going green - ieee power & energy...

march/april 20141540-7977/14/$31.00©2014IEEE

Digital Object Identifier 10.1109/MPE.2013.2294817

Date of publication: 19 February 2014

26 ieee power & energy magazine

©A

rt

vil

le, l

lC.

TThe TransiTion To a low-carbon economy will creaTe major challenges for the european energy sector in the 21st century. in this sector, electricity is a very important vector for allowing a lower consumption of fossil fuels while main-taining a competitive european economy. The european transmission grid and euro-pean transmission system operators (Tsos) are at the core of the complex european electrical system (see Figure 1). aging infrastructure, low public acceptance of new overhead power lines, and long permitting processes only increase these challenges. all over europe, the required investments are very significant, and r&D activities must be performed to allow an optimization of these investments. enTso-e, europe’s association of transmission system operators, has defined an r&D roadmap for tack-ling the most challenging issues. rTe, the French Tso, has participated in the defini-tion of this roadmap and is a major contributor to ongoing european research projects.

european Tsos face six challenges, critical to guaranteeing the success of this energy transition. each is discussed below.

Enabling the Development of Renewable Energy Unlike conventional generation, renewable energy has by nature a variable generation output with limited controllability. as a result, its large penetration (see Figure 2) calls for changes in the management of system reliability to deal with two main issues: 1) manag-ing the new electrical power flows that stem from it and 2) balancing supply and demand at all times, which is essential to the security of supply. reserves and margins will need to be adjusted using real-time measurements and taking uncertainties and contingencies into account. Demand-side management or, in some cases, curtailment of renewable gen-eration will be required to provide flexibility in the supply-demand balance. improved forecast techniques for the variable generation patterns of renewables will be the key to reducing uncertainties and avoiding oversized reserves and margins. as an example, rTe has developed solutions for forecasting wind and solar generation based on meteo-rological forecasts provided by météo France (the French national meteorological ser-vice). Two software engines, Preole for wind generation and PhosPhor for solar PV generation, have been developed and integrated in an iT platform called iPes as part of a joint initiative with alstom and erDF. rTe has also benefited from participating in the safewind project, one of several collaborative research and demonstration projects cofunded by the european commission (ec) under the seventh Framework Program (FP7), which covers the period 2007–2013. The framework programs have been created to support and encourage research in the so-called european research area; the next pro-gram is being developed and will span the period 2014–2020 under the name “horizon 2020.” The FP7-funded safewind project proposed improvements to forecasting methods

Going GreenTransmission Grids as Enablers of the Transition to a Low-Carbon European Economy

march/april 2014 ieee power & energy magazine 27

By Sébastien Henry, Patrick Panciatici, and Alexandre Parisot

march/april 201428 ieee power & energy magazine

based on a mixture of predictors and focusing on the possible tripping of wind turbines in the case of high-speed wind.

across europe, Tsos are adapting their networks to enable and support the rapid rise of renewable energy. in France, rTe is accelerating the development of its grid to create dedicated hosting areas for production based on renewable energy sources (ress), including offshore wind. There is a strong need for plan-ning and coordination between actors. in France, the regional plans for connection of renewable energy, introduced by law

and known as s3rer, should allow for better planning of the network to achieve the objectives of regional plans for climate, air, and energy (srcae). The work on s3rer is underway. on 1 august 2013, seven s3rer plans were approved and published. The first stage of this process shows that the coordi-nation between network planning and development of ress can be improved, leading to reduced costs for the community.

at the european level, the objec-tive is to push toward an optimal usage of the growing wind power generation in the northern seas, in the baltic sea and surrounding areas, as well as increased produc-tion of electricity from renewable sources in eastern and southern europe, including solar. in the FP7 TwenTies project started in 2009, coordinated by ree (the spanish Tso), six Tsos (from belgium, Denmark, France, Ger-many, spain, and the netherlands), two generator companies, three power technology manufacturers, two wind turbine manufacturers, and various r&D organizations

have collaborated to find answers to the following questions: ✔ what are the valuable contributions that intermit-tent generation and flexible load can bring to system services?

✔ what should network operators implement to allow for offshore wind development?

✔ how can more flexibility in the transmission grid be obtained?

✔ how scalable and replicable are the results of new approaches within the entire pan- european electricity system?

