Page 7 - From Smart Grid to Internet of Energy

2 From smart grid to internet of energy

This big picture has promoted improvement and enhancement of Smart Grid by
two brilliant idea: two-way flow of power and communication signals. The
Smart Grid can be summarized by these two contributions if we want to explain
in the widest sense. However, to obtain a power grid with two-way power flow
and two-way communication infrastructure is much more complicated than
summarizing with a few words. The Smart Grid architecture requires wide-
spread technologies for each infrastructure of generation, transmission, distri-
bution, and consumers. The distributed generation and microgrid concepts
are the most prominent concepts supporting to accomplish two-way power flow
task. Therefore, consumers can be converted to prosumers that do not only con-
sume the energy but also participate to power generation by constructing their
own distributed generation plants with several micro sources such as renewable
energy sources (RESs), energy storage systems (ESSs), and conventional gen-
eration plants and so on. Inevitably, communication technologies are involved
for measurement, monitoring, and control aims in such a scenario where the
prosumers either consume or generate. These improvements are assumed as
the most important contributions of intelligent systems to existing power grid
to comprise the Smart Grid concept [1].
In the early times of Smart Grid researches, it has announced with several
names such as intelligent grid, future grid, intelligrid, and intergrid by different
research groups [2]. However, Smart Grid has been widely accepted and
assumes as a standard definition of this new power grid technology [1]. It will
be useful to remember some perspectives of conventional grid before describing
Smart Grid infrastructure.
The traditional power grid is comprised by four main infrastructures which
are generation, transmission, distribution and consumption layers. This infra-
structure is survived by large generation plants that are installed at several
MW power levels, and it is connected to a transmission substation where the
transmission system is get started [3]. The transmission line is responsible
for delivering required power to distribution substations to feed the generated
power to several distribution networks. Consequently, the connection between
generation and consumption layers is managed by the intermediate layers. The
typical transmission systems are designed to operate in large voltage operating
voltage levels ranging from 150 to 765 kV while the distribution networks oper-
ate at 11–110 kV voltage ranges. The traditional power grid is unidirectional in
terms of power flow since distributed generation (DG) sources have not been
allowed to participate in this system. Moreover, the electricity price is deter-
mined by utility system operators where customers had no chance to choose
their electricity tariff [4].
On the contrary to increasing demand and consumption rates, the central
generation approach used in traditional power grid was not sufficient to meet
the requirements of growing societies. In addition to generation, the control pro-
cess of traditional grid was not appropriate for the aging power networks since it
has been installed according to manual monitoring and manual restoration
approaches due to limited control ability [2]. The schematic diagram of