News Item

How many to change a lightbulb?

It recently took 14 people to change a lightbulb - but it was in a lighthouse and weighed 2 tons . .

The team, aided by a helicopter, removed the 2-ton bulb from Bardsey lighthouse, off the North Wales coast, and took it 2 miles to the National Trust museum at Porth y Swnt, Aberdaron, where it will feature on display.

The lighthouse guides vessels in passage through St George's Channel and the Irish Sea. It was erected by Trinity House (TH) in 1821 and in 1987 converted to automatic operation, monitored from the TH Area Control Station at Holyhead; but, since 1995, it has been monitored from the TH Operations & Planning Centre, Harwich.

The removed bulb comprised 5-panel catadioptric (mirrors & lenses) optics and a 400 W metal-halide lamp. This gave a white flash 5-times every 15 seconds - visible to 26 NM.

The huge optics will, by November, be replaced by solar-powered intermittent red light from LEDs, with an interim LED array filling the role until then.

Wildlife experts state that the change will prevent thousands of migrating birds being drawn to their deaths by Bardsey’s powerful beam. But there are also fears that the island will no longer lure birds in the same vast quantities that makes it one of the wonders of the birding world - on one single night in 2003, 40,000 birds landed on the island.

Details from the links below . .

  • 05 July 2014
  • RIN

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