II. COMMUNICATIONS TECHNOLOGIES AVAILABLE
FOR SMART GRIDS
A communications system is the key component of the smart
grid infrastructure [1], [14], [16]. With the integration of advanced
technologies and applications for achieving a smarter
electricity grid infrastructure, a huge amount of data from different
applications will be generated for further analysis, control
and real-time pricing methods. Hence, it is very critical
for electric utilities to define the communications requirements
and find the best communications infrastructure to handle the
output data and deliver a reliable, secure and cost-effective service
throughout the total system. Electric utilities attempt to get
customer’s attention to participate in the smart grid system, in
order to improve services and efficiency. Demand side management
and customer participation for efficient electricity usage
are well understood, furthermore, the outages after disasters in
existing power structure also focus the attention on the importance
of the relationship between electric grids and communications
systems [1].
Different communications technologies supported by two
main communications media, i.e., wired and wireless, can be
used for data transmission between smart meters and electric
utilities. In some instances, wireless communications have
some advantages over wired technologies, such as low-cost
infrastructure and ease of connection to difficult or unreachable
areas. However, the nature of the transmission path may cause
the signal to attenuate. On the other hand, wired solutions
do not have interference problems and their functions are not
dependent on batteries, as wireless solutions often do.
Basically, two types of information infrastructure are needed
for information flowin a smart grid system. The first flowis from
sensor and electrical appliances to smart meters, the second is
between smart meters and the utility’s data centers. As suggested
in [17], the first data flow can be accomplished through
powerline communication or wireless communications, such as
ZigBee, 6LowPAN, Z-wave, and others. For the second information
flow, cellular technologies or the Internet can be used.
Nevertheless, there are key limiting factors that should be taken
into account in the smart metering deployment process, such
as time of deployment, operational costs, the availability of the
technology and rural/urban or indoor/outdoor environment, etc.
The technology choice that fits one environment may not be
suitable for the other. In the following, some of the smart grid
communications technologies along with their advantages and
disadvantages are briefly explained. An overview of smart grid
communication technologies can be found in Table I.