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Smart Grid (From Wiki)

Smart grid

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A smart grid delivers electricity from suppliers to consumers using digital technology to control appliances at consumer's homes to save energy, reduce cost and increase reliability and transparency. Such a modernized electricity network is being promoted by many governments as a way of addressing energy independence, global warming and emergency resilience issues.

The idea behind the "smart grid" is to have devices that plug into your outlet and you would plug your appliance into this device. These devices would communicate and report to the electric companies at what time your appliance used energy and how much and use that to charge you more for electricity that you use during peak hours of late afternoon and early evening (175% increase in some countries in europe) and the electric company would offset that increase in price by giving up to 90% discounts during the low demand hours (generally between midnight and 5am). This would result in generous increases in electric bills, thus "forcing" consumers to try and save energy by using as little as possible during peak hours. Through some method not devised yet, you would let the electric company know what you have plugged into each of your devices, and in order to avoid a blackout or brownout they could selectively turn devices off in your home. This broad power given to the electric companies raises the question of privacy since technically, the electric company would be able to know when and for how long you used each the appliances in your home. No information has come forth as of yet on whether the electric companies would sell this information.

As with any heavily promoted initiative, many similar proposals have many similar names, including at least smart electric grid, smart power grid, intelligent grid (or intelligrid), FutureGrid, and the more modern intergrid and intragrid.

Deployments and deployment attempts

One of the first attempted deployments of "smart grid" technologies in the United States caused a firestorm of criticism and was recently rejected by electricity regulators in the Commonwealth of Massachusetts, a US state.[1] According to an article in the Boston Globe, Northwest Utilities' Western Massachusetts Electric Co. subsidiary actually created a "smart grid" program using public subsidies that would switch low income customers from post-pay to pre-pay billing (using "smart cards") in addition to special hiked "premium" rates for electricity used above a predetermined amount.[1] This plan was rejected by regulators as it "eroded important protections for low-income customers against shutoffs".[1] According to the Boston Globe, the plan "unfairly targeted low-income customers and circumvented Massachusetts laws meant to help struggling consumers keep the lights on".[1] A spokesman for an environmental group supportive of smart grid plans and Western Massachusetts' Electric's aforementioned "smart grid" plan, in particular, stated "If used properly, smart grid technology has a lot of potential for reducing peak demand, which would allow us to shut down some of the newest, dirtiest power plants... It’s cool."[1]

Goals

In principle, the smart grid is a simple upgrade of 20th century power grids which generally "broadcast" power from a few central power generators to a large number of users, to instead be capable of routing power in more optimal ways to respond to a very wide range of conditions, and to charge a premium for those that use energy at peak hours (5-8pm). >This could mean a 15 minute shower would cost you $0.93 in the morning or late at night, but cost you $2 if you decide to shower between 5-8pm. Similarly, 30minutes of your oven being turned would cost about $13 during the day or late at night, this would become $26+ dollars if you decide to cook dinner between 5-8pm.

Respond to many conditions in supply and demand

The conditions to which a smart grid, broadly stated, could respond, occur anywhere in the power generation, distribution and demand chain. Events may occur generally in the environment (clouds blocking the sun and reducing the amount of solar power, a very hot day), commercially in the power supply market (prices to meet a high peak demand exceeding one dollar per kilowatt-hour), locally on the distribution grid (MV transformer failure requiring a temporary shutdown of one distribution line) or in the home (someone leaving for work, putting various devices into hibernation, data ceasing to flow to an IPTV), which motivate a change to power flow.

Latency of the data flow is a major concern, with some early smart meter architectures allowing actually as long as 24 hours delay in receiving the data, preventing any possible reaction by either supplying or demanding devices.[2]

Provision megabits, control power with kilobits, sell the rest

The amount of data required to perform monitoring and switching your appliances off without your consent is very small compared with that already reaching even remote homes to support voice, security, Internet and TV services. Many smart grid bandwidth upgrades are paid for by over-provisioning to support also consumer services, and subsidizing the communications with energy-related services or subsidizing the energy-related services, such as higher rates during peak hours, with communications. This is particularly true where governments run both sets of services as a public monopoly, e.g. in India. Because power and communications companies are generally separate commercial enterprises in North America and Europe, it has required considerable government and large-vendor effort to encourage various enterprises to cooperate. Some, like Cisco, see opportunity in providing devices to consumers very similar to those they have long been providing to industry.[3] Others , such as Silver Spring Networks[4] or Google [5][6], are data integrators rather than vendors of equipment. While the AC power control standards suggest powerline networking would be the primary means of communication among smart grid and home devices, the bits may not reach the home via BPL initially but by fixed wireless. This may be only an interim solution however as separate power and data connections simply defeats full control.

