Assertion: sodium lamp | /r/HasProperty | efficient
Facets:
value: quite
type: DEGREE
Source sentences:
text: High-pressure sodium lamps are quite efficient — about 100 lumens per watt, when measured for photopic lighting conditions.
text: Low-pressure sodium lamps are very efficient, up to 180 lumens/W, although the light is a monochromatic yellow
text: High-pressure sodium lamps are quite efficient — about 100 lumens per watt, when measured for photopic lighting conditions.