Electrical Load Factors for building load calculations

6Preliminary Load Calculations

6.1.0 Introduction6.1.1 Prescriptive Unit Lighting Power Allowance (ULPA) (W/ft2), Gross

Lighted Area of Total Building6.1.2 Typical Appliance/General-Purpose Receptacle Loads (Excluding

Plug-In-Type A/C and Heating Equipment)6.1.3 Typical Apartment Loads6.1.4 Typical Connected Electrical Load for Air Conditioning Only6.1.5 Central Air Conditioning Watts per SF, BTUs per Hour per SF of Floor

Area, and SF per Ton of Air Conditioning6.1.6 All-Weather Comfort Standard Recommended Heat-Loss Values6.1.7 Typical Power Requirement (kW) for High-Rise Building Water

PressureBoosting Systems6.1.8 Typical Power Requirement (kW) for Electric Hot WaterHeating System6.1.9 Typical Power Requirement (kW) for Fire Pumps in Commercial

Buildings (Light Hazard)6.1.10 Typical Loads in Commercial Kitchens6.1.11 Comparison of Maximum Demand6.1.12 Connected Load and Maximum Demand by Tenant Classification6.1.13 Factors Used in Sizing Distribution-System Components6.1.14 Factors Used to Establish Major Elements of the Electrical System

Serving HVAC Systems6.1.15 Service Entrance Peak Demand (Veterans Administration)6.1.16 Service Entrance Peak Demand (Hospital Corporation of America)

6.1.0 IntroductionThe following tables are provided to assist the user in estimating preliminaryloads for various building types. Considerable judgment should be used in theapplication of these data. Power densities typically are given in watts per squarefoot (W/ft2) or volt-amperes per square foot (VA/ft2) and are used interchangeablybecause unity power factor is assumed for preliminary load calculations.

These tables give estimated connected loads. To these the user must apply ademand factor to estimate the actual demand load. Demand factors for buildingstypically range between 50 and 80 percent of the connected load. For most buildingtypes, the demand factor at the service where the maximum diversity is experiencedis usually 60 to 75 percent of the connected load. Specific portions of the system mayhave much higher demand factors, even approaching 100 percent.

Section

6.1

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6.1.1 Prescriptive Unit Lighting Power Allowance(ULPA) (W/ft2), Gross Lighted Area of Total Building

6.2 Section Six

TABLE 6.1.1

TABLE 6.1.2

6.1.2 Typical Appliance/General-PurposeReceptacle Loads (Excluding Plug-In-TypeA/C and Heating Equipment)

(From IEEE Std. 241-1990. Copyright 1990 IEEE. All rights reserved.)

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Preliminary Load Calculations 6.3

6.1.3 Typical Apartment Loads

TABLE 6.1.3

TABLE 6.1.4

6.1.4 Typical Connected ElectricalLoad for Air Conditioning Only



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6.1.5 Central Air Conditioning Watts per SF,BTUs per Hour per SF of Floor Area, andSF per Ton of Air Conditioning

6.4 Section Six

TABLE 6.1.5

TABLE 6.1.6

6.1.6 All-Weather Comfort StandardRecommended Heat-Loss Values


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6.1.8 Typical Power Requirement (kW)for Electric Hot WaterHeating System


TABLE 6.1.7

TABLE 6.1.8

TABLE 6.1.9

6.1.7 Typical Power Requirement (kW) for High-Rise Building Water PressureBoosting Systems

6.1.9 Typical Power Requirement (kW) for FirePumps in Commercial Buildings (Light Hazard)




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6.1.10 Typical Loads in Commercial Kitchens

6.6 Section Six

TABLE 6.1.10

TABLE 6.1.11

Note: As an alternative to the preceding table, you may use 25 W/ft2 forcommercial kitchens using natural gas for cooking or 125 W/ft2 for electriccooking. The applicable square footage in calculating kitchen floor areashould include cooking and preparation, dishwashing, storage, walk-inrefrigerators and freezers, food serving lines, tray assembly, and offices.

6.1.11 Comparison of Maximum Demand



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6.1.12 Connected Load and MaximumDemand by Tenant Classification


TABLE 6.1.12

TABLE 6.1.13

6.1.13 Factors Used in SizingDistribution-System Components



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6.1.14 Factors Used to Establish Major Elements ofthe Electrical System Serving HVAC Systems

6.8 Section Six

TABLE 6.1.14

TABLE 6.1.15

Note: For a primary cooling system comprised of electrical centrifugalchillers, chilled water pumps, condenser water pumps, and cooling towerfans, a factor of 1.7 kVA/ton provides a good estimate.



6.1.15 Service Entrance Peak Demand(Veterans Administration)

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6.1.16 Service Entrance Peak Demand(Hospital Corporation of America)


TABLE 6.1.16


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Front MatterTable of Contents6. Preliminary Load Calculations6.1.0 Introduction6.1.1 Prescriptive Unit Lighting Power Allowance (ULPA) (W/ft2), Gross Lighted Area of Total Building6.1.2 Typical Appliance/General-Purpose Receptacle Loads (Excluding Plug-In-Type A/C and Heating Equipment)6.1.3 Typical Apartment Loads6.1.4 Typical Connected Electrical Load for Air Conditioning Only6.1.5 Central Air Conditioning Watts per SF, BTUs per Hour per SF of Floor Area, and SFper Ton of Air Conditioning6.1.6 All-Weather Comfort Standard Recommended Heat-Loss Values6.1.7 Typical Power Requirement (kW) for High-Rise Building Water Pressure - Boosting Systems6.1.8 Typical Power Requirement (kW) for Electric Hot Water - Heating System6.1.9 Typical Power Requirement (kW) for Fire Pumps in Commercial Buildings (Light Hazard)6.1.10 Typical Loads in Commercial Kitchens6.1.11 Comparison of Maximum Demand6.1.12 Connected Load and Maximum Demand by Tenant Classification6.1.13 Factors Used in Sizing Distribution-System Components6.1.14 Factors Used to Establish Major Elements of the Electrical System Serving HVAC Systems6.1.15 Service Entrance Peak Demand (Veterans Administration)6.1.16 Service Entrance Peak Demand (Hospital Corporation of America)

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Electrical Load Factors for building load calculations