Wikipedia provide a good definition: http://en.wikipedia.org/wiki/Smart_grid

you can start from this one

A smart grid is power system where the operation, measurement and control of entire power system( from generation to transmission to distribution to utilization) is through use of latest ICT( information and communication technology)

A smart grid is a modernized electrical grid that uses information and communications technology to gather and act on information, such as information about the behaviors of suppliers and consumers,

A smart grid is an evolved grid system that manages electricity demand in a sustainable, reliable and economic manner, built on advanced infrastructure and tuned to facilitate the integration of all involved.

A Smart grid is an idea which includes the conception of bidirectional flow of data (information) as well as the power also. This would lead to the higher flexibility of the whole grid to be monitored controlled and protected. This system allows for monitoring, analysis, control and communication within the supply chain to help improve efficiency, reduce the energy consumption and cost, and maximize the transparency and reliability of the energy supply chain. Smart net meters are new technology that is to be included unlike the conventional grid.

A Smart Grid is a Bidirectional Decentralized Power System Concept.

I think this is the most official document (applicable for Europe) that one can find.

Take note that in the US, the smart grid concept is more or less

limited to microgrids, while in Europe (conceptually) it encompasses from microgrids (ie Distribution systems) to super-grids (intra-national Transmission systems).

There are differences even for Distribution systems. In the US the concept, I think, does not permit bi-directional power flows (from the Distribution System to higher Voltage Levels), while in Europe it does so. http://ec.europa.eu/energy/gas_electricity/smartgrids/doc/xpert_group1_reference_architecture.pdf

'Smart grid’ has no globally agreed definition. It covers a wide range of innovations and technologies in the energy sector, impacting electricity generation, transmission, distribution and consumption.

The Electricity Networks Strategy Group (ENSG) defines the smart grid as:

"part of an electricity power system which can intelligently integrate the actions of all users connected to it - generators, consumers and those that do both - in order to efficiently deliver sustainable, economic and secure electricity supplies".

Smart grid can be defined as auto control of electrical power system by using advanced information and communication technology , which is capable of measuring, controlling, monitoring and delivering energy by integrating the supply and demand of energy.

Dr. K.K.Puranik

Director RKDF Institute of Science & Technology Bhopal India

May I suggest a possible everyday kind of suggestion motivated only

by the adjective "smart".

The following problems are I think faced by a typical power network.

1. Economic Load despatch which basically says from which

generating station a cost effective energy supply can take place.

2. Protection and recovery during fault

3. Planned Load shedding (maintaining continuity for critical loads.

4. Metering and advise to consumers to operate on low tariff

5.SCADA

Most problems earlier have been addressed without the

availability of instantaneous data at the operating side( although there was

some use of Powerline carrier systems).

Now with fast Communications and Information Technology it is possible

to solve the above problems in an improved manner.

So my simple and concise definition of Smart Grid

is a grid which incorporates intelligence to meet variable

demand of electrical energy to all consumers in an effective , economical

and acceptable way.

There are several "official" definitions of Smart Grids out there. The IMHO most prominent ones are:

(1) taken from NIST Framework and Roadmap, Security Act of 2007:

The term “Smart Grid” refers to a modernization of the electricity delivery system so it monitors, protects and automatically optimizes the operation of its interconnected elements – from the central and distributed generator through the high-voltage transmission network and the distribution system, to industrial users and building automation systems, to energy storage installations and to end-use consumers and their thermostats, electric vehicles, appliances and other household devices.

The Smart Grid will be characterized by a two-way flow of electricity and information to create an automated, widely distributed energy delivery network. It incorporates into the grid the benefits of distributed computing and communications to deliver real-time information and enable the near-instantaneous balance of supply and demand at the device level.

(2) from EU's TP on Smart Grids:

A SmartGrid is an electricity network that can intelligently integrate the actions of all users connected to it – generators, consumers and those that do both – in order to efficiently deliver sustainable, economic and secure electricity supplies. A SmartGrid employs innovative products and services together with intelligent monitoring, control, communication, and self-healing technologies to:

**better facilitate the connection and operation of generators of all sizes and technologies;

**allow consumers to play a part in optimizing the operation of the system;

**provide consumers with greater information and choice of supply;

**significantly reduce the environmental impact of the whole electricity supply system;

**deliver enhanced levels of reliability and security of supply.

SmartGrids deployment must include not only technology, market and commercial considerations, environmental impact, regulatory framework, standardization usage, ICT (Information & Communication Technology) and migration strategy but also societal requirements and governmental edicts.

In addition to my prior answer I'd like to define the "smart" in Smart Grids as trying to find the most efficient (in terms of communication, reserve capacities... or more general costs) way of operating the electrical energy system under the currently changing conditions.

I think that there is no exact definition of smart grid because in many papers, the researchers called it conform to her/his purposes. But, I think that the main of smart grid is the electric system which is can be control itself.

"Smart grid can be defined as closed loop control and monitoring of power system and utilization using latest information and communication technology"

Dear

Since there is no unique definition for Smart Grid yet, I recommend you study the paper titled "What is the Smart Grid? Definitions, Perspectives, and Ultimate Goals" which is available in my RG-page at

https://www.researchgate.net/publication/259981754_What_is_the_Smart_Grid_Definitions_Perspectives_and_Ultimate_Goals

Regards,

Morteza Shabanzadeh

http://mortezash.blogfa.com/

Conference Paper What is the Smart Grid? Definitions, Perspectives, and Ultimate Goals