PIERRE M. AILLERET (1900-1996)

BY PIERRE M. BORNARD

PIERRE MARIE JEAN AILLERET, a key contributor to the creation of the French interconnected power system and a former deputy CEO of Electricité de France (EDF), who described himself as an “industrial researcher,” died at 96.

Pierre was born to Amédée Eugène and Angèle Devaine Ailleret in Vienne-en-Arthies, a small village near the Seine River, about 50 kilometers northwest of Paris. His father, an engineer and inventor, later became an artillery officer and was awarded the Legion of Honor, France’s highest distinction, for his services, including during World War I, to his country. Pierre grew up alongside his brother in a household guided by integrity, courage, and service to both the community and the nation. During World War II, his brother Charles risked his life as the leader of a large “Resistance” organization fighting to liberate France from Nazi occupation.

Pierre excelled as a student at his high school in Paris and went on to attend École Polytechnique, France’s most prestigious engineering school, graduating in 1920. He earned an additional engineering degree from the École Supérieure d’ Électricité in 1922.

In 1935, he married Denise Nodé-Langlois, and together they had six children—three sons and three daughters.

After eight years in industry working in hydropower generation and power grids, Pierre developed an understanding of the crucial economic and reliability benefits of network interconnection. He was then assigned a mission in Southeast Asia, where, in what are now Vietnam, Cambodia, and Laos, he designed and implemented a master plan for interconnecting power generation resources with 60-kilovolt transmission lines, enabling the early electrification of new areas.

In 1930, Pierre was appointed CEO of UNIE (Union for Industry and Electricity), an industrial group promoting grid interconnection at a time when electric systems were still largely regional. He designed and built the first 150-kilovolt transmission line, carrying hydroelectric power from the Alps to Paris, 500 kilometers away, generating significant economic benefits through the optimized use of hydro and thermal power plants.

In the early 1940s, while struggling with serious health issues, Pierre anticipated the eventual outcome of World War II and used his time to develop planning methods for the transmission grid that would be necessary to rebuild France after the war. He worked on standardizing electric apparatus and network towers (including grid voltages that were diverse and not fit for interconnections) to enable efficient post-war reconstruction while ensuring the best use of limited financial resources. He also developed the first analog tools for power flow computations in large meshed grids, based on the DC current approximation, and designed power system operation tools, including load-frequency control systems.

By 1946, everything was in place for the reconstruction and expansion of the French transmission grid, which had been severely damaged during the war. Under a new law, all former electric utilities were merged into a single national company, Electricité de France (EDF).

Charles de Gaulle, then head of state, appointed Pierre as one of EDF’s first four directors. He was placed in charge of engineering and research, a department that remains active today. With everything needing to be built from scratch, Pierre’s visionary leadership was instrumental. He anticipated rapid growth of electricity demand in postwar Europe, correctly predicting that power consumption would double every 10 years. Based on this insight and his engineering experience, he developed the planning criteria for an optimal interconnection grid, laying the foundation for today’s pan-European power system.

By the 1950s, Pierre had grown concerned about the potential scarcity of fossil fuels and the security of oil supplies for Europe. He championed renewable energy projects, overseeing the design and construction of the world’s first tidal power plant in Brittany with a capacity of 240 megawatts, commissioned in 1966, and Europe’s first one-megawatt wind turbine, also completed in 1966. Inspired by the commissioning of a prototype British nuclear power facility in 1956, he was the first French leader to recognize the potential of nuclear power in meeting growing electricity demand. He advocated for a government decision to develop nuclear power, which today generates 70 percent of France’s electricity.

Pierre retired as deputy CEO of EDF in 1967 but continued to advise governments across Europe, Africa, and North America. At the age of 70, he became fluent in Spanish to serve as a board member for Spanish-speaking companies. Dedicated to sharing his knowledge, experience, and methods to address multidimensional complex problems, he taught at various engineering schools and published multiple books on electric power systems. In 1982, he wrote Tentative Theory of Standarization (Eyrolles), reflecting his expertise in technology and regulatory frameworks.

Pierre’s achievements earned him numerous honors. He was the first recipient of the Blondel Medal, awarded by the French Electricity and Electronics Society to recognize outstanding electrical scientists and engineers. He received honors from the French Academy of Sciences, was named an Institute of Electrical and Electronics Engineers Life Fellow, and was elected to the National Academy of Engineering in 1977. He was also a Commander of the Legion of Honor.

Pierre was widely admired for his inspirational and benevolent management style. He trained and mentored generations of young engineers, teaching them how to apply their technical knowledge to address complex systems design and management challenges. He emphasized technical knowledge, open-mindedness, risk analysis, and ethical decision-making, recognizing that in an industry where decisions involve billions of dollars, the public good must always come first. He instilled these values not only in his teams but also in his children.

Thanks to his exceptional qualifications, he was invited to serve in numerous institutions. He was a member of the French Atomic Energy Committee, chairman of the French Technical Union for Electricity, president of the Société Française de l’Électricité, president of the Training Council (Conservatoire National des Arts et Métiers), and vice president of the French Standards Organization (AFNOR).

Combining pragmatic experience with advanced mathematical theory, Pierre was a visionary who addressed multidimensional technical, economic, social, and political challenges. He was always promoting the public good, people’s shared socio-economic welfare, and the highest ethical standards.

Just as his father instilled strong family values in him, Pierre passed them down to his children. His son François followed in his footsteps, eventually joining EDF and becoming CEO of the company. Later François also served as chairman of the board of the Pasteur Institute, a leading nonprofit organization, and chairman of AFNOR. François’s siblings also had brilliant careers in industry and academia.