The eU’s transmission system operation with large pen-etration of wind and other renewable electricity sources in networks by means of innovative tools and integrated energy solutions (TwenTies) program was organized around six large-scale demonstration projects that aim to prove the ben-efits of various new technologies, as follows:

✔ SYSERWIND: system services provided by wind farms

✔ DERINT: large-scale virtual power plant integration ✔ DCGRID: technical specifications toward offshore hVdc networks

✔ Storm management: management of offshore wind power in extreme high wind

figure 2. The installed capacity of PV and wind in Europe, 1998–2012 (source: RTE).

200180160140120100

Cap

acity

(in

GW

)

806040200

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

PhotovoltaicWind

RES Installed Capacity in Europe

figure 1. A map of the TSOs of ENTSO-E (source: ENTSO-E).

IS

NOSE

FI

EE

LV

LT

PL

CZ

AT

SK

HU

SI HRBA

RS

RO

BG

MK

GR

CY

IT

CH

DE

NL

BE

FR

GBIE

ESPT

MADZ

TN

TR

AL

MD

UA

BYRU

RU

ENTSO-E Members

ME

LU


figure 3. The mock-up of a dc grid developed as part of the TWENTIES project (source: RTE).

ac Network and Convertor inReal-Time Simulator

ac Network inReal-Time Simulator

Wind Farm and Convertorin Real-Time Simulator

Wind Farm and Convertorin Real-Time Simulator

20 A Permanent, 120 A (4 s)Voltage- or Current-Controlled ±125 Vdc

20 A Permanent, 120 A (4 s)Voltage- or Current-Controlled 100 Vac

dc Breaker to Be Designed

Wind Farm in Real-TimeSimulator

✔ NETFLEX: network-enhanced flexibility through coordination

✔ FLEXGRID: improving the “local” flexibility of the grid.

These six large-scale demonstrations are complemented by three work packages on the nontechnological barriers to the development of an offshore grid and on the replication and scalability at the eU level of the results of the demonstra-tion projects.

while participating in many aspects of the program, rTe most significantly led the DcGriD demo. as part of the research and demonstration activities, a dc circuit breaker was designed by alstom Grid and successfully tested, and innova-tive dc protection algorithms were validated. local controls were designed to enable various dc grids to accommodate wind power transmission and a large range of contingencies (including those on the ac system) without any need for dedi-cated very high-speed telecommunications, as demonstrated with the first dc grid mock-up including physical cables and protection (see Figure 3). as for economic benefits, it was established that new offshore grids allow local surpluses of wind power to be used elsewhere, reserve power to be held, and potentially cheap, low-carbon power to be used instead of more expensive higher-carbon fossil fuel plants.

The DcGriD demo of the TwenTies program, com-pleted in september 2013, provided and demonstrated key building blocks for designing future hVdc networks that can abe securely operated and integrated into existing ac systems. Further, rTe will build on the tools developed as

part of TwenTies to study other converter architectures and study their behavior under stringent transient condi-tions. rTe will also push for research and demonstration activities to study and mitigate potential interaction issues between close hVdc converters and to tackle interoperabil-ity issues in multiterminal, multivendor dc grids. To support these activities, numerical tools will be needed that offer detailed modeling of hVdc components and controls while maintaining a good compromise between robustness, accu-racy, and flexibility. recognizing this, rTe will continue its direct involvement in the development and improvement of such tools. in the end, to validate the various modeling approaches for the different range of phenomena and to demonstrate interoperability and the absence of detrimen-tal interactions, hardware-in-the-loop architectures will be needed, with actual replicas of the physical control sys-tems. in this area, as part of its ongoing hVdc projects, rTe has recently assembled a hardware-in-the-loop test facility called smarTe that uses the hypersim simulator. rTe aims to expand this facility to meet its future project needs and to participate in the future development and improve-ment of the simulator.

in the longer term, the share of power electronics connec-tions into existing ac systems will significantly increase due to the massive penetration of inverter-connected renewable plants and the development of dc links and grids. as a result, the share of grid-connected conventional synchronous gener-ators will decrease locally and globally. synchronous gener-ators govern frequency dynamics and slow down frequency


excursions in response to contingencies due to their inherent physical inertia; they also provide high short-circuit currents that are used for fault detection. in contrast, power electron-ics connections, while they provide additional flexibility, have no direct physical link to frequency and cannot provide short-circuit current above their rated values. The operation principles of future systems will therefore need to be revised to mitigate these effects. rTe will push for and participate in research projects that will address these issues.

