Across France, TOPKAPI SCADA software assist progress men who have one goal: to provide power in quantity and quality, according to a program designed by the minute.

E.ON is one of the world's largest power and gas companies, with more than 85,000 employees worldwide, and 2,300 TWh sold. E.ON France is the third producer and supplier of electricity and gas in France with a 32 GW installed capacity.

AREAL is the creator of the SCADA software TOPKAPI widely used in the energy sector.


In 2007 SNET chose AREAL to realize its monitoring and optimization system for electric power generation.

Salle des commandes principale du CODAP (Centre d’Optimisation, de Dispatching et d’Ajustement de la Production).

In 2007, Endesa is one of the largest electricity companies in the world, present in 15 countries on 3 continents. Leader of the Spanish electricity sector (Production, distribution, transportation and distribution), it is in France the third producer and supplier of electricity in a market recently liberalized. It operates power stations in Provence (Gardanne), in the Centre region (Lucy), the north (Hornaing) and Lorraine (Saint-Avold) where the CODAP, Center for Optimization, Dispatching and Production Adjustment, is located.

Composed of about fifteen people, the CODAP has a team of dispatchers who work in continuous service and perform real-time monitoring and scheduling of production units.

Herein lies the heart of the new system implemented by AREAL, whose primary function is to help manage the perimeter balance of ENDESA France, ie to ensure real-time balance between production in a broad sense (production groups, but also purchase of energy) and ENDESA's customers consumption (EDF, Endesa Trading and eligible customers).

The CODAP is permanently connected to the power plants, to the trading room and to the RTE (Réseau de Transport de l'Electricité - Electricity Transport Network), which provides the production schedule and requests for adjustments of energy.

Key to the success of the project, a meticulous set of specifications was developed by ENDESA, which AREAL implemented without drift or compromise.

The system was named VISIOPROD and was adopted by all stakeholders and operators thanks to the qualities seen as essential for this project: ergonomics, system performance, relevance and accuracy of information provided.

Stability and reliability of the system, associated to high-end hardware, were the qualities demanded by Endesa to get a very high availability system.


TOPKAPI  lies on top of an integrated and hierarchical structure, whose components are:


  • At each site, two redundant controllers for data acquisition.
  • A wide area network (WAN) linking the sites.
  • Two redundant application servers, one located in the Paris region, the other in the Moselle district. TOPKAPI, running on these servers, acquires data using the MODBUS IP protocol with an additional layer for the management of data time-stamped at the source. What is the reason for processing data time-stamped at the source, while the system is in real time? Simply to cope with temporary failures of WAN and prevent from loosing historical information; PLCs have substantial autonomy, over 8 hours, to store data in case of network failure. The reliability rate of the acquisition is up to now higher than 99.99% as no data was lost since the system was started! No need to say, a precise time synchronization is required between servers and PLCs, which is performed by TOPKAPI.
  • A server for thin clients supporting a SQL Server 2005 database and an Intranet server. This server runs an application developed by AREAL, whose data are provided by TOPKAPI.
  • Three control stations located in the CODAP control room.
  • One control station in each power unit.
  • One thin client station located in the trading room.
  • Thin client stations available to the operators and managers of the company.

The objective of the system is to facilitate the work of operators who aim to fine tune the production in order to exactly match the power requested by the customers, while minimizing the gaps between the planning and completion.

TOPKAPI shows in this application its amazing ability to perform real time processing over historical data accumulated in the past and over scheduling data. But the supply of energy is also the result of an intensive trading. TOPKAPI assists the trading managers with the display over "thin clients" of animated screens, featuring an exact copy of the screens available to the control room operators.

Market trends, prices up and down available from RTE web servers are acquired by Topkapi using a HTML communication driver.


TOPKAPI Network Architecture


Two redundant controllers perform a one second rate acquisition of data from each site, and forward those data to two redundant Topkapi server stations located at the CODAP control room (East of France) and at the premises of the application service provider (Paris Region).

The operating stations of each control room display graph trends and bar charts featuring the production averaged minute by minute. The data are also stored on a third server for archiving, and provided to the "Thin Client" stations when requested.




Global view of instant power of each unit.







A web browser displays the production history and schedule of each unit.






Additional values can be displayed on demand to improve the follow up.








This graph displays the 24 hours schedule, the schedule corrected in real time by the network power request (adjustment called Primary setting) and by the "national level" signal (secondary setting), the power achieved, the differences Production / program, the energy produced compared with the programmed energy. The top left alarm view provides traceability of incidents. Animated icons highlight program changes, enabling operators to react just in time.


(1) - The project was designed and realized by SNET (Société Nationale d'Electricité et de Thermique) which was owned at the time by ENDESA, a major global operator of electricity and gas.