Technologies of Smart Grid - Smart Grid (R) Evolution: Electric Power Struggles - page 47

3 Technologies of Smart Grid
3.1 Multiple Technologies and Configurations
The term “smart grid” refers to more than a single technology or even a well-defined set
of individual technologies. It is an umbrella term under which multiple different electricity
system technologies, both hardware and software, are developing. As we mentioned in
Chapter 1 , for some smart grid is characterized primarily as the addition of an information
communication technology (ICT) overlay to existing infrastructure. For others, smart grid
represents the installation of new transmission lines, meters, and renewable generation. The
type and degree of technological change represented by smart grid varies among different
societalactors.Somepeopleviewsmartgridasaninevitable,alreadyoccurringevolutionary
upgrade to improve existing infrastructure and reinforce the existing system. Others view
smart grid as a future revolutionary shift in how electricity is generated, distributed, and
used, and a potentially destabilizing change that could shift power away from incumbent
actors. Recognizing the breadth of potential for both technical and social change, this
chapter focuses on reviewing smart grid technologies. This technology-focused chapter
connects basic engineering details with the promises and pitfalls outlined in Chapter 2 . The
chapter also provides technological background helpful for understanding the details of the
subsequent chapters.
To represent the complexity of smart grid development, we first offer a brief description
of existing electricity systems (we have labeled these “legacy systems”). We then highlight
smart grid technologies and the parts of the legacy systems in which integration of these
technologies has the potential to contribute to achieving the smart grid promises introduced
in Chapter 2 .
We begin by describing the dominant current centralized, fossil fuel-based electricity
systems - that is, the legacy systems from which smart grid systems are evolving.
Familiarity with the basic structure and function of today's electricity systems is critical
to understand how emerging smart grid technologies might change the electricity system's
function and structure. In the first half of this chapter, we present the conventional
technologies for electricity supply which follows a one-way, linear path from electricity
generation, to transmission, to distribution and use. In the second half of the chapter,
we introduce and explain prominent emerging smart grid technologies that could enable
new types of interactions and change legacy systems. Given the diversity and pace of