Qualla: Shannon Hydroelectric Scheme

Shannon Hydroelectric Scheme: Introduction

Sat, 23 May 2026 00:00:00 GMT

Photo credit The Banner, CC BY-SA 4.0. In 1925, the Irish Free State was three years old, broke, and just out of a civil war. It had no national power grid. Most of its towns burned oil lamps or candles. The Dail then voted to spend 5.2 million pounds - roughly one-fifth of the entire state budget - on a single hydroelectric project on the River Shannon. A young engineer named Thomas McLaughlin, working for the German firm Siemens-Schuckert, had convinced Patrick McGilligan, Minister for Industry and Commerce, that one dam could light the country. McGilligan convinced the cabinet. The cabinet convinced the experts from Norway and Switzerland. Four years later, the lights came on.

Image: The Banner | CC BY-SA 4.0

Shannon Hydroelectric Scheme: An Improbable Bet

Sat, 23 May 2026 00:00:00 GMT

Photo credit The Banner, CC BY-SA 4.0. Sir Robert Kane had first proposed harnessing the Shannon's fall between Lough Derg and Limerick in 1844. The idea kept resurfacing - Frazer's Scheme of 1901, inspired by Tesla at Niagara; Dick's variant of 1902; the British Board of Trade committee of 1918. None of them got buil...

Image: The Banner | CC BY-SA 4.0

Shannon Hydroelectric Scheme: Building Ardnacrusha

Sat, 23 May 2026 00:00:00 GMT

Photo credit Original photographer unknown., CC BY-SA 4.0. Siemens broke ground in 1925. Three and a half years was the contract; penalty clauses applied. About 150 skilled German workers and engineers came over from Germany; the rest of the labor was Irish - up to 5,200 men at peak, drawn from the surrounding counties. A construction ca...

Image: Original photographer unknown. | CC BY-SA 4.0

Shannon Hydroelectric Scheme: Lighting a Country

Sat, 23 May 2026 00:00:00 GMT

Photo credit Photograph Tobias Helfrich, March 27th, 2004. Modified by Pumbaa, 09:09, 7 April 2006 (UTC), CC BY-SA 3.0. Ardnacrusha's 85 megawatts were more than the entire public electricity supply of Ireland at the time. Within three years demand had grown so much that a second stage went in - a fourth turbine, this one a 30-megawatt Kaplan unit with seven blades, commissioned in 1934. The plant...

Image: Photograph Tobias Helfrich, March 27th, 2004. Modified by Pumbaa, 09:09, 7 April 2006 (UTC) | CC BY-SA 3.0

Shannon Hydroelectric Scheme: What the River Lost

Sat, 23 May 2026 00:00:00 GMT

Photo credit Chemical Engineer, CC BY-SA 4.0. The Shannon between Parteen weir and Limerick - the natural channel bypassed by the head-race canal - used to be world-famous for salmon fishing. The Falls of Doonass at Castleconnell drew anglers from across Europe. The diversion changed everything. There was no fish ladder at f...

Image: Chemical Engineer | CC BY-SA 4.0