Demand-Side ManagementThe development of renewable energy sources, generally intermittent in nature, leads to more variability in the elec-trical supply. Furthermore, French electrical consumption is affected by a significant sensitivity to temperature due to the widespread use of electric heaters; in particular, winter load peaks are increasing. The peak load has increased by 33% in ten years and exceeded 100,000 mw in 2012. with the development of new technologies, new appliances and thus new uses (lcD screens, multimedia, telecom boxes, and even electric vehicles) have emerged or are emerging. This fact makes electricity consumption more volatile.

The process of balancing supply and demand is complex: the challenge is to adapt a more and more fluctuating pattern of electrical generation to a more and more variable pattern of consumption. it is therefore essential to move toward a more flexible management of the supply-demand balance and, in particular, to more flexible electricity consumption.

many uses of electricity (industrial, commercial, and residential) could be shifted to other times of day to pro-vide more flexibility to the electrical system. This requires the cooperation of transmission and distribution operators, consumers, electricity suppliers, and stakeholders in digi-tal communication technology, among others. new storage facilities should also play an important role in the develop-ment of system flexibility.

For several years, rTe has been supporting the flexibility of consumption and demand-side management with the goal of allowing industrial and residential consumers to adjust their consumption and participate in the achievement of sys-tem balance. market mechanisms and operational planning tools have also evolved to develop demand-side management (see Figure 4). rTe is also involved in several French smart grid demonstrations that aim to develop and test technologi-cal solutions (including smart meters, storage, and the intelli-gent charging of electric vehicles) and also to provide global cost-benefit analyses. by giving energy users the opportunity to manage their power consumption and budgets, these dem-onstrations seek to turn passive consumers into active ones.

rTe’s ecowatt and éco2mix initiatives follow this same goal. ecowatt is based on voluntary participation and aims to encourage residents to reduce their electricity consumption dur-ing peak periods, especially in winter during the morning and between 6 and 8 p.m. when the network reaches its limits, the participants receive an alert (via e-mail or sms). in brittany, where the security of supply can be difficult in winter, more than

figure 4. Various types of demand-side management (source: RTE).

SpreadInject

Smooth

Advance

Load

(G

W)

Load

(G

W)

Load

(G

W)

Load

(G

W)

Load

(G

W)

Load

(G

W)

Hour Hour(e) (f)

Hour Hour(c) (d)

Hour Hour(a) (b)

AdvvvvvvA vancaaaa e

SmoSmoSmoSmoSmoSmoSmoSmoSmoSmSSSmmommomSmmSmoSmoSSmoSSSmoSSSSmommmSmoomoSmSSmomomm othothhhothhhhhhothththothhothothooooothothhothoootoothtthhotothothothhhh

SSprSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS eadInject

Delay

Reduce


45,000 people are involved in this program. The éco2mix initia-tive consists of an information service available on the rTe web site. it gives information, in real time, on French load and power production as well as exchanges with other european countries. Production is broken down by generation type (wind, hydraulic, gas, oil, nuclear, and so on) and corresponding co2 emissions are given. Values are updated every 15 min and are also avail-able through a smartphone application. an illustration of the éco2mix software is given in Figure 5.

Grid Infrastructure Developmentcontrary to common belief, the development of distributed generation (DG) does not make transmission grids use-less; transmission systems are necessary for the delivery of renewable electricity production to consumption locations. indeed, on one hand, as the siting of DG stems from the natural distribution of wind and solar resources, such facili-ties are often located in rural areas far away from cities with large amounts of consumption. on other hand, the seasonal and daily variation of DG sometimes leads producers to evacuate the production surplus to other areas to avoid cur-tailing it, and sometimes other sources of energy are manda-tory to maintain the balance between electricity supply and demand and to avoid blackouts.

