Supply capacity planning calculator
Compare entered available supply with present demand, future loads and allowance records for Australian capacity planning.
Iplanned = Iexisting + Ifuture + Iallowance; RemainingA = Isupply - Iplanned; UsedPercent = Iplanned / Isupply x 100; ReservePercent = RemainingA / Isupply x 100; reserve_margin = ReservePercent - ReserveTarget- Available supply is entered by the user.
- Future load and allowance values must use the same current basis.
- The reserve target is a worksheet comparison value.
- The calculator does not decide network or switchboard suitability.
| Variable | Meaning | Unit | Use |
|---|---|---|---|
| Isupply | Available supply | A | Entered supply capacity comparison value. |
| Iexisting | Existing demand | A | Entered present demand record. |
| Ifuture | Committed future load | A | Entered known future load allowance. |
| Iallowance | Planning allowance | A | Entered additional allowance carried in the plan. |
| Iplanned | Planned load | A | Sum of existing demand, future load and allowance. |
| RemainingA | Remaining capacity | A | Available supply minus planned load. |
| ReservePercent | Reserve capacity | % | Remaining capacity divided by available supply. |
| ReserveTarget | Minimum reserve target | % | Entered reserve comparison value. |
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Supply capacity planning calculator technical guide
Compare entered available supply with present demand, future loads and allowance records for Australian capacity planning.
Use this calculator when a site, tenancy, board group or project stage needs a high-level capacity worksheet that includes existing demand, committed future load and a separate planning allowance. The page keeps those values apart so the reserve result can be checked later.
Field Use Cases
| Work setting | Real question | Useful action from this page |
|---|---|---|
| Site planning | How much entered capacity remains after present and future loads? | Sum existing demand, committed load and allowance. |
| Tenancy fit-out | Does the entered reserve stay above the worksheet target? | Compare reserve percentage with the entered target. |
| Future load review | Which allowance is driving the margin? | Keep future load and planning allowance separate. |
| Board upgrade discussion | Is the issue a supply value or a board value? | Route board-specific checks to spare switchboard capacity. |
| Staged work | Which future loads should be staged next? | Move stage-by-stage questions to the staged load calculator. |
This page is not a network capacity decision. It is a record of how entered planning values compare.
Data checklist
| Value | Where it normally comes from | Stop if |
|---|---|---|
| Available supply | Project record, design basis, measured record or supply note | The comparison value has no owner. |
| Existing demand | Maximum-demand worksheet, measured record or load schedule | Existing demand uses a different current basis. |
| Committed future load | Approved project scope, equipment list or design allowance | The future load is speculative but not labelled. |
| Planning allowance | Engineering or estimating allowance | It is being hidden inside existing demand. |
| Reserve target | Project review value | The target has no source basis. |
The worksheet works best when the available supply value and all load values are current-based and comparable.
Review Workflow
| Step | Record to check | Move to |
|---|---|---|
| Define the supply boundary | Site, tenancy or switchboard group reference | Enter available supply. |
| Confirm present demand | Maximum-demand or measured record | Enter existing demand. |
| Separate future loads | Committed load and planning allowance | Read planned load. |
| Compare reserve | Minimum reserve percentage | Check review status. |
| Choose detailed check | Board capacity, maximum demand or staged additions | Use the linked calculator that owns that question. |
If reserve capacity is below the entered target, treat it as a source-review prompt. It does not identify the only project response.
Worked capacity record
A project worksheet enters 400 A available supply, 210 A existing demand, 65 A committed future load and a 35 A planning allowance. The minimum reserve target is 15%.
The planned load is 310 A, leaving 90 A remaining capacity. The used capacity is 77.5% and the reserve is 22.5%. The reserve margin is 7.5 percentage points above the entered target.
| Value | Result |
|---|---|
| Available supply | 400 A |
| Planned load | 310 A |
| Remaining capacity | 90 A |
| Used capacity | 77.5% |
| Reserve capacity | 22.5% |
| Reserve margin | 7.5% |
The result is a useful planning record because the present and future loads remain separated. If the future load changes, the worksheet can be updated without reworking the entire project note.
Method boundary
| Method element | What this page does | What remains outside |
|---|---|---|
| Planned load | Adds existing demand, committed future load and planning allowance. | Selecting the demand method or future-load basis. |
| Remaining capacity | Subtracts planned load from entered available supply. | Confirming actual network or board capacity. |
| Reserve percentage | Divides remaining capacity by entered supply value. | Deciding project suitability. |
| Reserve margin | Compares reserve with the entered target. | DNSP, project and equipment review. |
Keeping the method this narrow helps the page support planning without overreaching into network, switchboard or project decisions.
Stop points
- The available supply value has no source record.
- Existing demand, future load and allowance values use different current bases.
- Future loads are speculative but not labelled as an allowance.
- The reserve target is copied without project context.
- The result is being used as a network or switchboard decision.
- Board-specific capacity, maximum demand or staged additions need their own worksheet.
When a stop point appears, keep the exported result as a planning question and resolve the source value before carrying the reserve margin downstream.
Site supply planning record
A site supply worksheet combines existing demand, committed load and an entered planning allowance.
- Supply reference
- SUPPLY-1
- Available supply
- 400 A
- Minimum reserve
- 15%
- Planned load310 A
- Remaining capacity90 A
- Reserve22.5%
Use the status as a capacity-planning prompt before formal supply review.
The reserve remains above the entered target, so the record can be carried into board and demand review.
- Available supply is entered by the user.
- Future loads use the same current basis.
- DNSP and project requirements remain outside the arithmetic.
Constrained allowance review
A larger planning allowance reduces reserve below the entered target.
- Supply reference
- SUPPLY-REVIEW
- Available supply
- 400 A
- Minimum reserve
- 15%
- Planned load355 A
- Remaining capacity45 A
- Reserve11.25%
Use the status as a capacity-planning prompt before formal supply review.
The reserve result is below the target, so source values and supply assumptions need review.
- The reserve target is entered by the user.
- The worksheet does not decide connection capacity.
- Demand calculation remains a separate task.
Small tenancy supply record
A tenancy fit-out compares present load with a smaller committed allowance.
- Supply reference
- TENANCY-SUPPLY
- Available supply
- 160 A
- Minimum reserve
- 20%
- Planned load100 A
- Remaining capacity60 A
- Reserve37.5%
Use the status as a capacity-planning prompt before formal supply review.
The remaining reserve stays above the entered target for this planning worksheet.
- Loads are entered as planning current values.
- Supply capacity is a comparison value.
- Switchboard spare capacity should be checked separately.