Street lamp upgrade to lighten costs

A street light upgrade under way in Oamaru will provide a streamlined system that will provide improved functionality and save money.

Waitaki District Council (WDC) roading manager Kushla Tapper said the smart-system will provide more reliable usage data for billing, reduce total power consumption, and reduce electricity drain at peak times thereby reducing costs.

Workers are already swapping out the photocell receivers on the existing street lights in the town and surrounding area with new smart-system control units.

The contract for installation is being carried out by Clements Electrical and Southroads and also includes cleaning, inspecting and maintaining the lights.

Mrs Tapper said the project would be completed below the $360,000 set aside in the council’s budget.

She said the 1550 control units were bought and paid for by council in previous years, so some of the costs have already been paid off.

The smart-system allows all units to be controlled in the same way, rather than using multiple systems.

"We can control certain areas to dim or turn off as needed, without interfering with others. Light levels can be adjusted throughout the night, to reduce electricity drain and use.

"Because the power consumption will be measured rather than calculated, this also saves time and effort, especially with electricity regulators and auditors, so council can obtain better pricing", she said.

Previously, street lights were controlled by a combination of photocells and "ripple relays", which were controlled from the Network Waitaki base on Chelmer St.

"Power usage has been hard to accurately detail, because of the variable sunlight levels. So even within a season, lights could have turned off earlier than yesterday, but we wouldn’t have this accurately recorded", she said.

The system also has additional functions for the future, including turning some lights off completely during parts of the night (for dark sky projects, or during aurora australis events) or even enable a flashing function for use during Civil Defence alerts, something council will be working on in future, Mrs Tapper said.

WDC was one of the first councils to take advantage of an 85% subsidy to replace the old lights, beginning in 2016.

The street lights, except for the heritage lights, are all LED, with further upgrades to be made.

"The heritage lights in lower Thames St, and the historic precinct, will be updated to have LED light ‘gear trays’ installed within the existing heritage lamp casing, as part of a separate project.

"Council has ordered the ‘yellowest’ LED colour range available for those lights, so that the warm glow is unlikely to change", Mrs Tapper said.

The smart-system will cover the streets in Oamaru, but not the State Highway.

While the council usually has delegated power for these lights, that is on hold while New Zealand Transport Agency Waka Kotahi considers a national management plan for State Highway street lighting.