The change to LED street lights coming in way under budget
New Plymouth ratepayers have been saved money thanks to smart buying and an increased subsidy.
Two years ago the council started replacing the more than 8,000 sodium streetlights in the district with LED lights in an invest-to-save initiative expected to cost about $5.5 million.
Getting better deals on the lighting and the installation got the cost down to $3.8million, infrastructure manager David Langford said.
"That on its own is huge saving and a really good result."
Then the New Zealand Transport Agency, which subsidises LED street lighting, increased its subsidy from 51 per cent to 85 per cent, which was icing on the cake, Langford said.
The Taranaki Electricity Trust also contributed $100,000 for lights in Inglewood and Urenui.
The new LED lights are now estimated to cost New Plymouth ratepayers $573,000.
Replacing the old lights is expected to have a cost saving of $16.3m over 20 years - $11.8m in maintenance renewal costs and $4.5m in electricity costs.
About 2,800 street lights will have been switched over by the end of June, Langford said.
"To say we're pleased with the progress of this programme is an understatement. We've got about a third of the lights switched over as at the end of May, and we are already seeing a greater than 11 per cent reduction in the total energy used by the district's streetlights."
Between November 2016 and March this year 82,000kWh of electricity had been saved, he said.
"That's enough to power 134 homes for a month.
"The installation programme is a year ahead of schedule, and because of the reducing cost of LED technology and an increased subsidy from NZTA the electricity savings will have paid off our portion of the project in 7.5 years instead of 10."
As well as delivering significant energy savings, the LED streetlights have a cleaner white light and the new system is more reliable with lower costs for maintenance and replacements.
The council is also looking into a central management system, that could control the street lights, dimming them in the early hours of the morning to reduce costs. With the system the street lights could relay information from smart water meters back to the council.
Langford said they were researching what what control systems were available.
"The light doesn't actually read the water meter as such, it just transfers the information."
The street lights could transfer the data instead of having people in vans driving around reading the meters on site, he said.
"The cost savings could be quite large, which means we won't have to charge as much on the rates."