“Developing an educated workforce ready to build tomorrow’s smart grid creates a strong foundation for the growth of solar energy development in Texas. It benefits local economies, increases jobs, helps preserve air quality and provides affordable energy for generations to come.” -Michael Kuhn, CEO of ImagineSolar
The smart grid is a big idea designed to transform the way Americans generate, distribute and consume power. This new grid will modernize our nation’s electrical system, instituting a broad range of system-wide improvements that will make our electric grid smarter, more efficient, more reliable, safer and meet future demand growth.
The concept is so huge it will take decades to turn into reality, but the work has already begun. To create a sustainable U.S. electric grid, many people need to be involved.
The smart grid offers new market opportunities for professionals in electric power and renewable energy, including electricians, engineers, IT professionals, smart consumer electronics/appliance developers, electric vehicle designers, and others.
SG101
Smart Grid and Distributed Generation
An 8 hour introduction to Smart Grid concepts and technologies
in the electric power industry, describing the challenges facing
today’s electric grid and how the Smart Grid addresses them.
What is a Smart Grid?
The following goals characterize a Smart Grid:
- Increased use of digital information and controls technology to improve reliability, security, and efficiency of the electric grid.
- Dynamic optimization of grid operations and resources, with full cyber-security.
- Deployment and integration of distributed resources and generation, including renewable resources.
- Development and incorporation of demand response, demand-side resources, and energy-efficiency resources.
- Deployment of “smart” technologies (real-time, automated, interactive technologies that optimize the physical operation of appliances and consumer devices) for metering, communications concerning grid operations and status, and distribution automation.
- Integration of “smart” appliances and consumer devices.
- Deployment and integration of advanced electricity storage and peak-shaving technologies, including plug-in electric and hybrid electric vehicles, and thermal-storage air conditioning.
- Provision to consumers of timely information and control options.
- Development of standards for communication and interoperability of appliances and equipment connected to the electric grid, including the infrastructure serving the grid.
- Identification and lowering of unreasonable or unnecessary barriers to adoption of smart grid technologies, practices, and services.
The smart grid implies a fundamental re-engineering of the electricity services industry, but focuses on the technical infrastructure.
Smart Grid’s History
Today’s alternating current (a/c) power grid developed after 1896, based in part on Nikola Tesla’s design published in 1888 (see War of Currents). Much of today’s power grid design was based on the limited technology available 120 years ago.
Specific power grid functions that are now obsolete include centralized unidirectional electric power transmission, electricity distribution, and demand-driven control and represent what the 19th century visionaries thought was possible. Utilities are risk averse when it comes to using untested technologies in critical infrastructure they are in charge of maintaining.
Twentieth century power grids were built as local grids which, over time, became intertied for economic and reliability purposes. One of the largest engineered systems ever constructed–the mature, interconnected electric grid of the late 1960s–became conceived of as “dividing and distributing” electric power on a bulk basis from a small number (i.e. thousands) of “central plant” generating stations, to major load centers, and from there to a large number of individual consumers, large and small.
Generating technologies available for the first three-quarters of the 1900s lent themselves to efficiencies of scale (individual plants of 1000-3000 MW were not uncommon) and to situationally-specific locations (hydroelectric plants at high dams, coal-, gas-, and oil-fired plants near supply lines, nuclear plants near supplies of cooling water, and all of them as far away from population centers as economically possible). As the electric power industry continued to produce more-affordable electricity to a growing base of customers, by the late 1960s it reached nearly every home and business in the developed world.
However, the data-collecting and processing capabilities of the era required broadly averaged, statistical rate classifications that severely limited the timely propagation of supply and demand price signals through the system. Simultaneously, increasing environmental concerns and sociopolitical dependence on electrification combined to limit further economies of scale. By the end of the 20th century, the cost escalation of electric power in major metropolitan areas was considered untenable, and technologies that would remain recognizable to the founders of the industry from a century earlier were no longer considered adequate to an information- and service-based economy.
