An electric meter is an electrotechnical body being used to measure the electric amount of power consumed in a place: dwelling, industry It is used by the providers of electricity in order to invoice power consumption with the customer. In the beginning these apparatuses were of electromechanical design, they are replaced henceforth by electronic models.
The legal unit of energy is the joule, corresponding to a power of one Watt during one second. However, the unit of energy usually used for electricity consumption is the kilowatt-hour (kWh). One kWh is equivalent to 3,6 * 106J.
Various types of meters
Traditional meters electromechanics
They are the oldest meters. One recognizes them with their disc which turns. They are fixed using three points of fastener. Its interest is its great robustness and its facility of installation.
The system of counting is electronic and often less cumbersome than the traditional meters. They can be with mechanical display or LCD (DIGITAL). These meters are more sensitive to the overcurrents and overpressures, and particularly the lightning.
The modular electric meters have an electronic system of measurement. They may find it beneficial to be compact. They are also easy of installation because is assembled on rail DIN. The display can be mechanical or LCD (DIGITAL)
"Modular" meter Single-phase current
Various types of display.
The mechanical display is oldest of the displays. Compared to display LCD, it has the advantage of being able to be read including at the time of power cuts. Moreover, in the event of deterioration or of vandalism, the last recorded value remains displayed, which makes its reading always possible.
Display LCD (DIGITAL)
Display LCD (DIGITAL) has the advantage of being able to display various information: tariffs of kWh, Watt, tension). It is thus often used on the complex meters.
Intelligent electric meter
An intelligent meter is a meter having advanced technologies, known as AMR (Automated Meter Reading) which identifies in a more detailed way and specifies, and possibly in real-time the energy consumption of a hearth, a building or a company, and transmit it, by telephone or powerline communication (CYBERATHLETE PROFESSIONAL LEAGUE), with the manager of the data of counting (in France, mission entrusted to the distributer by the law of December 7th, 2006.
The intelligent meters can in particular establish invoices in real-time and locate the stations which cost the customer more. They can possibly inform it of micro-interruptions or losses on the electrical communication. From the point of view of the company, they allow productivity gains important via the suppression of employment of personnel in charge of the statement of the meters.
When the meter in more programmable and is remotely equipped with an apparatus of remote cut, it is known as AM. This second quality is capital because it goes well beyond the simple remote statement and opens the whole of the distribution network of electricity to major evolutions génériquement known under the name of intelligent network. However, these meters also have important disadvantages for the user in terms of cost and potential attack to the private life in particular.
According to the sources, the terms communicating meters, advanced meters or smart meters are also employed to indicate this new generation of electricity meters.
The progressive deregulation of the markets of electricity and gas in the world, as well as the increasing interconnection of the networks encouraged agencies and government organizations of regulation or regulation to seek means better of knowing, of envisaging and of controlling electricity consumption, gas and of water of the inhabitants, a district, an area or a country.
the promoters of these meters aim at inciting the customers with less consuming, by the establishment of prices differentiated in real-time, at the hours of peaks (surtarification) foreseeable according to the hours of the day and the season. That is supposed to encourage the customers to consume less energy and to allow total savings in energies in a durable developmental perspective. Indeed, by allowing a follow-up of consumption, these systems would make it possible to carry out energy saving from 5 to 15%, by supporting better practices. These meters also make it possible to remotely cut off with the agreement of the customers the supply of certain equipment, to avoid the overloads of the network in peak period.
The intelligent meters also make it possible to carry out certain remote operations, without a technician moving and that the customer is present. By eliminating the manual duties from changing, of change of power, cut or restarting, these meters are judicious in the long term to allow a reduction in the costs of distribution of energy and times of intervention. It was stressed that would involve the disappearance of many uses of this type at ErdF. These meters will make it possible moreover to have an invoice based on a consumption in real-time, rather than on an alternation of statements on site and estimates.
The precision of these meters and the connection constants which they maintain with the provider electricity are considered to be alarming because of possible invasions of privacy which they allow. Thus, the European Office of consumers unions (BEUC) worries about the possible drifts in police and commercial matters: The manager can know, in theory, minute per minute in what a part you are and what made you there! thus raise Levi Nietvelt, adviser in charge of energy with the BEUC.
An data encryption transmitted should nevertheless avoid piracy and the providers to see itself imposing strict rules in the use of this information. In France, the Commission of regulation of energy (CRE) constituted an Working Group on this subject including Cnil (National Commission of data processing and freedoms).
The latter has, on this occasion, warned EDF as for the need for serious guarantees on the data confidentiality, taking into account the fact that in the long term these meters will make it possible to know much of things about the occupants of a dwelling, like their schedule of alarm clock or the moment when they take a shower.
In addition, the cost of these apparatuses is not very negligible: they would cost between 12 and 24 euros per annum during ten years at each user and their cost could even double compared to the price initially envisaged.
In the whole world, governments and distributers of electricity seized the question, encasing the step in Italy, first large country with being completely equipped with this generation of meters.
