ABSTRACT
Every T&D plan is based on a load forecast, whether it is only a vague, informal idea in the mind of the planner, or a detailed projection produced by a computer program. The load forecast defines the “T&D planning problem,” and, as the first step in the planning process, is in many ways the most important. A poor load forecast will mislead the planner, causing him to design the wrong type of system expansion plan. By contrast, a good forecast simplifies his job, showing the planner what needs to be done in the future expansion of the power delivery system facilities. This chapter discusses distribution load, how it grows, and how it “looks” when examined for T&D planning and engineering purposes. It is the first of two that will focus on the spatial aspects of load forecasting, as opposed to temporal (Chapter 2-4) and weather-related factors (Chapters 5-6). A thorough understanding of spatial behavior is critical not only to forecasting, but to planning in general: Know your enemy
A point stressed in this chapter is that when viewed at the small area level, load growth trends can look substantially different than when viewed at the system level. The reasons this occurs, and the manner in which this phenomenon shapes the way T&D loads must be forecast, are among the most important concepts covered in this chapter.
