Luminaire efficacy
According to BRE’s The essential guide to retail lighting:
A luminaire is a ‘Light fixture or fitting; an electrical device used to create artificial light and / or illumination, by use of an electric lamp.’
Luminaire efficacy is the ‘Light output of an entire luminaire divided by the total power consumed by the lamps and ballasts. Equal to the lamp efficacy multiplied by the light output ratio of the luminaire.’
It is expressed in lumens per Watt (lm/W).
Ballast or control gear, is ‘Part of the control equipment of fluorescent or discharge lamps, used to stabilise the current. The older, traditional main-frequency ballast can consume up to 20-25% of the total lamp current. A modern electronic ballast working at high frequency consumes about 30% less current, and can be used to regulate or dim the lamp output.’
[edit] Related articles on Designing Buildings Wiki
- Ballast or control gear.
- Colour appearance.
- Colour Rendering Index CRI.
- Daylight benefits in healthcare buildings.
- Daylight factor.
- Daylight lighting systems.
- Dichroic reflector.
- Discharge lamp.
- Extra-low voltage lamps.
- General lighting v task lighting.
- Illuminance.
- Lamp.
- Lamp efficacy.
- Lighting.
- Lighting energy numeric indicator LENI.
- Lighting of construction sites.
- Luminaire.
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
ECA's reflections on Party Conference season
Burnham wants to be confident of winning before asking for a fresh mandate.
New Chief Construction and Scientific Adviser
Sergio Cavalaro, Professor of Infrastructure Systems at Loughborough University.
Building safety levy for England
CIAT publish estimator tool for members.
Water sector faces a growing crisis that could slow the delivery of vital infrastructure.
Undervaluing our industrial past
Heritage value changes as taste for building styles changes.
Changing expectations around competence and compliance
New information sheet from CIAT.
Grenfell investigation files passed to CPS
Angela Rayner apologises on behalf of the British state.
Electrical contractors need to understand the practical implications.
The real barrier to getting more value from digital technology.
Your guide to The Construction Reset at UKCW Birmingham.
Accommodating the Victorian and Edwardian working woman. Book review.
Rethinking passive fire protection in design
PFP demands the same level of design rigour as structure or services.