The european electrical transmission grid, as a vector of integration among the national, regional, and european levels, allows for local energy policies while ensuring over-all adequacy. it helps to compensate for regional imbalances by using complementarities and supports between areas. it minimizes the required installed generation capacity in France while improving the security of supply and quality of electricity by making possible the sharing of resources and means. Finally, it contributes continuously to the minimiza-tion of costs and co2 emissions, as the means of production used to meet demand are the most effective means: they are selected from among all those of the interconnected system. The improvement of coordination between Tsos is essen-tial to enhance the level of security and optimization of the european system. The emergence of regional coordination service centers, such as coreso for western europe and Tsc for central europe, is playing a key role in the safe and efficient management of the european electricity system.

local solutions (like “smart cities” or local balancing) must be also developed but cannot be singled out as the only answer to all challenges. Thanks to the transmission grids, these initiatives will indeed be made achievable at the lowest cost while meeting the expectations of each individual and industrial user throughout the entire electrical system for a high level of reliability and quality of supply. The transmis-sion system will thus play a key role in the smart system, allowing the integration of local initiatives by means of global optimization across France and europe (see Figure 6).

sharing renewable energy sources across europe through transmission grids requires more than ever a long-term, pan-european, coordinated expansion plan. compared with

present planning approaches, this is quite challenging due to the long-term horizon, the large geographic area, and the changing nature of generation patterns. new technological developments and new avenues for flexibility must also be taken into account. in response to this objective and chal-lenge, rTe stepped forward as coordinator of an ongoing FP7 project, e-highway 2050, whose overarching objective is to develop a top-down planning methodology to provide a first draft of a modular and robust expansion plan for the pan-european transmission network from 2020 to 2050, in line with the pillars of european energy policy. The project aims to plan a pan-european transmission network, includ-ing possible highways, that will be capable of meeting euro-pean needs between 2020 and 2050 (see Figure 7). The six steps in the development of this plan are:

1) The project will first implement a set of future power sys-tem scenarios to be reviewed by the project consortium’s stakeholders. These will include the requirements for generation units to support backup and load balancing as well as the possible advent of electricity storage.

2) The scenarios will then allow for the design of several grid architecture options, for which cost-benefit anal-yses will be performed within an optimization frame-work that covers the entire perimeter of the enTso-e organization.

3) The results will be presented and debated within the entire electricity value chain and also with representa-tives of stakeholders in europe, thus addressing the main drivers and potential barriers to the proposed grid architecture options.

4) starting with the pan-european grid in 2020 as described by enTso-e’s 2012 Ten-year network Development Plan (TynDP-2012), a modular approach leading to a portfolio of expansion plans is proposed wherein the

figure 5. An Illustration of the éco2mix software (source: RTE).


2020–2050 proposals optimize investment costs over this time frame.

5) The study also provides grid design options and exam-ines possible technology bottlenecks, technical plan-ning, operations and governance, and potential supply chain gaps, with an emphasis on environmental and public acceptance issues.

6) Finally, governance and regulatory aspects are ana-lyzed, resulting in a set of proposals to be reviewed by the regulatory authorities.

The Intelligent Transmission Gridbeyond the development, operation, and maintenance of the physical infrastructure, rTe is the architect of the market “soft-ware” that allows the optimal use of these infrastructures. The mechanisms of this software allow flexibility, ensure liquidity to market participants that hold units of production and consump-tion portfolios, permit optimization of electricity imports and exports through interconnections, and foster the development of new services for smarter and more flexible consumption, an

essential requirement for managing peak demand and the variability of renewable energy.

as an example, the market cou-pling currently in operation between the benelux countries, France, and Germany allows an optimization of the electricity exchanges and the best use of different energy sources in northwestern europe. The next step will be the deployment of flow-based market coupling, seen as the target model for highly meshed grids (like the central part of the western european grid). This method takes into account a more detailed physi-cal description of the electricity grid and therefore leads to an improved optimization of the economic sur-plus of the coupled spot markets.

specific simulation methods and tools are needed to be able to study market design evolutions. rTe was the technical coordina-tor of the oPTimaTe project, a collaborative research and dem-onstration project cofunded by the ec under FP7. The project aims at developing a numerical test platform to analyze and to validate new market designs that may allow the integration of mas-sive amounts of flexible genera-tion dispersed in several regional power markets (see Figure 8).

oPTimaTe will therefore contribute to the construction of a pan-european electricity market. oPTimaTe foresees the following two processes:

✔ First, the development of the open simulation platform will support the simulation of interconnected power system operation interacting with electricity markets. The results will be comparative benefit analyses of several market design options.

✔ next, the simulation platform will be extensively used to assess new electricity market design options and study how they can help reach the 2020 eU-27 targets. it will recommend promising technical and regulatory solu-tions moving toward a “virtual single european trans-mission grid” as well as regional balancing processes and taking into consideration the diversity of market features and generation mixes throughout europe.

