Lumens, Watts, and Volts: What's the Difference?

Watts vs. Lumens

Watt (W) is the unit of electrical energy that indicates the power consumption of a bulb. The fewer watts consumed, the less money you'll spend on energy. Wattage does NOT equal light output. Over the years, the use of incandescent bulbs has conditioned many consumers to believe that light output is equivalent to wattage: for example, that a 60W incandescent bulb needs to be replaced by another 60W bulb. Lumens measures light output: it's the quantity of light that a bulb emits. On a bulb label, lumens tells you if the selected bulb has enough light output for the intended use. The higher the lumen value, the more light a bulb emits. Historically, the most popular household consumer bulb used in the USA was 60 watt. These bulbs typically emitted 800 lumens (abbreviated "lm") of light. Thus, most consumers are accustomed to using bulbs in their home that emit 800lm of light.

What are Volts?

Voltage refers to the electrical potential difference between the wires that power a light source. Typically, the line voltage that comes into your home is 120V at the light fixture's sockets. Track lighting, undercabinet, landscape, and pendant lighting can also use low voltage lamps that operate on a transformer contained within the fixture's lighting system that brings down the line voltage into 12V or sometimes 24V. These low voltage lamps are small halogen or LED technology with small "pin-based" sockets.