Electrical pioneer’s life honoured
Three generations of the Mandeno family gathered in Tauranga last month to celebrate and commemorate the life and achievements of Lloyd Mandeno OBE.
Lloyd was a pioneer of electrical development and distribution in New Zealand. From 1915-1926 he was based in Tauranga as a borough engineer.
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 hydro scheme which was commissioned in 1925.
While in Tauranga, Lloyd devised and patented the singlewire 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 11kV distribution, the development of the first electric hot-water storage heaters, a peak load limiting device, 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.
Lloyd was born on October 3, 1888 so it was fitting for the family to hold an event close to his 130th birthday.
“It was our collective desire to involve the three generations and to use this opportunity to visit sites and places around the Tauranga District where Lloyd practised his skills,” says Richard Mandeno, one of Lloyd’s 10 grandchildren.
The family celebrated the birthday with a cake that was cut by three of Lloyd’s descendants whose collective age totalled 130 years.
The family visited the site of possibly the world’s first fully electric house in Devonport Rd, which was established by Lloyd, where he lived in Norris St, and the Tauranga Museum’s collection where an example of the world’s first electric hot water cylinder that was invented by Lloyd is stored, along with other appliances from the first electric show room that was located in Devonport Rd.
Lloyd also installed the original high-pressure hot water boiler and X-ray machine at the Tauranga Hospital in 1921.
The family celebrated twith a dinner at the Mount Maunganui Golf Club where they heard from Dr Simon Taylor from the University of Waikato, who has done significant research on Lloyd’s inventions and his contribution to the electrification of the Bay of Plenty.
David Reeve, who is the coproducer of the documentary series Powering New Zealand, then treated the gathering to a preview of a section in Episode III which covered Lloyd’s pioneering work.
In 1920, Lloyd conceptualised what was to become the Kaimai Power Scheme, which is now owned and operated by Trustpower.
Lloyd traversed the region on foot with his treasured pocket aneroid barometer and from this he was able to record the water levels of the streams and rivers that are now linked through a network of tunnels and lakes to form the hydro power schemes that exit into the Wairoa River.
The Kaimai Scheme now includes over 9km of tunnels and generates 168GWh per annum, powering about 21,000 houses.
To understand the magnitude of Lloyd’s work, Trustpower hosted the three generations on a tour of the upper portion of the Kaimai Power Scheme.
The tour showcased Trustpower’s range of hydro infrastructure, with particular focus on Lake Mangonui which provides the reservoir for water diversions from the Omanawa, Ngatuhoa and Opuiaki catchment areas, and the Lloyd Mandeno Forebay that provides a view of the twin penstocks that convey water down to the Lloyd Mandeno Power Station generators from a height of 150m.
Lloyd chose these geographical water flow paths when he scoped the scheme layout to utilise this elevated position for maximum efficiency.
The final stop of the tour was the Lloyd Mandeno Power Station that was commissioned in 1972, a year before Lloyd died. This station is situated on the west bank of the Mangapapa River and has two Francis turbines and generation units, each producing 8MW. The collected river flows then power the Lower Mangapapa (5.6MW) and Ruahihi (20MW) Trustpower stations downstream.
Richard thanked his cousins who helped organise the weekend, plus guest speakers Fiona Kean, Max Avery, Simon Taylor and David Reeve.
“We must acknowledge Trustpower for their efforts and organisation on Sunday to allow us the opportunity to understand our grandfather’s original vision 100 years ago and the implementation of that vision for the good of the Tauranga community.”
More on P14, plus see story about documentary featuring the work of Lloyd Mandeno.
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