Environmental Assessment on Energy and Sustainability by Data Envelopment Analysis
by Toshiyuki Sueyoshi, Mika Goto
21DESIRABLE AND UNDESIRABLE CONGESTIONS
21.1 INTRODUCTION
This chapter1 discusses the occurrence of congestion within the framework of DEA environmental assessment. As an extension of Chapter 9 on congestion, this chapter now separates the concept of congestion into undesirable and desirable categories in DEA environmental assessment. See Figures 9.1 to 9.4 for a visual description on an occurrence of congestion in a conventional context of DEA. After the separation, this chapter discusses how to measure an occurrence of desirable congestion (DC), or eco‐technology innovation, in comparison with that of undesirable congestion (UC). The concept of DC and UC has a close linkage with, respectively, returns to scale (RTS) and damages to scale (DTS) in Chapter 20. The comparison between Chapters 20 and 21 provides us with extended implications on RTS and DTS from an occurrence of the two types of congestion. The two chapters will be further conceptually and methodologically extendable into other scale measures in Chapter 23.
A concern of this chapter is that the identification of UC is indeed important for avoiding a cost increase and a shortage of transmission capacity in the case of the electric power industry, for example. However, the identification of DC is more important than that of UC in terms of our sustainable growth in which eco‐technology innovation can effectively reduce the amount of various types of pollution. Therefore, it is necessary for this chapter to discuss the occurrence ...