Aging Infrastructure and New Solutionssome of the existing assets of the transmission grid are quite old; a full-scale age-based replacement program would not

figure 6. Power exchanges patterns expected in 2020 among ENTSO-E countries (source: ENTSO-E).

Country Balances:

Exchanges:Importer<1 Twh <5 Twh <10 Twh >10 Twh

Rather Balanced Exporter


figure 7. The location of renewable energy sources across Europe (source: ENTSO-E).

figure 8. The principles of the OPTIMATE simulation platform (source: RTE).

Wind EnergyWave Energy

Solar EnergyBioenergy

Electricity Highways 2050

OPTIMATE

OPTIMATE

Optimal Vision (LT) Optimate Vision (ST)Simulation

Architecture 2

Architecture 1

Architecture 1

Given

The RecommendedArchitecture Is

only be extremely costly but would also have significant impacts on the reliability and quality of sup-ply due to the numerous long outages that would be required. There is therefore a strong ratio-nale for designing a better asset management program that could save money while maintaining the required level of reliability. This topic is now part of the enTso-e r&D roadmap, and rTe is start-ing a new, ambitious internal proj-ect to address it: smart lab (see Figure 9). The project is struc-tured around five targets:

✔ improving the monitoring of transmission network components, using both classic and new means of observation, such as drones

✔ understanding component aging mechanisms, using a combination of “big data” methods, laboratory experi-ments, and multi physics simulations

✔ forecasting individual com-ponent failure probabilities and life spans

✔ providing decision-making tools for all Tsos’ time


scales, including failure probabilities and associated risk analysis for operational planning, optimization of maintenance operations, and a long-term planning decision process

✔ optimizing the asset management process.The low public acceptance of new overhead power lines

pushes the different Tsos to use, as much as possible, exist-ing assets and corridors. a broad spectrum of new solutions has been investigated, and some have already been imple-mented. at present, most new circuits from 50–225 kV are built underground, and long 225-kV ac underground transmis-sion cables are even used far from urban areas (e.g., the new 225-kV underground line securing the electricity supply of the French riviera is more than 70 km long). hVdc underground links, embedded in meshed ac grids, are also an alternative to 400-kV overhead lines even for relatively short distances (in the case of the new France-spain 2,000-mw interconnection, only 65 km). high-temperature, low-sag conductors (acss, accr, and other types) are used to upgrade existing corridors. Dynamic line-rating equipment, phase-shifting transformers, and other flexible ac transmission systems (FacTss) are also being deployed in rTe’s networks.

when a new wind farm or solar power plant applies for grid connection, the required time to reinforce or build new transmission grid components can be very long com-pared with the time needed to build the plant. To allow the plant to go online with minimal restrictions in the transi-tion period before the grid work is complete, the Tsos are resorting more and more often to automatic devices allowing

corrective actions to operate the system with reduced mar-gins (sPs, predefined post fault actions, and so on). This a major shift compared with prior operational guidelines for normal (nonemergency) conditions, which were mostly based on preventive and manual actions.

rTe is coordinating another project, called innovative Tools for electrical system security within large areas (iTesla). it is a collaborative r&D project cofunded by the ec under the FP7. The main objective of this project is to develop a platform to assess the security of the european Transmission Grid from two days ahead to real time, taking into account uncertainties and corrective actions. This is a very ambitious project that takes advantage of high-perfor-mance computing. it incorporates the following goals:

✔ This platform aims to produce a major innovation: the ability to carry out dynamic operational simulations in the framework of a fully probabilistic approach, thus going further than the current “n-1” approach and optimizing the transit capacities of the grid at different spatial scales (national, regional, pan-euro-pean) and time scales (two days ahead, one day ahead, intraday, and real time).

✔ This flexible iT platform will let Tsos address single, regional, or pan-european network simulations of their own systems, of coordinated regional systems, or of the entire pan-european system, provided that adequate system data are made available at the proper level.

rTe is also participating in a new FP7 project, Generally accepted reliability Principle with Uncertainty modeling

On-Field Real Data Analysis

Monitoring

LaboratoryExperimentations

Numerical ModelsSimulations

Data AnalysisData Analysis

InfrastructureDescription

Power SystemSimulation

Asset ManagementOptimization

Laws on Component Reliability and Life Expectation

figure 9. An overview of the Smart Lab project (source: RTE).


and Through Probabilistic risk assessment (GarPUr), coordinated by statnett, which began in september 2013. This project’s objective is to define new reliability criteria to replace the current n-1 criteria while ensuring consistency among the various decision-making processes: planning, asset management, and operation.

