ɪn nˈaɪntiːnhˈʌndɹɪd sˈɪksti fˈaɪv ðə lˈeɪk bɪkˌeɪm ðə sˈoːɹs ʌv kˈuːlɪŋ wˈɔːɾɚ fɚðə tɹˈɔːsfɪnˌɪd nˈuːklɪɹ pˈaʊɚ stˈeɪʃən wˌɪtʃ bɪɡˈæn dʒˈɛnɚɹˌeɪɾɪŋ ᵻlɛktɹˈɪsᵻɾi fɚðə jˌuːkˈeɪ nˈæʃənəl ɡɹˈɪd.
In 1965 the lake became the source of cooling water for the Trawsfynydd nuclear power station which began generating electricity for the UK National Grid.