Electrification of the Irish Free State

The Shannon Scheme Project

In 1925, the Irish Free State awarded Siemens the contract by for the electrification of the entire country. The core of the supply system was the hydroelectric power plant on the river Shannon with three 30 MVA generators (commissioned in 1929). Extension of the plant was completed in 1933 (another 25 MVA).

Overview

Background
The Concept
Political discussions about the project
The contract and the construction starts
The relevance of the Shannon Scheme for Irish History and Siemens

Background

Ireland’s first public electricity supply system was established in Dublin in 1880 by the Dublin Electric Light Company. In 1882 the system was taken over by the Dublin gas utility Alliance Gas Company and operated by it until 1888. However, the concept of gas and electricity supply in the hands of one utility company was not a popular one in Britain or Ireland, and in 1888 the responsibility for the supply of electricity in the city was taken over by Dublin Cooperation itself. Other cities and towns followed Dublin, and by 1922 there was a total of some one hundred and sixty undertakings in the newly established Irish Free State, but, for example, still only one-third of the houses in Dublin had electricity installed.

So the new Irish Free State government in 1922 found itself with a fragmented and unsatisfactory electricity infrastructure.

The river Shannon today

In this situation it was Dr T.A. McLaughlin, an Irishman from Drogheda, who had the idea of the Shannon Scheme proposal as a new concept for national electrification and presented it to the government in 1923. After his graduation from University College Dublin, McLaughlin took a position as an assistant lecturer in Physics at University College Galway, where he also studied Electrotechnology, and in 1922 he was awarded an engineering degree. In December 1922 he joined Siemens-Schuckertwerke at its Headquarters in Berlin-Siemensstadt.

McLaughlin was fortunate in that the hydro generation division of Siemens was particularly active at that time. He followed a move from thermal to hydro generation in Germany as a consequence of the loss of much of its coal resources to France as a result of a the first World War. He was also fortunate in being facilitated with unusual freedom to pursue his own programme in the gathering of information relevant to his plans for the development of power resources back home in Ireland.

Siemens, for its part, was endeavouring to recover the foreign business it had lost in the First World War and welcomed the potential opportunities offered to it by McLaughlin.

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The Concept

In Berlin McLaughlin began to work on a preliminary design for the Shannon Scheme, making use of existing survey data about the river. The Shannon is the longest river in Ireland. It is 260 km from its source in County Cavan to the start of its estuary in Limerick. Flowing as it does through the flat central plain of the country, the only appreciable fall in the course of the river is the thirty metre drop from Killaloe to Limerick.

On a home visit to Dublin in December 1923, McLaughlin made a presentation on the scheme to a number of government ministers whom he found ”all very interested“ but ”at first a little sceptical“. A month later, formal contact was established between Siemens and the Irish government and, following discussions in Dublin on 8 February 1924, it was agreed that Siemens would submit a detailed report on the proposal, which on receipt would be technically and economically evaluated by a group of international experts to be appointed by the Irish government.

The Shannon Scheme Project

The Shannon Scheme Project: Construction work at Ardnacrusha

The Siemens report “The Electrification of the Irish Free State: The Shannon Scheme Developed by Siemens-Schuckert” was formally handed to the government on 1 October 1924. The proposal was for a single generating station at Ardnacrusha, between Killaloe and Limerick, utilising almost fully the available thirty metre fall. Development would be in two stages. The first stage (partial development) would comprise one 15,000 HP and two 30,000 HP turbines, and the second stage (full development) a further three 30,000 HP turbines. The total estimated costs for the partial and the full development were £4,867,000 and £6,721,000 respectively. The cost for the national grid component of the scheme accounted for approximately 35 per cent of the partial construction figure. The fact that the output from the scheme was in the order of twice the existing generating capacity in the state at the time is an indication of its relative magnitude.

After some discussions by experts the Siemens proposal was generally accepted with some modifications.

