Hi Tony, low CCT seemingly comes with a price in terms of efficiency, hence the cash pressure is to install higher CCT lamps. The reduction in efficiency in moving to 3000K is said to be worth 15% or so. I haven’t studied this in detail and can’t yet confirm that % number, but it would explain the decisions being taken in this respect. Gloucestershire is the same; I’ve found out they installed 4000K as an optimum solution weighing efficiency against aesthetics.
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