Ports cast light on savings

The port's new $900,000 floodlights are more efficient and produce 10 times less "light spill" outside the working areas.

Two of the country's most highly visible power consumers - the ports of Auckland and Northland - are changing how they light their wharves to try to cut their electricity bills by up to 15 per cent.

The need to create daytime visibility on wharves when working ships at night has made the ports valued customers of power companies but not so popular as neighbours, because of the glare from floodlighting towers.

But technology advances to floodlighting systems and a rethink of practices has allowed the ports to improve on both counts.

Ports of Auckland yesterday produced before and after pictures of its wharves at night to show its new floodlights were "on dip".

The company said the reduction in glare had received praise from neighbours, mariners and the Auckland City Council.

The change gave a much clearer night view of the central city from the Harbour Bridge, the North Shore and other harbour viewing points.

The port spent $900,000 in replacing 1300 floodlights with 650 new ones which produce 10 times less "light spill" outside operational areas.

Company technical manager electrical Tomas Jonsson said the upgrade was expected to cut power use by 15 per cent a year.

"Put into perspective, the electricity savings from replacing the floodlights could power 400 average households a year."

The new lights have a higher ground-focused light output so fewer are needed. Their reflectors control the light beam more effectively.

Northport is hoping for 10 per cent energy savings at the Marsden Pt deepwater port, near Whangarei.

The company has cut down on emergency and security lighting and lights in other non-working areas.

Property manager Francis Patten said changing floodlights had reduced glare for residents only 800m away on the other side of the harbour facing the wharf.

With towers holding 20 lights each of about 1000 watts a lot of power was being saved by having them aimed only at working areas, or switched off when not needed. "Technology is coming on all the time so we are putting on these better lights and using other lights for other work."

At the Port of Tauranga, property manager Tony Reynish said an independent audit showed its high mast lights were efficient but it was always looking to improve the type of fitting on the masts.

The port had 26 towers at Mt Maunganui wharves and 13 at the Sulphur Pt container terminal opened in 1992.

The Energy Efficiency and Conservation Authority has helped the Auckland and Northland ports with their savings drive.

Authority business team manager Alastair Hines said grants of up to $50,000 were available to major energy users to have audits of power use. Ports of Auckland took advantage of a grant last year as did the Port of Otago.

The authority's teams also went on site and talked to managers about how to gain efficiencies in power use. Typically, the authority had found savings of 10 to 30 per cent. Savings came from new lighting technology but also in better use of energy.

Light cuts

The number of floodlights at the Port of Auckland has been halved to 650.

Savings from the new floodlights could power 400 average households a year