Sedat Gormus

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

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.

A mesh-radio-based solution for smart metering networks

Propelled by the need to reduce the impact on the environment and improve energy efficiency, we see an impetus toward enabling a smart grid. One of the key constituents of the smart grid is the automated metering infrastructure, which is expected to facilitate the transport of meter readings from meters to the utility provider, and (potentially) control information in the other direction. A range of communication technologies are being considered for realizing AMI networks with no clear winner so far. This article provides an overview of some of the candidate solutions and proposes a mesh-radio based solution. The proposed solution is an enhanced version of the RPL protocol and exhibits self-organizing characteristics, and is practical and therefore attractive from a deployment perspective. Additionally, we also discuss network operational issues to improve robustness and scalability, as well as fault recovery due to link failure.

A self-organising mesh networking solution based on enhanced RPL for smart metering communications

Motivated by the need to improve energy efficiency and reduce the impact on the environment, we see efforts directed towards enabling a ‘Smart Grid’. One of the key elements of the Smart Grid is the Automated Metering Infrastructure (AMI) which is expected to facilitate the transport of meter readings from meters to the utility provider and control information (potentially) in the other direction. Different solution strategies for realizing AMI networks are currently being debated in the community with no clear consensus so far. This paper proposes a mesh radio based solution which exhibits self-organizing characteristics and is therefore attractive from a deployment perspective. The proposed solution has been realized as enhancements to the RPL protocol, a connectivity enabling mechanism for low power and lossy networks currently being standardized by the IETF ROLL working group. It enables smart meter nodes augmented with the mesh radio to automatically discover concentrator nodes in the vicinity, setup a single/multi-hop link to the best available concentrator, detect loss of connectivity and subsequently re-configure itself to re-establish connectivity so as to ensure reliable transport of smart metering data. Moreover, it achieves this in a distributed manner thereby ensuring scalability. Results from the evaluation of the proposed solution through emulation based experiments further confirm this.

AMI Mesh Networks—A Practical Solution and Its Performance Evaluation

Automated metering is expected to be an integral part of the modern energy grid. Automated metering entails transport of metering data from the energy consumers premises to the data management systems of the energy provider and potentially information in the other direction. This paper describes a practical mesh networking solution based on extensions proposed to the routing protocol for low power and lossy networks (RPL) to realize automated metering communications. This solution comprises self-organizing algorithms to enable smart meters to automatically discover connectivity and recover from loss of connectivity. Results from a theoretical analysis, simulation based experiments and measurements carried out from a network deployed in our office premises are presented to show the efficacy of the proposed solution. In particular, we study the impact of these algorithms on the network discovery latency, recovery latency, and packet delivery ratio. Findings from this study demonstrate that this solution can improve scalability and performance of the network. Moreover, this solution is practical from an implementation perspective.

The POWER of Networking: How Networking Can Help Power Management

There is a growing concern worldwide to reduce the carbon footprint through reducing reliance on fossil fuel based energy sources and improving energy efficiency. Fueled by this, the quest to enable a Smart Grid, which aims to reduce reliance on fossil fuels, match the demand to the available supply and improve energy efficiency is gaining momentum. One of the key components of the Smart Grid will be to level the load, i.e. the ability to shift the demand in time so as to match the available supply and in so doing improve utilisation of resources and reduce (ideally avoid) the reliance on environment unfriendly reserve sources of energy as much as possible. This paper discusses the challenges in achieving such load levelling and elaborates on how existing techniques from networking research could be potentially applied to solve these problems. The broader objective of this paper is to initiate discussion and encourage research in the areas highlighted.

