Passage: During the two years that followed, two new boilers were installed (numbers 3 and 4) which, along with 5 and 6, exceeded the output that the old generators from the original Tejo Power Station could withstand. The CRGE concluded that it was necessary that another turbo-alternator be purchased to add to the two generators ordered years before from the German supplier and which were still held up, thus moving forward with the construction of one part of the machinery room to accommodate this new generator. In 1919, the new Swiss Escher Wyss & Cie 7500 kW turbo-alternator began operating.

Question: When was the Tejo Power Station using a new generator?
1919