1927-1945: Ardnacrusha, Shannon Scheme, World War II
In 1929 ESB began supplying the cities, towns and villages with electricity generated at Ardnacrusha and transmitted through the new national Shannon Scheme network.
ESB acquired Pigeon House, an oil burning station previously managed by Dublin Corporation Lighting Committee and Cork Station previously managed by by The Cork Electric Tramways and Lighting Company.
In 1931 a small fuel station with a 300 KW capacity was erected at Letterkenny. As the national network had not yet reached Donegal, it was considered more economic to erect this station.
World War II delayed plans for other hydro schemes but the Liffey Scheme began generating electricity in 1943.
1946-1964 : Rural Electrification, Hydro and Turf Programmes
The immediate postwar era was concerned with recovery from the setbacks of war. In 1946 the Rural Electrification Scheme began connecting rural homes located beyond the towns and villages. By 1964 ESB had connected over 300,000 homes and businesses in all of its 792 rural areas.
As Ireland sought to become self sufficient and reduce the balance of payments deficit ESB developed turf and hydro programmes. The Turf Programme saw ESB open 10 turf stations in this period. By the 1960s turf accounted for one third of national electricity output.
There was further harnessing of Irish rivers for hydro electricity on the Lee and Erne . Two new large steam stations were opened in Marina in Cork and Ringsend in Dublin.
1965-1979: World Oil Crisis, Turlough Hill, One Million Connections
1973 saw a dramatic upheaval in the world energy scene due to the oil crisis. In 1974 ESB opened its innovative hydro pumped storage station at Turlough Hill.
New large steam stations opened at Great Island, Tarbert and Poolbeg. In 1978 ESB began using natural gas, taken from the nearby Kinsale offshore gas field, as an energy source in the Marina station in Cork.
The Rural Electrification Scheme was extended following amendments to the Electricity Supply Act. This allowed homes, who missed out first time around, another chance to get connected on a subsidised basis. All 792 areas were systematically revisited and the scheme continued through various phases until 1978 when 99% of the country was electrified and our one millionth customer was connected.