Energy savings of over 62% for coastal lighting scheme
The challenge
Conwy County Borough Council (CCBC) presented us with challenging design criteria for the newly redeveloped promenade at Colwyn Bay. The re-lighting of the promenade is part of a wider, ongoing project being carried out by CCBC. The overall aim is to redevelop the town’s seafront to create a modern, sustainable and attractive waterfront. CCBC needed to meet a lighting class of ME3a, using 10m columns on one side of the road only. The columns were to be located between the parking spaces and the promenade. This meant they would be set back 6m from the road itself, making it more challenging to meet the required ME class.
Clients and partners
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Client
Conwy County Borough Council
The solution
The initial design for lighting the road and parking spaces proposed use of 250W high pressure sodium (SON), using 1.1m outreach brackets to reduce the setback to 4.9m. The proposal also included 100W SON lanterns on the same columns at 6m to light the walkway.
However, because of the low colour rendering of SON light sources, a decision was taken to switch the specification to LED. Working closely with the scheme’s landscape architects; BCA Landscape, we proposed an alternative design using a combination of Kirium 1 and Kirium 3 LED lanterns. Of particular benefit was the flexibility of Kirium, with its ability to tailor drive currents to increase light output, while still delivering high energy efficiency.
The final design uses 144W Kirium 3 lanterns running at 1A, mounted at 10m, supplemented by 17W Kirium 1 lanterns at 6m, running at 350mA. The result is a visually striking lighting installation with very good colour rendering and uniformity, and an installed electrical load that has been reduced by 189W per column, compared to the original SON design. We also supplied the columns, using a PSX paint finish to protect them from the harsh coastal environment.
In addition to the energy and carbon savings, Conwy County Borough Council will also benefit from reduced maintenance costs as a result of the extended life of LEDs.
" Changing our street lighting from SON to Kirium LED lanterns has provided Conwy County Borough Council with an energy saving of circa 62%. We are impressed with the light output and uniformity to both the road and the promenade "
Len Jackson, Street Lighting Engineer of Conwy County Borough Council