Residential energy demand management in smart grids

This paper studies a coordination mechanism based on heuristic rules to manage the energy demand in a residential smart grid scenario and evaluates the survivability of the system when failures occur in the communication infrastructure. This is achieved by modeling residential demand response considering Plug-in Hybrid Electric Vehicles (PHEVs) as part of the loads, local renewable generation capability and variable energy pricing based on a Time of Use (TOU) scheme. A mathematical model of the system is built based on realistic data, and the evaluation of the survivability of the system is carried out using Monte Carlo simulations and statistical experiment design techniques, where the probability of overloading the distribution system is derived for different scenarios. Results obtained show that the coordination mechanism is able to achieve energy efficiency and cost saving for residential users when the energy consumption is managed properly. At the same time the probability of overloading the distribution system can be reduced. The efficiency and economic savings depend on the potential of renewable sources in the region considered and the survivability of the system depends on a reliable communication infrastructure.

Energy efficient body area networking for mHealth applications

Propelled by the need to reduce the cost of caring for the ageing population, we observe an impetus towards enabling remote patient monitoring (mHealth) via low power medical sensor networks. A practical mHealth network consisting of several sensor modules located on the patients body needs to operate over long periods of time without any intervention. This requires efficient hardware and software design which will enable the battery powered sensor devices to operate efficiently and reliably with minimal energy consumption. This paper combines efficient antenna design with a cross layer energy efficient protocol to realize wireless body area networks (WBANs) where the main aim is to maximise network life time. Towards this goal, we demonstrate a high efficiency system design approach where the performance of WBANs are greatly enhanced.

Opportunistic RPL for reliable AMI mesh networks

Driven by the need to improve energy efficiency and reduce environmental impact, we observe a thrust towards enabling a Smart Grid. It is envisaged that to achieve these goals, the Smart Grid will be equipped with communications infrastructure and mechanisms that will enable near real-time control of the grid components. One of the key elements of the Smart Grid is the advanced metering infrastructure (AMI) which is expected to facilitate the transport of meter readings from a smart electricity meter at the customer premises to the utility provider, and control data in the other direction. These communications can be potentially realized by deploying a self-organizing mesh network composed of smart metering nodes connected to concentrator nodes which in turn are connected to the utility provider data management systems. This paper explores a cooperative communications approach to improve reliability of such mesh networks. The proposed opportunistic forwarding protocol called ‘ORPL’ has been realized as an enhancement on top of the routing protocol for low power and lossy networks, a connectivity enabling mechanism in AMI mesh networks. In ORPL, smart meter nodes select multiple candidate relays to facilitate reliable transport of smart metering data to the concentrator node. Moreover, it is designed to work in a distributed manner thereby ensuring scalability. We also present a further extension to ORPL, i.e., ORPLx with adaptive medium access control retransmit limit, which reduces unnecessary retransmissions. Our protocols have been evaluated and verified with comprehensive experimental results, demonstrating their effectiveness and favorable characteristics.

A Comparison of Centralized and Distributed Monitoring Architectures in the Smart Grid

Wireless sensor networks (WSNs) are attracting attention in the context of smart grids as they can facilitate the development of future energy consumption monitoring systems. In this paper, we present a comparison of the performance of four WSN architectures for energy consumption monitoring. The aim of this work is to explore the benefits of having distributed storage and processing compared with centralized approaches. Performance of the architectures was evaluated, considering energy consumption, processing, storage and bandwidth requirements, as well as capital costs involved. Results show that architectures requiring distributed processing and storage significantly improve the energy efficiency; nonetheless, deploying these architectures requires a relatively higher investment in comparison to centralized approaches.

WISEMEN: White Space for Smart Metering

In this paper we present a case for Smart Metering to be a prime application of TV White Spaces (TVWS) and investigate network architecture to enable smart metering communication in TVWS that ensures access reliability, primary user protection (if one exists) and efficient use of spectrum. We consider the communication access network connecting the smart meters to the concentrator as a wireless mesh network and propose using Radio Environment Maps (REMs) in conjunction with a geo-location database to manage the channel being used by the concentrator for communicating with the smart metering nodes. We also examine through emulation based experiments, the effect of primary user arrival interval on the packet delivery ratio of the smart meter nodes and the time it takes for the network to migrate to a vacant channel subsequent to detecting primary activity on the operating channel. Our findings suggest that it is feasible to realise smart metering communications in the TVWS and that the proposed mechanism shows good adaptive behaviour.