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O.B.E., B.E., C.Eng., F.I.E.E.E., M.I.E.E.E., F.N.Z.I.E.

Mr Mandeno who was a pioneer of electrical development and distribution in New Zealand, died at his home in Auckland on 30 December 1973. He was 85.

After being schooled in the Waikato and at Auckland, Mr Mandeno became a foundation student at the Auckland University School of Mines and Engineering. He graduated, however, from the University of Canterbury in 1909.

As assistant to the Waipa county engineer, he then designed some of the earliest reinforced concrete bridges for provincial and rural roads. He was next employed in the erection of the Hora Hora hydro-electric station for the Waihi Gold Mining Company - the first hydro station on the Waikato River. Then, after nearly two years as borough electrical and waterworks engineer at Frankton (which provided the original electricity supply for Hamilton), Mr Mandeno became, in 1915, borough engineer at Tauranga and spent the next 12 years there. During this time he was responsible for greatly increasing the capacity of the Tauranga Borough Council's Omanawa Falls hydro-electric station, and he designed and supervised the construction of the McLaren Falls plant which was commissioned in 1925. At the same time during the 1920s he was associated with various mining ventures in the Otago, Westland, and Coromandel fields, and, after being involved in electricity supply for the whole Tauranga district, he became associated as a consultant for a number of other emerging supply authorities, in particular the Taupo Borough Council, the King Country Electric Power Board, and the Bay of Islands Electric Power Board.

While he was in Tauranga, Mr Mandeno devised and patented the single-wire earth-return (SWER) system of electrical reticulation which is now in use in many parts of the world as a means of distributing electricity cheaply over long distances. Other examples of his genius are his pioneering of 11 kV distribution, the development of the first electric hot-water storage heaters, his early adoption of high-pressure hot-water heating systems and of forced circulation for hot-water heating, and the use of aluminium conductors for low-voltage overhead lines.

Mr Mandeno continued to be involved with electric supply authorities in a consulting capacity until very recently, his professional work spanning over 60 years.

For his development of the S.W.E.R. method of distribution he was awarded the O.B.E. in 1956, and in 1972 the Tauranga joint generation committee named its first power station to be commissioned in the Mangapapa scheme the "Lloyd Mandeno station" in honour of its eminent designer.

At the age of 82, he visited Fiji and reported on the hydro-electric potential of the Nandreau Plateau. On the basis of his report a full-scale feasibility study is now under way.

Mr Mandeno was elected to membership of the N.Z.I.E. in January 1921 and took a lively interest in matters affecting the profession. He was a generous contributor to the benevolent fund. For his paper "Rural power supply", presented to the N.Z. Institution of Engineers in 1947, he received a special NZIE. award.

Obituary from New Zealand Engineering, March 1974, p 96

Refer also to:  Rorke, Jinty; “Mandeno, Lloyd 1888 - 1973”;  Essay M 31, Dictionary of New Zealand Biography, Vol 5,  pp331-2. (