[Greenbuilding] Retail Lighting Retrofit

[Paul Eldridge]

Although this falls outside the general thrust of this list, I wanted to 
share a few words about a lighting retrofit that we completed earlier 
this week.  The main retail space had been illuminated by ninety 
70-watt, 347-volt PAR30 CDM multi-head gimbals that collectively 
consumed some 7,920-watts including ballast-related overhead.  We 
retrofitted these gun slots with Philips 12-watt PAR30 LEDs using 
step-down transformers to lower fixture voltage to 120-v.  That got us 
down to 1,080-watts plus a bit more taking into account transformer losses.

To offset the corresponding lumen deficit, we added back nine 100-watt 
Philips FloatPlane linear pendants suspended directly above the floor 
displays.  With that, our net savings came to just over 5,900-watts.

What we didn't anticipate is that our top shelf light readings would 
increase from an average of 50 to 60 foot candles to between 270 and 350 
FC (2,700 to 3,500 lux).  So, in addition to the 75 per cent reduction 
in this portion of their lighting load, the improved light quality, much 
longer lamp life, and a/c related savings, we were able to increase at 
target light levels five, six and in some cases seven fold.  Needless to 
say, our client is very happy.

You can view a picture of this retrofit at: 
https://twitter.com/CollieGuy902/status/715299261689249792/photo/1 
(click on the image to expand).