Scale and scope

Europe's SuperSmart Grid, as well as earlier proposals (such as Al Gore's continental Unified Smart Grid) make semantic distinctions between local and national grids that sometimes conflict. Papers [7] by Battaglini et al. associate the term "smart grid" with local clusters (page 6), whereas the intelligent interconnecting backbone provides an additional layer of coordination above the local smart grids. Media use in both Europe and the US however tends to conflict national and local.

Regardless of terminology used, smart grid projects always intend to allow the continental and national interconnection backbones fail without causing local smart grids to fail. They would have to be able to function independently and ration whatever power is available to critical needs.

Municipal grid

Before recent standards efforts, municipal governments, for example in Miami, Florida[8], have historically taken the lead in enforcing integration standards for smart grids/meters. As municipalities or municipal electricity monopolies also often own some fiber optic backbones and control transit exchanges at which communication service providers meet, they are often well positioned to force good integration.

Municipalities also have primary responsibility for emergency response and resilience, and would in most cases have the legal mandate to ration or provision power, say to ensure that hospitals and fire response and shelters have priority and receive whatever power is still available in a general outage.

Home grid

A "home grid" extends some of these capabilities into the home using powerline networking and extensions to DC (power over Ethernet). The IEEE P2030-specified interoperability standards are expected to resolve these distinctions and clarify global, continental, regional, municipal and home scopes. The distinctions are similar to those that are required to differentiate types of LAN, Internet Protocol and the Internet itself. Since many of the same technologies are used in smart and home grids, notably IPv6 and SNMP, terminology such as intergrid and intragrid is sometimes used in the trade press.

Because of the communication standards both smart power grids and home grids build on support more bandwidth than is required for power control, a home grid generally has megabits of additional bandwidth for other services (burglary, fire, medical and environmental sensors and alarms, ULC and CCTV monitoring, access control and keying systems, intercoms and secure phone line services), and accordingly can't be separated from LAN and VoIP networking, nor from TV once the IPTV standards have emerged.

Consumer electronics devices now consume over half the power in a typical US home. Accordingly, the ability to shut down or hibernate devices when they are not receiving data could be a major factor in cutting energy use, but this would mean the electric company has information on whether you are using your computer or not, and if, for example, you simply has a screen saver on with family pictures while you do chores or work around the house, the electric company could at their discretion decide your computer is not being used and turn it off for you.

Government support and developments

In 2009, smart grid companies may represent one of the biggest and fastest growing sectors in the "cleantech" market [9]. It consistently receives more than half the venture capital investment.

In 2009 President Barack Obama asked the United States Congress "to act without delay" to pass legislation that included doubling alternative energy production in the next three years and building a new electricity "smart grid". [10] On April 13, 2009, George W. Arnold was named the first National Coordinator for Smart Grid Interoperability [11]. In June 2009, the NIST announced a smart grid interoperability project via IEEE P2030[12].

Europe and Australia are also following similar visions. In those parts of the world, the integration of communications and power control, both of which have generally fallen under more government supervision, is more advanced, with utilities often required or asked to provide competitive access to communications transit exchanges and distributed power co-generation connection points.


On August 20, 2009, Casa Presedencial in Costa Rica introduced a bill to the country's Legislative Assembly that would open up the energy market, which is currently run by a government monopoly, and require all new private electricity generators to use smart grid technology.

Researchers and regulators support IP, closer power and data ties

Bill St. Arnaud of CANARIE (Canada's backbone research institute) argues often for closer integration of power and telecom policy, proposing that consumers should own their own power meter data explicitly and that they should have a choice of service providers for communication and power management, with reach potentially into every home AC outlet. [13] In the US, FCC Chair Michael Powell likewise expresses support for this principle of unifying the power management and other data services and offering basic levels of both to every consumer, rather than allowing power management to exist in its own separate "silo" or be confined only to non-IP-based meters or devices.

The IEEE P2030 project seeks to define interoperability between various types of power grids, in part to prevent the emergence of too many incompatible silos that would cause the overall grid to be less resilient.

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