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Lumens and Watts


Lumens are being introduced as the new unit of measurement for light bulbs. In the past, the strength of light bulbs was measured in watts, which is actually a measure of power. This isn’t a useful unit of measurement for new energy-saving light bulbs, which consume much less power than old-style incandescent light bulbs. So because comparisons based on wattage are no longer meaningful, the strength of new energy-saving light bulbs is expressed in lumens, which measures instead the amount of light they produce. The higher the number of lumens, the brighter the light. If you haven’t already, you’ll soon start seeing light bulbs categorised by lumens rather than wattage. There isn’t necessarily a correlation between lumens and watts because they measure different things. But as a rough guide, look for:

Comparisons of  basic watts to lumens in general