Street and Exterior Lighting

MIL-HDBK-1133

Loads defined as unusual will typically be found as

motor loads, resistance electric loads, or process steam or hot

water loads. Estimating these loads can be a straightforward

calculation of operating rate or capacity multiplied by the hours

of operation. However, in many cases the hours of operation are

not well known. The rate or capacity of equipment can also be

hard to identify accurately. In the case of constant loads such

as strip heaters or single-level steam appliances, the nameplate

rating expressed in energy per hour can be considered an

appropriate value. For motors and other induction loads, the

actual consumption rate value will depend on actual loading of

the equipment. This loading will vary greatly and may be

difficult to quantify. In most cases, the nameplate values will

be a maximum that is not often achieved. Estimates of these

unusual loads must be added to the total energy consumption value

derived for the typical building with which it is associated. To

estimate each load, the following steps can be used:

a) Identify the nameplate or other value of capacity.

If part-load or other actual operational conditions that affect

actual energy draw can be determined, they should be taken into

consideration.

b)

Determine the number of hours of operation.

c) Calculate consumption by multiplying consumption

rate by time.

d) Add this value to the electric or nonelectric total

as appropriate.

2.5

Street and Exterior Lighting. Street and exterior

lighting is defined to be any exterior lighting other than that

typically found around a building. Therefore, normal

safety/security lighting (e.g., lighting over doorways and

entrances; porch lights) is not typically considered exterior.

Lighting in parking areas, security lighting, or floodlighting

for outdoor work at night are typically considered exterior. The

energy this lighting consumes is not usually assigned to specific

buildings or activities and is often accounted for separately.

The determination of whether this energy use is

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