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Political discussions about the project

During 1924 the merits of the proposed Scheme were being actively, and often heatedly, debated throughout the country. The enthusiasm of the scheme’s supporters was counteracted by a many faceted line-up of opponents. Opposition was based on a broad list of objections. Some opponents were scared by the sheer magnitude of the Scheme − by a belief that it was simply “too big” for the country. Another group disliked it in that it appeared to weaken the economic link with Britain in favour of Germany. In July 1924, the London Daily Mail warned against “German Intrigue in Ireland − Bid for Economic Control”. In fact, this very weakening of economic relations with Britain was seen as a positive aspect of the Shannon Scheme by many nationalists, including McGilligan, who felt that for the new state political independence should be paralleled by economic independence.

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The contract and the construction starts

The first contract for the Shannon Scheme was placed by the Irish government with Siemens−Schuckert on 13 August 1925 , with a construction schedule of three and a half years. The first contract extended only to the civil works component of the Scheme, with the mechanical and electrical part being covered by a letter of intent. The formal contract for the mechanical and electrical part followed some ten month later on 23 June 1926 .

Content of the contract: briefly summarized, the civil engineering works involved the construction of the power station and other buildings, the 11.5 km headrace canal, the 2.25 km tailrace canal and all the associated weirs and locks.

Preparatory work began immediately with the shipment from Germany to Ireland of the extensive scope of plant and machinery required for the project. Establishment of the site organization was completed in five months, including the building of a temporary site services power station with nine diesel generation sets with a total combined capacity of 4,500 kVA.

An impression of the the magnitude of the construction, which was colourfully described by one journalist as “the Eighth Wonder of the World” − can be gained from the following list:

**Plant used in Ardnacrusha**
6	Large multiple bucket dredgers on rails each about 220 tons
3	Large bank building machines on rails each about 240 tons
27	Smaller dredgers and shovel excavators on rails and caterpillars
130	Steam locomotives
8	Electric locomotives
31	Portable air compressors
13	Portable concrete mixers
8	Tower cranes
3	Cableways, each 310 m long
1,770	Railway waggons
20	Road trucks
31	Barges, trugs, launches and pontoons

**Materials used in Ardnacrusha**
23,000 m3	Timber
2,670 tons	Reinforcing steel for concrete
65,000 tons	Cement
10,100 tons	Fuel oil
110,000 tons	Coal
700 tons	Explosives

Realisation of the relatively short allowed completion period required also an unusually high level of manpower, averaging over 2,500 and reaching a peak of 4,800. The Shannon Scheme came into commercial operation on 17 October 1929 and power has been available from the station since the winter season of that year. In July 1932 an order was placed accordingly with Siemens−Schuckert (Ireland) Ltd for a 30,000 HP Kaplan turbine and 25,000 MVA generator for completition by the end of 1933. The commission of the turbine in November 1933 marked the final development at the Ardnacrusha station.

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The relevance of the Shannon Scheme for Irish History and Siemens

The story of the Shannon Scheme has a place of prominence in twentieth-century Irish history which would be unusual for a mere industrial project − but the Shannon Scheme was not merely an industrial project: “After hundreds of years of domination by a foreign power, the new Free State showed that it could, independently, successfully realise one of the major engineering undertakings of the day.”

For Siemens “the execution of the Shannon Scheme was the one single event that marked the reappearance of the firm on the world electrical scene following the gloom from the first World War and its aftermath.” Although the Shannon Scheme was not a success in economic terms − in total Siemens−Bauunion suffered losses of around RM 24.2 million − the prestige resulting from this technological achievement had a positive effect on Siemens. It had also opened the Irish market to the company.

Sources

Wilfried Feldenkirchen, Siemens. From Workshop to Global Player, Munich 2000.
Any Bielenberger (Editor), The Shannon Scheme and the Electrification of the Irish Free State, Dublin 2002.
Gerald O’Beirne, Siemens in Ireland 1925−2000. Seventy−five Years of Innovation, Dublin 2000.

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