The Smart Grid, regarded as the next generation power grid, uses two-way flows of electricity and information to create a widely distributed automated energy delivery network. In this article, we survey the literature till 2011 on the enabling technologies for the Smart Grid. We explore three major systems, namely the smart infrastructure system, the smart management system, and the smart protection system. We also propose possible future directions in each system. colorred{Specifically, for the smart infrastructure system, we explore the smart energy subsystem, the smart information subsystem, and the smart communication subsystem.} For the smart management system, we explore various management objectives, such as improving energy efficiency, profiling demand, maximizing utility, reducing cost, and controlling emission. We also explore various management methods to achieve these objectives. For the smart protection system, we explore various failure protection mechanisms which improve the reliability of the Smart Grid, and explore the security and privacy issues in the Smart Grid.

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Smart Grid — The New and Improved Power Grid: A Survey

Smart Grid - The New and Improved Power Grid:

A smart grid is a new form of electricity network with high fidelity power-flow control, self-healing, and energy reliability and energy security using digital communications and control technology. To upgrade an existing power grid into a smart grid, it requires significant dependence on intelligent and secure communication infrastructures. It requires security frameworks for distributed communications, pervasive computing and sensing technologies in smart grid. However, as many of the communication technologies currently recommended to use by a smart grid is vulnerable in cyber security, it could lead to unreliable system operations, causing unnecessary expenditure, even consequential disaster to both utilities and consumers. In this paper, we summarize the cyber security requirements and the possible vulnerabilities in smart grid communications and survey the current solutions on cyber security for smart grid communications.

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A Survey on Cyber Security for Smart Grid Communications

Household smart meters that measure power consumption in real-time at fine granularities are the foundation of a future smart electricity grid. However, the widespread deployment of smart meters has serious privacy implications since they inadvertently leak detailed information about household activities. In this paper, we show that even without a priori knowledge of household activities or prior training, it is possible to extract complex usage patterns from smart meter data using off-the-shelf statistical methods. Our analysis uses two months of data from three homes, which we instrumented to log aggregate household power consumption every second. With the data from our small-scale deployment, we demonstrate the potential for power consumption patterns to reveal a range of information, such as how many people are in the home, sleeping routines, eating routines, etc. We then sketch out the design of a privacy-enhancing smart meter architecture that allows an electric utility to achieve its net metering goals without compromising the privacy of its customers.

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Private memoirs of a smart meter

Optimization of energy consumption in future intelligent energy networks (or Smart Grids) will be based on grid-integrated near-real-time communications between various grid elements in generation, transmission, distribution and loads. This paper discusses some of the challenges and opportunities of communications research in the areas of smart grid and smart metering. In particular, we focus on some of the key communications challenges for realizing interoperable and future-proof smart grid/metering networks, smart grid security and privacy, and how some of the existing networking technologies can be applied to energy management. Finally, we also discuss the coordinated standardization efforts in Europe to harmonize communications standards and protocols.

Smart Grid Communications: Overview of Research Challenges, Solutions, and Standardization Activities

Smart grid privacy encompasses the privacy of information extracted by analysing smart metering data. In this paper, we suggest that home electrical power routing can be used to moderate the home's load signature in order to hide appliance usage information. In particular, 1) we introduce a power management model using a rechargeable battery, 2) we propose a power mixing algorithm, and 3) we evaluate its protection level by proposing three different privacy metrics: an information theoretic (relative entropy), a clustering classification, and a correlation/regression one; these are tested on different metering datasets. This paper sets the ground for further research on the subject of optimising home energy management with regards to hiding load signatures.

Privacy for Smart Meters: Towards Undetectable Appliance Load Signatures

This paper describes the results from a series of long-term observations of spectrum occupancy in the range 300 MHz–4.9 GHz made at a single location. Over 6 months of data has been gathered from a measurement system that is designed to operate continuously, allowing a full picture of spectrum occupancy to be built up. The large amount of data captured permits analysis to identify the portions of spectrum that are occupied non-continuously (i.e. with a duty cycle of less than 100%); these channels might be most suitable for use by a cognitive radio (CR) system that is able to identify temporary spectrum holes and then exploit them. The aim of performing a comprehensive analysis of channel occupancy and its variability is to improve the potential for smart spectrum access by CR devices, by informing their choices concerning the particular portions of spectrum to scan, and how frequently. Results allow measurement channels to be categorised according to their duty cycle; spectrum with a duty cycle between 10% and 90% is considered to be particularly suitable and is found in the regions below 500 MHz and between 1 GHz and 1.2 GHz. A predictable pattern of time occupancy is discovered, caused by variable activity in the portions of spectrum allocated to cellular systems. The characteristics of the occupancy duty cycle according to the time of day is also investigated; some frequencies are shown to exhibit considerable variation of occupancy depending on the hour of observation. A subset of channels is selected for more detailed investigation including short-term variations in channel occupancy.

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Long-term measurements of spectrum occupancy characteristics

The data collected by a home smart meter can potentially reveal sensitive private information about the home resident(s). In this paper, we study how home energy resources can be used to protect the privacy of the collected data. In particular we: a) introduce a power mixing algorithm to selectively protect a set of consumption events; b) develop a range of different privacy protection metrics; c) analyze real smart metering data sampled twice a minute over a period of 13 days; and d) evaluate the protection offered by different power mixing algorithms. Major factors which determine the efficiency of the proposed power mixing algorithms are identified, such as battery capacity and power, and user preferences for privacy-based allocations of battery energy quotas.

ElecPrivacy: Evaluating the Privacy Protection of Electricity Management Algorithms

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2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySpan). Aachen, Germany

The electromagnetic coupling of antennas with the human body is a well-known, but often neglected, problem in body area network (BAN) communications. The resulting distortion of the antenna's free-space characteristics may, in turn, demand more complex terminals to cope with the different conditions encountered as antennas are mounted on different parts of the body and/or varying separations from the skin. Therefore, in this paper, we propose a mounting method to provide a more stable response and to reduce the antenna's coupling to the body for ultra-wideband (UWB) BAN applications. The proposed mounting method is evaluated on two UWB BAN antennas, characterizing the antennas coupling with the body by analyzing variations in the antennas reflection coefficient between 4-9 GHz, when mounted at different distances from the skin and at different locations on the body. The modified mounting method was found to increase the correlation coefficient between the antenna's reflection coefficient when in free space and mounted using 5 mm of spacer, for the two antennas, from 0.22 and 0.13, to 0.66 and 0.90. The free-space characteristics of the modified antennas are also tested, showing a reduction of up to 4.7 dB of radiated power into the body.

Rafael Cepeda

Papers

Privacy for Smart Meters: Towards Undetectable Appliance Load Signatures

Long-term measurements of spectrum occupancy characteristics

ElecPrivacy: Evaluating the Privacy Protection of Electricity Management Algorithms

2011 IEEE International Symposium on Dynamic Spectrum Access Networks (DySpan). Aachen, Germany

An Improved Antenna Mounting for Ultra-Wideband On-Body Communications and Channel Characterization