Commercial Tenant Load Calculator

A commercial tenant load calculation establishes the tenant’s connected load and applies a previously reviewed demand factor to produce an entered-demand tenant load. That demand-load figure is commonly carried into a tenant fit-out load review, preliminary feeder planning, panelboard capacity review, and coordination with building-management or landlord electrical capacity information.

Related tools: Commercial Load Calculator, Commercial Receptacle Demand Calculator, and Commercial Retail Load Calculator.

The calculator sums five entered load groups:

• Lighting load (kW)
• Receptacle load (kW)
• HVAC load (kW)
• Process load (kW)
• Kitchen load (kW)

It then applies the Entered tenant demand factor (%) and compares the result with the Entered tenant capacity (kW).

The calculator produces three values:

Result	Electrical use
Connected tenant load	Total nameplate or estimated connected load entered for the tenant worksheet
Entered-demand tenant load	Connected load after application of the reviewed tenant demand factor
Tenant capacity margin	Remaining entered capacity after the entered-demand tenant load is deducted

Connected Tenant Load

Connected tenant load is the arithmetic sum of the entered tenant load groups. It represents the full kW total entered into the worksheet before diversity, operating schedule, or any reviewed demand treatment is applied.

\(\displaystyle \text{Connected tenant load (kW)} = \text{Lighting load} + \text{Receptacle load} + \text{HVAC load} + \text{Process load} + \text{Kitchen load}\)

For a commercial space, these load categories can support early electrical distribution planning:

• Lighting load contributes to branch-circuit and lighting-panel load review.
• Receptacle load represents general-use utilization equipment or receptacle demand assigned to the tenant.
• HVAC load captures tenant mechanical electrical demand entered for the worksheet.
• Process load covers equipment associated with the tenant’s business operation.
• Kitchen load identifies food-service or kitchen equipment demand entered separately from other process equipment.

The connected total is not an ampacity result. Converting kW to amperes requires the actual system voltage, phase arrangement, power factor where applicable, and load characteristics. Those conditions are not entered in this tenant-load worksheet.

Entered Tenant Demand Factor

The Entered tenant demand factor (%) reduces the connected tenant load by a factor that has already been reviewed outside the calculator.

\(\displaystyle \text{Entered-demand tenant load (kW)} = \text{Connected tenant load} \times \left(\frac{\text{Entered tenant demand factor}}{100}\right)\)

A demand factor reflects the reviewed assumption that not every connected load will operate at its full connected value at the same time. The calculator applies one entered percentage to the entire tenant connected load; it does not assign separate demand factors to lighting, receptacle, HVAC, process, or kitchen loads.

Use the entered factor only after the underlying load grouping and demand basis have been established. A tenant with substantial HVAC, kitchen equipment, continuous process equipment, or unusual operating hours may require a different reviewed basis than a general office tenant.

Tenant Capacity Margin

Tenant capacity margin compares the entered tenant capacity against the entered-demand tenant load.

\(\displaystyle \text{Tenant capacity margin (kW)} = \text{Entered tenant capacity (kW)} - \text{Entered-demand tenant load (kW)}\)

A positive margin indicates that the entered capacity exceeds the calculated demand load. A zero margin indicates that the demand load equals the entered capacity. A negative margin indicates that the entered-demand load is greater than the capacity supplied for comparison.

The result is useful during preliminary coordination of tenant electrical capacity, but it does not establish feeder ampacity, overcurrent protection, service capacity, or available panelboard spaces. Those decisions require the actual electrical distribution configuration and applicable design criteria.

Calculation Example

Enter the following tenant loads:

Input	Entered value
Lighting load (kW)	12
Receptacle load (kW)	8
HVAC load (kW)	20
Process load (kW)	6
Kitchen load (kW)	4
Entered tenant demand factor (%)	80
Entered tenant capacity (kW)	45

First, sum the entered load groups:

\(\displaystyle 12 + 8 + 20 + 6 + 4 = 50 \text{ kW}\)

Connected tenant load = 50 kW

Next, apply the entered 80% tenant demand factor:

\(\displaystyle 50 \text{ kW} \times 0.80 = 40 \text{ kW}\)

Entered-demand tenant load = 40 kW

Finally, compare the demand load with the entered tenant capacity:

\(\displaystyle 45 \text{ kW} - 40 \text{ kW} = 5 \text{ kW}\)

Tenant capacity margin = 5 kW

In this example, the entered comparison capacity exceeds the demand-adjusted tenant load by 5 kW. That result can be carried into a preliminary tenant-capacity discussion before completing the applicable feeder, service, and equipment sizing work.

Feeder and Distribution Review

The tenant-load result can be a starting point for evaluating the electrical path serving the space, including a tenant feeder, panelboard, distribution section, or landlord-provided electrical capacity. The kW result must be translated into the actual electrical system conditions before conductors, raceways, and protective devices are selected.

A complete design or field review may require verification of:

• System voltage, phase, and whether the served load is single-phase or three-phase
• Actual equipment nameplate data and operating characteristics
• Continuous-load treatment where applicable
• Branch-circuit and feeder loading assumptions
• Motor and HVAC load treatment, including associated starting and running characteristics
• Conductor AWG or kcmil selection, terminal rating, insulation temperature rating, correction factor, and adjustment factor
• Number of current-carrying conductors in a raceway and resulting conductor adjustment requirements
• Raceway fill, conduit routing, pull points, bends, and physical installation constraints
• Voltage-drop performance from the source to the tenant distribution equipment and major loads
• Available equipment capacity, interrupting requirements, and coordination with the building electrical system
• AHJ, engineer, owner, landlord, utility, and lease-load approval requirements

A positive tenant capacity margin does not by itself confirm that an existing feeder has adequate ampacity or that an existing conduit has adequate raceway fill. It also does not confirm that voltage drop, conductor termination ratings, panelboard ratings, overcurrent protection, or available fault-current conditions are acceptable.

Calculation Boundary

This commercial tenant load worksheet performs tenant worksheet arithmetic only. It sums the entered load groups, applies the entered tenant demand factor, and compares the result with the entered tenant capacity.

It does not select a demand factor, classify occupancy, apply a code demand method, size branch circuits or feeders, determine conductor ampacity, calculate voltage drop, evaluate raceway fill, size a service, or approve tenant electrical capacity. Review those electrical and code decisions separately using the actual project documents, equipment data, installation conditions, and requirements of the AHJ.