Visit to Ardnacrusha - October 2012
Author: Pat Murphy Posted on: 13/11/12 Print Version

Photographs by Pat Murphy

The group with Catherine Halpin, Station Manager

On 4th October last Gerry O'Neill and his ROMEOS (Retired Old Men Eating Out) began their Winter/Spring programme of outings with a visit to the Ardnacrusha Hydro Electric Scheme. The visit to Ardnacrusha was organised by Jim Stanley, retired ESB employee, who worked for some time at the Scheme.

Pre tour substance in Limerick

On arrival in Limerick by train the party of 24 retired to the a nearby Hotel for lunch and liquid substance as a pre-curser to the forthcoming experience. As arranged, by Gerry, we were collected by bus for the trip to Ardnacrusha and on route were given a tour of the more interesting parts of the City.

Ardnacrusha Hydro Electric Station

The 30 minute journey had us arriving at the Scheme at 1430 hours where we were met by Catherine Halpin the Station Manager who enthralled us over the following two hours with her knowledge and presentation of the Hydro Electric Scheme.

The initial proposal for the Scheme was presented by Siemens to the Government of the Irish Free State on 1st September 1924. The contract was signed and construction work began on 1st August 1925. The official opening ceremony of the Shannon Scheme took place on 22nd July 1929 and went into commercial operation on 24th October 1929.

Catherine explaining the Headrace

The Headrace

Catherine explaining the fish pass lift

The Penstock controls

The work involved the removal of 7.6 million cubic metres of earth, 1.2 million cubic metres of rock, the construction of 60 miles of a purpose built narrow gauge railway some of which was electrified, the construction of a power house, four major bridges and in addition nine rivers and many streams were diverted. The workforce comprised of approximately 5000, about 1000 Germans and 4000 Irish worked on site and special work camps had to be set up for the duration of the project. There were 33 deaths, including 3 Germans during construction.

The work begins

The Tailrace

The upper lock gate

Descending to Control Room

Prior to entering the Control Room

The Old Control Room

The 3 new turbines

The generating plant comprises of three vertical-shaft Francis Turbo generators ( installed in 1929) and one vertical-shaft Kaplan turbo-generator (installed in 1934) operating under an average head of 28.5 metres.

Ardnacrusha generates at 10.5kv (kilovolts), but this is tramformed to 40kv for local distribution, and to 110kv for long distance transmission on the national Grid. Between 1992 and 1998 the station was refurbished; new more efficient turbines and state of the art control system was installed. In 2003 Ardnacrusha control and monitoring was transferred to the new Hydro Control Centre located at Turlough Hill, Co. Wicklow.

The four Penstocks with the farthest one under cover for servicing

The 28.5m lock
Parteen weir, 7 miles upriver, controls the flow of water from the Shannon into both the Headrace and the old river channel.

There are six sluice gates on the river outlet. A fish pass of 13 steps is built into the weir to allow migrating fish to pass into the upper Shannon.

Parteen Weir

Gerry O'Neill & Jim Stanley presenting
the Howth burgee to Catherine Halpin the Station Manager
On returning to Limerick and with time to kill before embarking on the return train the majority of the ROMEOS passed the time in the Railway Hostelry. This was another very successful and enjoyable outing organised by the chief ROMEO Gerry O'Neill. The next ROMEO's outing is on Tuesday next the 20th November to the Titanic Exhibition Centre in Belfast.