LED domestic lighting

[Ian Stirling]

Basically all sorts of reasonable amounts of white light apart from filliment and Carbon Arc are about the same efficiancy, 100-130 lumens/watt. The lumen is a measure of how bright it appears. LPS (the yellow ones) are about 180 lumens/watt, or a fair bit more light.

However, the light can be such that it's not as good as white light for determining details.

It would not surprise me if for certain tasks (determining if coloured objects placed in the road are to be avoided, or run over, not to mention CCTV) the dimmer white light is better. There is also the possibility that the white fixture may be better designed.

It only takes some 30% of the light going in non-useful directions to make the yellow lights less bright.

[Mike]

message

Nah, 'lectric usually.

[brugnospamsia]

Those are most likely Metal Halide - much better colour rendition but much less efficient and shorter lived than Low Pressure Sodium (yellow). High Pressure Sodium (pinkish) is intermediate in terms of colour rendering, efficiency and longevity.

I recently noticed that some streets in the slightly dodgier part of my town have High Pressure Sodiums instead of the more usual LPS, as does the nearby section of the cyclepath ....