Over the past 50 years, electricity networks have not kept pace with modern challenges such as:
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- Security threats from energy suppliers and cyber attacks
- National goals to use alternative power sources whose intermittent supply makes maintaining stable power more complex
- Conservation goals that aim to lessen daytime demand surges so we waste less energy and ensure adequate reserves
- High demand for a supply of electricity supply that is uninterruptible
- Digital devices that alter the nature of the electrical load (giving the electric company the ability to turn off appliances in your home if they see fit) and that result in electricity demand that is incompatible with a power system that was built to serve an “analog economy”. For example, timed Christmas lights can present significant demand surges because most of them come on near the same time (sundown). Without the kind of coordination that a smart grid can provide, the increased use of such devices lead to problems with electric service reliability, power quality disturbances, blackouts, and brownouts.
Although these points tend to be the “conventional wisdom” with respect to smart grids, their relative importance is debatable. For instance, despite the weaknesses of power network being publicly broadcast, there has never been an attack on a power network in the U.S. or Europe. However, in April 2009 we learned that spies had infiltrated the power grids, perhaps intending to attack the grid at a later time. In the case of renewable power and its variability, recent work in Europe suggests that a given power network can take up to 30% renewables (such as wind and solar) without any changes whatsoever.
Meanwhile advances in automation, data communications, and distributed generation began to appear adequate to support the concept of a smart grid, which could accommodate suppliers and consumers from a wide range of circumstances, with a greater capacity to anticipate and respond to changing operating conditions and with greater economic efficiency.
The term smart grid has been in use since at least 2005, when the article “Toward A Smart Grid” by S. Massoud Amin and Bruce F. Wollenberg appeared in the September/October issue of IEEE P&E Magazine (Vol. 3, No.5, pgs 34–41). The term may date as far back as 1998.
There are a great many smart grid definitions, some functional, some technological, and some benefits-oriented. A common element to most definitions is the application of digital processing and communications to the power grid, making data flow and information management central to the smart grid. Various capabilities result from the deeply integrated use of digital technology with power grids, and integration of the new grid information flows into utility processes and systems is one of the key issues in the design of smart grids.
Electric utilities now find themselves making three classes of transformations: improvement of infrastructure (called the strong grid in China); addition of the digital layer, which is the essence of the smart grid; and business process transformation, necessary to capitalize on the investments in smart technology. Much of the modernization work that has been going on in electric grid modernization, especially substation and distribution automation, is now included in the general concept of the smart grid, but additional capabilities are evolving as well.
Smart grid technologies have emerged from earlier attempts at using electronic control, metering, and monitoring. In the 1980s, Automatic meter reading was used for monitoring loads from large customers, and evolved into the Advanced Metering Infrastructure of the 1990s, whose meters could store how electricity was used at different times of the day. Smart meters add continuous communications so that monitoring can be done in real time and can be used as a gateway to demand response aware devices and “smart sockets” in the home. Early forms of such demand side management technologies were dynamic demand aware devices that passively sensed the load on the grid by monitoring changes in the power supply frequency. Devices such as industrial and domestic air conditioners, refrigerators and heaters adjusted their duty cycle to avoid activation during times the grid was suffering a peak condition.
Beginning in 2000, Italy’s Telegestore Project was the first to network large numbers (27 million) of homes using such smart meters connected via low bandwidth power line communication. Recent projects use Broadband over Power Line (BPL) communications, or wireless technologies such as mesh networking that is advocated as providing more reliable connections to disparate devices in the home as well as supporting metering of other utilities such as gas and water.
In the early 1990s, monitoring and synchronizing large networks were revolutionized when the Bonneville Power Administration expanded its smart grid research with prototype sensors that are capable of very rapid analysis of anomalies in electric quality over very large geographic areas. The culmination of this work was the first operational Wide Area Measurement System (WAMS) in 2000. Other countries are rapidly integrating this technology. China will have a comprehensive national WAMS system when its current 5-year economic plan is complete in 2012.
Source: Wikipedia
