I read Lance's recent ReNew 114 article on retrofitting LEDs to a T5 fluoro fitting. I liked the way that aluminium square section was used to both replace the tube and provide a heatsink for the lights. I've got quite a number of T5 fluoro lights, some of which would work well with this treatment (mostly Nelson T slim-line interior).
Replacing T5 fluoros with LED isn't a great efficiency improvement since T5 gets about 90 lm/W. Compact fluoro such as PLC get closer to 60lm/W, so replacing them is better proposition. I've got a number of wall sconce lights using PLC tubes. I keep changing my plans for how to retrofit them, but my current idea is to replace the PLC tube and socket with an aluminium square tube about 150mm long and 40mm square, and to mount 2 LEDs pointing up, two pointing out, and two pointing down. If I run these at 2W each, I'll get about 12W, which should give similar light output to the current 18W CFL. The best part about the change would be instant turn on, instead of the blinkity blink of PLC with internal starters. I've got a box of spare CFL tubes, so I won't be making this change any time soon.
Lance used a mixture of warm white and daylight colour LEDs to approximate cool white colour. This reminded me a commercial LED floodlight for the video industry. This was a small unit about 100-150mm square, with a mix of warm white and probably daylight white LEDs. An adjusting knob allowed you to fade from one colour LED to the other. The likely use was as an infill light (e.g. to light up the otherwise shaded side of a face), with the colour adjustment being used to match the existing lighting on the subject.
Lance's use of LED ribbon may also be relevant to another retrofit. I have pelmets over the windows, with a recess in the top holding 6 T5 28W fluoros (168W total). I want to put 30-50W of LED lights in the pelmet to provide suitable lighting for watching TV, or walking around rather than into furniture. My thought was to put one Cree XPG LEDper metre, because LED ribbon was too expensive. With ebay prices, it might be possible to put up about 25m of LED ribbon to create a uniform soft lighting in the room. Alternatively, separate LEDs may produce a more interesting light pattern on the wall. Ebay listings unfortunately seem to omit some of all of the specifications of beam width, lumen output, power consumed, and colour temperature.
Any other ideas on how to retrofit LEDs, or make a custom LED fitting?
