Peak and off-peak lighting cost notes
Peak and off-peak lighting cost compares the same lighting load under two user-entered period and rate assumptions.
Peak/off-peak sequence
Keep one lighting load fixed, then split the day into two period blocks with their own rates.
- 1Enter the load
Use the same connected load for both periods.
- 2Set the peak block
Enter peak hours and the peak rate.
- 3Set the off-peak block
Enter off-peak hours and the off-peak rate.
- 4Add the annual days
Use the number of days the split repeats.
- 5Read the total cost
Keep the two period lines visible.
Application estimate fit
Match the search phrase to one lighting load, period and assumption set before reading the result.
| Search phrasing | Calculator case | Carry forward |
|---|---|---|
| Peak and off-peak lighting cost | One lighting load with two daily periods and two rates. | Peak cost, off-peak cost and total cost. |
| Split-period site note | A site that uses different rates for different hours. | Keep the periods and rates visible together. |
| Day and night comparison | One lighting group with day and night assumptions. | Peak kWh and off-peak kWh shown as two lines. |
| Mixed schedule case | A load whose hours are split across two price periods. | Keep the same connected load for both periods. |
Reading the result
Each output belongs to a bounded lighting energy estimate and should travel with its assumptions.
| Output | Technical meaning | Review item |
|---|---|---|
| Total annual cost | Peak cost plus off-peak cost. | Keep both periods visible before comparing totals. |
| Peak cost | Peak kWh multiplied by the peak rate. | This is the peak-period cost line. |
| Off-peak cost | Off-peak kWh multiplied by the off-peak rate. | This is the off-peak cost line. |
| Peak kWh | Connected load multiplied by peak hours and days. | Peak-period energy only. |
| Off-peak kWh | Connected load multiplied by off-peak hours and days. | Off-peak-period energy only. |
Assumptions that stay visible
Small changes in load, hours, rate or factor can move the result, so the assumptions stay beside the number.
| Assumption | Why it matters | Where it belongs |
|---|---|---|
| Peak hours | The daily hours assigned to the peak period. | Keep the period visible. |
| Off-peak hours | The daily hours assigned to the off-peak period. | Keep the period visible. |
| Rates | Each period uses a user-entered rate. | Write both rates beside the result. |
| Days per year | The same split period repeats through the year. | Change the days if the pattern is seasonal. |
split-period lighting group before the number
A useful peak and off-peak lighting cost estimate begins with the exact split-period lighting group, not a whole-site average. The same building can include reception lights, display lights, warehouse aisles, amenity rooms and exterior signs that all run for different hours. Naming the group keeps the load, hours and money value tied to one visible lighting job.
That boundary also makes later revision easier. If the fittings, scene level or operating period changes, the row can be revised without rebuilding unrelated areas. Write the space name, fitting family and control group beside the result so another person can check the same case later.
Connected load remains the anchor
Energy and cost estimates move when connected load changes. Count the fittings or enter the load that belongs to the named group, then keep the wattage basis visible. Complete fitting input watts are stronger than a bare lamp value because drivers, control gear and luminaire packages can change the actual load.
The connected-load note does not prove the light level is suitable. A lower load can still be too dim, glary or uneven, while a higher load may support a harder task. Keep lux, beam, colour and measured-light pages nearby when the lighting quality also needs checking.
Hours carry much of the movement
Peak and off-peak daily hours can move the annual result more than a small wattage change. Seven-day corridors, hospitality scenes, office task rows, seasonal stores and after-hours security lights may all have different operating patterns even when the fittings look similar.
Enter the hours for the same lighting group named in the result. If the group has a normal scene and an after-hours scene, split those cases rather than hiding both in one average. A tidy input line with hours, days and control state is easier to revise than a single unexplained total.
Controls change energy without changing installed load
The same load across two price periods can reduce energy by shortening operating time or lowering average output. Occupancy sensing, daylight dimming, timeclocks, scene presets and holiday shutdowns all change the energy case while the installed wattage may remain the same.
Keep full connected load and controlled operation visible as different ideas. That separation lets a user compare the installed capacity, the normal operating case and the reduced-energy case without implying that the electrical installation has changed.
Rates and factors are user-entered assumptions
Two user-entered rates belongs beside the result because it can change while the lighting kWh stays fixed. A rate comparison, carbon estimate or simple payback note is only as current as the entered cents per kWh, emissions factor or annual saving value.
For Australian lighting notes, keep the rate date, account basis or factor source in the project file if the result will be reused. This page keeps the arithmetic transparent; it does not choose an electricity plan, account structure, rebate or finance outcome.
Read comparisons as bounded arithmetic
Peak versus off-peak period cost is helpful when the two cases share the same lighting group and schedule basis. Rate A and Rate B, old hours and new hours, or full output and dimmed output should describe the same load before the numbers are compared.
A comparison can show the size of a difference, but it does not decide whether the lighting change is appropriate. Light level, comfort, controls, maintenance access and site operating needs still need their own notes when they affect the decision.
Monthly, annual and period values are different
Monthly values are useful for a short period or a local cost note. Annual values are useful for longer operating schedules, carbon factors and simple payback. After-hours and shutdown values describe only the named period, not the whole lighting account.
Keep the period wording in the result. A monthly cost, an annual kWh value and a holiday shutdown saving should not be compared until the period, hours and days have been made consistent.
Australian energy estimate limits
peak and off-peak lighting cost pages on AuLumens are planning estimates for lighting load, kWh, user-entered cost rates, carbon factors or simple payback. They do not model demand items, metered account totals, rebates, tax treatment, electrical design, emergency lighting or certification.
It is a period-cost estimate, not energy-plan guidance or an account forecast. Keep account-specific charges, landlord agreements, emissions reporting basis and electrical installation details in the appropriate site file. The value of the lighting estimate is that it records the load, period and assumptions before those wider checks begin.
A concise calculation note
A readable note includes the lighting group, connected load, operating period, output state, user-entered rate or factor, and whether the result is monthly, annual or limited to a named period. For split cases, include both sides of the comparison.
Keep monthly running cost and rate comparison pages nearby when the same group also needs a simpler rate note. That context makes the result practical. Another person can change the hours, revise the rate, adjust the control state or compare the result with measured energy data without guessing how the original number was produced.