Assessing and Managing TSO Impacts Tsos need new solutions to meet the challenges of the euro-pean electricity system, in particular, a strong public opposi-tion to the building of new power lines, resulting from their adverse environmental impacts. without new options, Tsos will not be able to carry out their missions.

Furthermore, studies on risks related to interactions between electromagnetic fields and the environment tend to amplify the doubts held by the general public about potential negative effects of electric fields on humans, animals, and plants. research and innovation are needed to deal with the following potential challenges:

✔ providing safe and available electrical energy at an affordable cost

✔ generating enough electrical power to meet new con-sumer needs

✔ transmitting electricity in a way that preserves major environmental balances.

The standard solution used in the past—the building of power lines—is now no longer sufficient or sometimes even relevant. only a mixture of new technical and organizational options will lead to acceptable innovative solutions, which in turn requires the availability of new methods and knowledge to assess and control the overall impact of these options, be they environmental, economic, or societal.

These methods should introduce ecodesign as a basic principle, while new knowledge covering biodiversity, health, and the socioeconomics of energy systems must be developed. with respect to these four axes of improvement, rTe’s contribution will always be built in partnership with external experts. it will cover new methodological knowl-edge, including:

✔ methods of analysis of the life cycle of components and typical electricity transmission grid subsystems

✔ extending that analysis to cover social impacts, biodi-versity, and health, including the psychological field.

on this topic, rTe is participating in a new european-funded FP7 project, insPire-Grid, that is being coordinated by italy’s ricerca sul sistema energetico (rse). The project is investigating grid expansion problems from the perspec-tive of the social sciences. its overarching aim is to improve the understanding of how the social processes related to grid expansions work—why some grid projects are blocked while others go ahead. it will identify practical measures to build trust and stakeholder support for grid projects and explore what this means for the accelerated european renewable expansion. more specifically, the project proposes to develop a theoretical and methodological framework for analyzing

the social processes of acceptance of (and opposition to) grid expansion projects; identify and demonstrate new or improved approaches that will engage stakeholders in the permitting pro-cess in a way that clearly and transparently accounts for their views; and suggest practical measures to build stakeholder support to facilitate the deployment of new grid infrastructures.

ConclusionsTo tackle the six challenges described above, significant r&D effort will be required at the system level, with the Tsos as key actors. in addition, the temporal consistency of the pro-posed solutions and their realization must be also be ensured. although it has taken, on average, between 12 and 18 months to build a PV solar power plant, three years to put in opera-tion 1 Gw of demand response, and six years to create an up-and-running market coupling between the benelux coun-tries, France, and Germany, more than ten years are generally required to build a 400-kV overhead power line. To adapt the transmission grid and meet these challenges in an optimal way, a rationalization of the authorization processes therefore seems mandatory. rTe intends to work with other Tsos, with stake-holders, and with policy makers to accomplish this change.

The success of the european energy transition also hinges on the involvement and collaboration of all relevant research actors throughout europe and worldwide. Tsos should be at the core of this community, and rTe intends to work closely with them in europe through enTso-e but also selectively worldwide on specific topics. rTe will work with manu-facturers and other industrial actors through collaborative research projects and by supporting demonstration opportu-nities. joint projects and partnerships with academic institu-tions in the field of power systems or other scientific fields will also be key in our r&D strategy, as academic partners will provide both innovative ideas to design future power systems and educational opportunities for the researchers and engineers who will build and operate them. Finally, to achieve optimal global solutions at the system level, cross-disciplinary research activities will more important than ever, and rTe intends to promote them actively.

For Further ReadingsaFewinD. [online]. available: www.safewind.eu

TwenTies. [online]. available: www.twenties-project.euelectricity highways 2050. [online]. available: www.

e-highway2050.euoptimate. [online]. available: www.optimate-platform.euiTesla. [online]. available: www.itesla-project.euGarPUr. [online]. available: http://www.garpur-proj-

ect.eu/

BiographiesSébastien Henry is with rTe, France.

Patrick Panciatici is with rTe, France.Alexandre Parisot is with rTe, France.

p&e

going green - ieee power & energy...

Documents