- Lamp
- Component of luminaire which emits light, e.g. from a
discharge or incandescent filament. Commonly known as
a 'bulb' or tube'. See a
comparison chart;
and a discussion of
startup energy requirements of fluorescent
- Latent heat
- Heat absorbed or released, without any change in temperature, during a change of
phase to or from vapour, liquid or solid (see also sensible heat)
- League table
- Method of presenting lists ranked by best, worst, biggest, etc.. Needs to be used
with caution when applied to energy performance because small measurement errors can precipitate
wild changes in rankings of closely-grouped results. The term is sometimes used in energy
management software to denote a list of users ranked merely by size, which is not very illuminating.
When applied to the cost of deviations from expected consumption, however, one obtains the
overspend league table which acts as a prioritised
and filtered exception report.
- LED
- Light emitting diode; a semiconductor light source.
- Lighting
- Not always significant in terms of expenditure, but extremely
important from a psychological standpoint. Click
here for
tips on saving lighting energy and
here for
a comparison of lamp technologies.
- LPG
- Liquefied Petroleum Gas, for example propane or butane.
- Luminaire
- The fitting comprising reflector, lens or diffuser, and control gear, etc
and lamp
- Lux
- Unit of illumination intensity (light flux per unit area)
- LV
- Low-voltage. Commonly held to signify voltages less than 440V
although in some contexts indicating 12V as distinct from mains voltage
|
Light meter
|