fixed cost and assess total bill scenarios.
Reviewed 26 August 2026
Reviewed by KiwiTools editorial team — NZ energy researchers using Electricity Authority and EECA sources
General planning information. Electricity prices, time bands, appliance performance and solar export terms vary by address, retailer, installation and usage.
Key points
Two major electricity price components
Daily fixed cost = daily charge × number of connected days.
Variable usage cost = kWh used × applicable dollars per kWh.
The plan with the lowest kWh price is not necessarily cheapest when its daily charge and the household’s usage are included.
Where two plans break even
Plan A charges $0.60 more each day but 6 cents less per kWh. Divide the annual fixed-cost difference by the usage-rate saving.
| Check | Daily charge | Usage rate | Annual cost at 3,650 kWh |
|---|---|---|---|
| Plan A | $1.50/day | $0.24/kWh | $1,423.50 |
| Plan B | $0.90/day | $0.30/kWh | $1,423.50 |
| Below 3,650 kWh | Higher fixed cost hurts | Plan B tends cheaper | Depends on actual use |
| Above 3,650 kWh | Fixed cost diluted | Plan A tends cheaper | Depends on actual use |
A cheap unit rate can hide an expensive connection
Plan A might charge $1.50 a day and 24 cents per kWh; Plan B, 90 cents a day and 30 cents. The first costs $219 more a year before a single unit is used, but saves 6 cents on every kWh.
They break even at 3,650 kWh. Below that, Plan B tends to win; above it, Plan A tends to. This is arithmetic, not a “low-user” label.
Use a full year of your own consumption
Winter-heavy homes can look cheap in a summer-only comparison. Add at least 12 months of kWh and the exact days in the period, then include every recurring credit or fee.
Promotional discounts should expire in the model when they expire in real life. A first-month credit is not a permanent reduction in the daily charge.
Related: how to read power bill Related: peak off peak electricity rates Related: electricity rate per kwh
Solar does not make the fixed charge vanish
Panels can reduce imported kWh and create export credits, but a grid-connected home may still pay the daily charge. Lower imports can therefore push the household toward a plan with lower fixed cost even when its unit rate is higher.
Compare import and export prices together. Choosing on buy-back rate alone can lose more on purchased electricity than it gains from exported solar.
Frequently asked questions
How much does a daily power charge cost per year?
Multiply the dollars-per-day charge by 365 for a full connected year.
Is a lower kWh rate always cheaper?
No. A higher daily charge or different time-of-use prices can make the total bill higher.
Does the daily charge change with usage?
It is normally applied per connected day rather than per kWh, subject to the plan terms.
How should I compare two NZ power plans?
Apply both plans to the same actual usage profile, days, time periods, fixed charges, discounts and fees.
Put the guide into practice
Continue with related KiwiTools calculators
Test your own numbers, compare scenarios and return to the guide to check assumptions and limitations.