To coincide with the online publication of the NIAH Clare County Survey, the hydroelectric generating station at Ardnacrusha has been selected as the Building of the Month for June 2009.

The potential for harnessing power on the River Shannon had long been recognised with plans dating back to a report (1844) published by Sir Robert Kane (1809-90), a Dublin-born chemist.  A later proposal, known as “Frazer’s Scheme”, was inspired by similar work at Niagra Falls and was endorsed under the Shannon Water and Electric Power Act, 1901.  As the cost was seen as prohibitive, however, the project was never realised.

The present scheme eventually came to fruition through the exertions of a Drogheda-born engineer, Dr. Thomas Aloysius McLoughlin (1896-1971), who in 1922 joined the firm of Siemens-Schukertwerke in Berlin.  Commissioned by Patrick McGilligan (1889-1979), Minister for Industry and Commerce, to submit a plan for a generating station on the River Shannon, McLoughlin proposed a scheme that at over five million pounds was almost one-fifth of the entire annual budget available to the Irish Free State.

The considerable expenditure, sanctioned by the government following much political debate, was necessitated not only by the generating station, but also by the head- and tail-race canals constructed along the River Shannon, spanned by four new bridges, and the extensive system of culverts and sluices enhancing the fall in water levels between Lough Derg and the Shannon.  Fish ladders were also required to allow the safe passage of salmon past the power station.

Work on the project, which would officially be known as the Shannon Scheme, began in 1925 and the Electricity Supply Board (ESB), which would take over responsibility for the station, was established by Minister McGilligan in 1927.  Despite a major labour dispute, a penalty clause in the contracts ensured that work was completed on time in 1929 with only a comparatively minor budget overrun.

The centrepiece of the Shannon Scheme remains the impressive generating station at Ardnacrusha, a steel-framed building designed to house six massive turbines: ultimately, only four turbines were installed with three (1929) belonging to the vertical shaft type patented by James Bicheno Francis (1815-92) and one later turbine (1934) belonging to the vertical shaft type developed by Viktor Kaplan (1876-1934).  Interestingly, the role played by Siemens-Schukertwerke in the scheme appears to have influenced the appearance of the station, the remarkably high-pitched roof with rows of lucarne-like miniature dormer windows exhibiting a marked Germanic character.

 

At the time of completion, the station at Ardnacrusha had the distinction of being the largest hydroelectric station in the world although that title would quickly be conceded to the Boulder Dam, latterly known as the Hoover Dam, begun in 1930.  Its importance in supporting the economy of a new independent Ireland cannot be overstated with the generating station intrinsically linked to rural electrification in the 1930s.  The iconic status of the Shannon Scheme for the new state is highlighted by paintings by Sean Keating RHA (1889-1977) of the site under construction.

 

The success of the station generated international interest and was adopted as a model for similar electrification projects throughout the world.  The Financial Times commented:

For half a century the country under the British regime toyed with the suggestion of harnessing the Shannon.  The British are a hardheaded and practical folk, but they jibbed at such a venture.  Then the Free State came into being, and ardent untried administrators, remembering that they had always been accused of being dreamers, seized on this chance of showing what they can do.

The significance of the Shannon Scheme continues to be recognised and in 2002, its seventy-fifth anniversary, the American Institute of Electrical and Electronics Engineers (IEEE) identified the project as a milestone of twentieth-century engineering while the American Society of Civil Engineers (ASCE) identified the site as an International Historic Engineering Landmark.

Click here for the record for the Shannon Scheme

All images reproduced courtesy of the ESB Archive

Further reading: Manning, Maurice and McDowell, Moore, Electricity Supply in Ireland: The History of the ESB (Dublin: Gill and Macmillan, 1984).