In September 2009, the European Union laid down at the Member States an objective of deployment of the intelligent meters in 80% of the European hearths from here 2020, and 100% from here 2022. This European directive must be transposed in the national right of each Member State before March 2011.
This directive lies within the scope of the objective of three times 20 proposed by the European commission to fight the climatic change: to increase by 20% the proportion of the renewable sources in mix energetics; to decrease by 20% the gas emissions with greenhouse effect (GES); to improve energy efficiency of 20% from here at 2020. The European commission estimates that a reduction of the energy expenditure of 10% can be reached thanks to the intelligent meters.
Sweden and Italy are the first countries to have undertaken the installation of intelligent meters.
The Linky project
The principal French distributer, ERDF, launched in 2007 the project Linky (name given officially to the meter in March 2009). This project ambitionne the equipment of whole France out of meters AM by 2021, is 35 million customers equipped, at an announced cost of 4 billion euros. Consumers associations expressed concerns concerning the financing of these apparatuses.
The French government will decide this generalization, at the conclusion of the experimental phase at the end of the winter 2011.
According to ERDF, the generalization of the meter Linky would allow:
for the network drivers: a cost cutting of management,
for the providers: a reduction of the frauds and complaints, and a greater wealth of information allowing to propose to the customers new offers,
for the producers: a better control of peak demand and a simplification of the installation of photovoltaic panels,
for the customers: invoices established systematically on their real consumption, of the interventions carried out without intervention inside the residence and appointment management, as well as a more precise follow-up of their electricity consumption.
Since January 1st, 2010, the industrial customers connected in BT can have their own communicating meter, meter "SME". This one is not the subject yet of a massive deployment but it will equip these customers in the event of failure with the old meters or creation of a point of delivery. The industrial customers connected in HTA as for them will be covered by the future meter HTA whose implementation is envisaged in 2013. Linky, SME and HTA will thus form the complete range of the French communicating meters, according to the projects of ERDF.
Ademe led an evaluation of the benefit for the environment of the Linky meter, and has conlu at the end of 2010 that the real profit in energy saving for the consumer was not proven, recommending one year additional of test, and the addition of an additional mechanism of display connected to the meter and located inside housing for better informing the consumer. It one of criticisms was done by the detractors of Linky
Linky single-phase current and three-phase current have same dimensions appreciably as their predecessors, the electronic supply meters (CBE) mono and three-phase. The Linky meter embarks all the existing functionalities on the CBE to which it comes to add those of its generation (measurements on 14 index, statement of load diagram, communication CYBERATHLETE PROFESSIONAL LEAGUE with the concentrators), symbolized by the presence of an USB port in frontage, which however cannot receive a standard USB device but is intended to offir the functionalities (already existing on the CBE) of TV-information customer (TIC)
During the experimentation of 2010, the Linky meters are not connected to the bus of téléreport Euridis, in order to avoid confusion between CBE and Linky at the time of the remote readings. One will note moreover than Linky exploits a more advanced version of Euridis: Euridis2.
Significant fact as regards development of renewable energies thanks to the decentralized production, Linky counts at the same time in racking (consumption) and injection (production).
The system built by ERDF rests on the bidirectional communication between its park of counting and a single information system via concentrators installed in the switchyards HTA/BT. Information and the commands circulate between these 3 points in the following way:
of Linky to the concentrator, by powerline communication (CYBERATHLETE PROFESSIONAL LEAGUE) lower rate on network BT
concentrator with the central system by mobile telephony (GPRS).
Flows are supervised by a single central agency of supervision (also called "control room").
The powerline communication used is based on a modulation S-FSK, with a flow of 2400 bits a second. Above this physical layer are used the layers of the PLANE protocol (standard IEC 61334) as well as an electronic mail COSEM (standard IEC 62056).
The Linky system is at the same time a manager of credits and data of counting and a delivering automat of the services to the others SO of the company and, via them, to SO of the providers of electricity. Thanks to him, a customer moving in his new housing will be able to call his provider, to ask him for a mise en service and to obtain it without the constraint of a physical appointment, in the 24:00.
Linky brings to the customers the services of any meter AM as described heading of the article and makes it possible ERDF to prepare with launching its clean "intelligent network", pledge of very many other possibilities for the various users of the networks and the community in general.
Examples of services:
the statement of remote index, without the subscriber not being present
the remote mise en service, within deadlines shorter,
the remote breakdown service,
the follow-up of the consumption of the hearth and thus a better control of the energy expenses.
Concerned of the respect of the private life, consumers associations issue reserves on the deployment of Linky. The National Commission of data processing and freedoms (Cnil) declared, in an official statement published on August 5th: The information of power consumption transmitted by the meters is very detailed and makes it possible to know much of things about the occupants (of a hearth). () The distributers of energy will have to thus bring serious guarantees on the security of these data and their confidentiality.
ERDF answered that all the data of consumption are encrypted, to protect the system against malevolent attacks which can harm the respect of the private life. The company added that all the collected informations will be regarded as personal data and thus transmitted to the producers and distributers of energy in the compliance with rules of confidentiality, under the control of the CNIL.