IEEE Electrification Magazine - June 2018 - 43

often takes place. In addition, relatively low efficiency in energy consumption and power system facilities utilization is
also a big problem. energy consumption per unit of gross
domestic product (gdP) in china was about twice the
world's average in 2011, and the utilization rate of the power transmission and distribution systems is less than 50%
and 30%, respectively. Meanwhile, to address increasing environmental concerns, the chinese government has promised that carbon emissions and energy consumption per
unit of gdP will both be reduced by 40% by 2020, with the
carbon emissions peak in china coming at approximately 2030.

Three EI Features
the eI can be regarded as a future vision of the smart grid,
and what qualifies it for the latter term relies mainly on
the following three features:
1) Internet thinking will reshape the energy networks.
the eI will be constructed based on the synergy of
multienergy systems, including heating, cooling, gas,
transportation, and electricity. In the eI, it is essential
to remove the existing barriers, which can be imagined as walls between different energy sectors, and
produce new flexibility and achieve high efficiency by
better interconnection of these heterogeneous energy
subsystems. on that basis, energy routers, energy hubs, wireless energy transfer, dc networks, advanced energy storage, and plug-and-play techniques
will be utilized to build up an Internet-like energy
grid that will support better connections between
supply and demand.
2) Internet methodologies, such as cloud computing, big
data, the Internet of things (Iot), blockchains, and so
on will also empower the energy network with more
smartness and openness.
3) new business models and energy markets based on
the sharing economy will be designed with widespread involvement of energy prosumers. the eI will
be realized to enable complex interactions among
multiple participants in not only energy transactions
but also diverse services.
Because of its potential to overcome difficulties and
challenges in reforming the chinese energy industry and
to realize a truly interconnected energy system, the eI
may become one of the most important research topics in
future decades. For instance, the chinese government has
initiated a series of power market deregulation reforms to
improve the competitiveness and efficiency of the energy
markets. also, several eI-related research plans and demonstration projects have been funded by the chinese government, aimed at improving bottom-up innovations in
scientific research and practical applications in and
between different energy systems.
the vision and scope of the eI partially overlaps some
related concepts-e.g., energy system integration or integrated energy system-proposed by U.S. and european

researchers in terms of dovetailing different energy systems. In addition, however, the emphasis in the eI
includes Internet thinking and technologies to optimize
overall system operation based on linking energy networks. therefore, the eI's scope promotes the interconnection, openness, sharing, and coordination of various
energy resources and to shape a green, low-carbon, efficient, and low-cost energy ecosystem.
the concept and contents of the eI have been discussed and extended by many researchers globally for
years. as early as 2008, a group of scientists from north
carolina State University, raleigh, started a research project called the Future Renewable Electric Energy Delivery and
Management (FREEDM) System: The Energy Internet. the
research priority of this project is building up a network of
distributed energy resources (ders) that intelligently manages power using secure communications and advanced
power electronics. In the same year, the german Federal
Ministry of economics, technology, and environment
launched the e-energy project, proposing to build up an
Internet of energy, in which information and communication technologies would play a key role to help generate
optimal energy efficiency from ders through intelligent
coordination from generation to consumption.
Since 2012, china also conducted a series of discussions
and preliminary studies on the eI. the State grid corporation of china (Sgcc) proposed the vision of a global energy
Interconnection, which aims to connect electric power systems (ePSs) between different countries and even continents by constructing ultrahigh-voltage (UhV) ac and dc
power transmission lines in the distant future.
In april 2015, tsinghua University established the eI
research Institute (eIrI) to promote eI technologies and
industrial development in china. one of the eIrI's key
advances has been the development of the Integrated energy Management System (IeMS), which serves as the brain
of the eI and will be introduced in detail in this article.

The Concept of the EI
Walls in the Traditional Energy Ecosystem
Walls that hinder openness and efficiency do exist in the
traditional energy system (teS), as shown in Figure 1.
Some of these are tangible. there are walls between multiple energy sectors in the teS, including electricity, heating
and cooling, gas and oil, and transportation, which means
that different teS energy flows are produced, transmitted,
stored, and consumed in different physical systems. For
example, electrical energy is delivered by the power transmission and distribution grid, while gas and oil are usually
brought by pipelines, and heating and cooling power is
usually conveyed by steam and water at a certain temperature in pipes.
additionally, there are some coupling devices, such as
gas turbines, combined heat and power generators, gas
boilers, heat pumps, centralized electric cooling, air

IEEE Elec trific ation Magazine / j u n e 201 8

Table of Contents for the Digital Edition of IEEE Electrification Magazine - June 2018