The Ardnacrusha hydroelectric power station in Co Clare has received two awards.
The ESB and Siemens jointly received the International Milestone Award for the construction of the Shannon Scheme. The award recognises the scale of project and how it became a model for large-scale electrical schemes around the world.
The project, which was officially opened in July 1929, also received the International Landmark Award from the American Society of Civil Engineers.
Previous winners of these awards include the Eiffel Tower, Golden Gate Bridge and the Panama Canal.
ESB chief executive, Mr Padraig Mc Manus said the awards were a great source of pride to both companies.
Mr Richard Crowe, managing director of Siemens said the significance of the Shannon Scheme could not be overstated.
"Most serious historians acknowledge that it [the Shannon Scheme] provided the platform for the economic, industrial and social development of the country," he added.