Fast Facts on Smart Electricity Grids
1 What is Smart Grid
There are various definitions, but broadly, they all refer the use of enhanced power equipment/technologies, monitoring devices (sensors) and communication systems to make the electricity grid observable (able to measure the states of critical grid elements), controllable (able to affect the state of any critical grid element), automated (able to adapt and self-heal from network incidents), user-friendly (two way utility-customer interaction) and environmentally friendly.
A smart grid combines the power of information technology and automation. It would enable two-way communication between consumers and power companies such that home thermostats and appliances would automatically adjust to take advantage of low-cost power periods. The smart grid conceptual model is shown in Fig. 1
Fig. 1: Smart Grid Conceptual Model
2 Smart Grid Characteristics
Based on the Electric Power Research Institute’s (EPRI) definition, a smart grid should comprise the following characteristics:
2.1 Enable Active Participation by Consumers
The smart grid consumer is informed, modifying the way they use and purchase electricity. They have choices, incentives, and disincentives which modifies their purchasing behaviour.
2.2 Accommodate All Generation and Energy Storage Options
The Smart Grid accommodates all generation and storage options. It supports large, centralized power plants as well as Distributed Energy Resources (DER), eg. solar panels, wind farms. As energy storage technologies mature, they will be an integral part of the overall Smart Grid solution set.
2.3 Enable New Products, Services, and Markets
The Smart Grid enables regulators, aggregators and operators, and consumers to modify the rules of business to create profit or cost reduction opportunities for market participants. Innovative products and services provide third party vendors opportunities to create market penetration opportunities and consumers with choices and clever tools for managing their electricity costs and usage.
Fig. 2: Opportunities for New Products, Services, and Markets
2.4 Provide Power Quality for the Digital Economy
The Smart Grid provides reliable power that is relatively “clean” and interruption-free so that digital devices that power the productivity of our 21st century economy can run continuously.
2.5 Optimize Asset Utilization and Operate Efficiently.
The Smart Grid optimizes assets and operates efficiently so as to reduce cost. Routine maintenance and self-health regulating abilities allow assets to operate longer with less human interaction.
2.6 Anticipate and Respond to System Disturbances (Self-heal)
The Smart Grid independently identifies and reacts to system disturbances and performs mitigation efforts to correct them. It incorporates an engineering design that enables problems to be isolated, analyzed, and restored with little or no human interaction. It performs continuous predictive analysis to detect existing and future problems and initiate corrective actions. It will react quickly to electricity losses and optimize restoration exercises.
2.7 Operate Resiliently to Attack and Natural Disaster
The Smart Grid resists attacks on both the physical infrastructure (substations, poles, transformers, etc.) and the cyber-structure (markets, systems, software, communications). Sensors, cameras, automated switches, and intelligence are built into the infrastructure to observe, react, and alert when threats are recognized within the system. The system is resilient and incorporates self-healing technologies to resist and react to natural disasters. Constant monitoring and self-testing are conducted against the system to mitigate malware and hackers.
3 Smart Grid Benefits
Smart grids are designed to bring about benefits for the major stakeholders comprising of consumers, utilities, and the society at large in the following ways:
• Power reliability and power quality. The Smart Grid provides a reliable power supply with fewer and briefer outages, “cleaner” power, and self-healing power systems, through the use of digital information, automated control, and autonomous systems.
• Safety and cyber security benefits. The Smart Grid continuously monitors itself to detect unsafe or insecure situations that could detract from its high reliability and safe operation. Higher cyber security is built in to all systems and operations including physical plant monitoring, cyber security, and privacy protection of all users and customers.
• Energy efficiency benefits. The Smart Grid is more efficient, providing reduced total energy use, reduced peak demand, reduced energy losses, and the ability to induce end-user use reduction instead of new generation in power system operations.
• Environmental and conservation benefits. The Smart Grid is “green”. It helps reduce greenhouse gases (GHG) and other pollutants by reducing generation from inefficient energy sources, supports renewable energy sources, and enables the replacement of gasoline-powered vehicles with plug-in electric vehicles.
• Direct financial benefits. The Smart Grid offers direct economic benefits as operations costs are reduced or avoided. Customers have pricing choices and access to energy information. Entrepreneurs accelerate technology introduction into the generation, distribution, storage, and coordination of energy.
4 Smart Grid Challenges
The migration from the conventional grid (one-way power flow from generators to end-consumers) towards the smart grid which enables two-way power flows and communication poses tremendous challenges, both administratively and technically. The areas of challenges are:
• Transition to Smart Grid. The transition to the Smart Grid will be lengthy. It is impossible (and unwise) to advocate that all the existing equipment and systems to be ripped out and replaced at once. The smart grid supports gradual transition and long coexistence of diverse technologies. We must design to avoid unnecessary expenses and unwarranted decreases in reliability, safety, or cyber security.
• Development of and Consensus on Standards. It is necessary to tap the expertise and insights of a broad group of stakeholders. The work is challenging and time consuming but yields stronger standards.
• Development of robust Smart Equipment. Smart equipment refers to all field equipment which is computer-based or microprocessor-based, including controllers, remote terminal units (RTUs), intelligent electronic devices (IEDs). It includes the actual power equipment, such as switches, capacitor banks, or breakers. It also refers to the equipment inside homes, buildings and industrial facilities. This embedded computing equipment must be robust to handle future applications for many years without being replaced.
• Communication systems. Communication systems refer to the media and to the developing communication protocols. These technologies are in various stages of maturity. The smart grid must be robust enough to accommodate new media as they emerge from the communications industries and while preserving interoperable, secured systems.• Data management. Data management refers to all aspects of collecting, analyzing, storing, and providing data to users and applications, including the issues of data identification, validation, accuracy, updating, time-tagging, consistency across databases, etc. Data management methods which work well for small amounts of data often fail or become too burdensome for large amounts of data—and distribution automation and customer information generate lots of data. Data management is among the most time-consuming and difficult task in many of the functions and must be addressed in a way that will scale to immense size.
5 Smart Grid Developments –Global Scan
The economic stimulus package announced by that President Barack Obama in Feb 09 includes a US$4.5 billion down payment on building smart grids. Calling the development of a smart electric power grid an "urgent national priority," the Obama administration further unveiled a set of 16 standards in May 09 to help ensure that new devices can send vital information to power suppliers. The new standards encompass areas including smart customer meters, distributed power generation components and cyber-security. Although the smart grid will be many years in the making, the development of standards is an important first step to guide the private sector in manufacturing products for smart grid use.
Over in Australia, the government said it would dedicate up to A$100 million (US$79 million) in the development of smart grid technology in 2009.
China, according to the Renewable Energy World, has plans to build a smart grid by 2020.
