According to the Department of Energy: replacing incandescent light bulbs with CFL or LEDs could potentially save between 100 to 190 terawatt-hours (tWh) annually. Just converting a home's lighting can do your finance and the environment good.

Incandescent Lights

Incandescent lights have been around since the days of Edison. They have done their job, but waste 85% to 90% of their energy consumed as heat. Incandescent lights have a Service life of 1,200 hours.

NOTE: Governments around the world have passed measures to prohibit the sale of incandescent light bulbs for general lighting. The aim is to encourage use of more energy-efficient lighting alternatives, such as compact fluorescent lamp (CFLs) and LED lamps. Brazil and Venezuela started to phase them out in 2005, and the European Union, Switzerland, and Australia started to phase them out in 2009. Likewise, other nations are planning scheduled phase-outs: Argentina, Russia, and Canada in 2012, and Malaysia in 2014.

Compact Fluorescent Lights (CFL)

CFLs have been available for the past few years. Their prices have dropped dramatically making them a great affordable conservation choice. CFLs consume 75% less energy than incandescent lights with a Service life of 10,000 hours. They contain mercury... bummer.

Light Emitting Diodes (LEDs)

Light Emitting Diodes (LEDs) are the next generation of efficient lighting with impressive reductions in electricity bills and environmental impact. LEDs consume 90% less energy than incandescent lights with a Service life of 50,000 hours. They contain no mercury... terrific!

The first available LEDs now out produce around 40 lumens per watt (less than CFL) and are expensive. The good new is that LED's of 80 lumens are coming making them better than CFL. CREE R&D have set the record to over 200 lumens! That's running a 60 Watt equivalent at around 4 Watts!


A lumen (lu) is a measure of the total amount of light output. Lumens per watt (LPW) is light produced for each watt of energy they use.

Divide a light's lumens by the number of watts it uses. For example, a 100-watt light bulb usually has around 1,500 lumens, so the LPW is about 15.

NOTE: Higher lumens means more light. Shop for lights that produce the most light (lu) using the least Watts (energy).

Below are lights with a 60 Watt 900 lumen incandescent equivalent rating. Notice how Watts goes down as Lumen Per Watt goes up.

Lighting Watts lu LPW Comments
Incandescent 60 900 15.0 Waste 85% of its energy to heat
Compact Fluorescent(CFL) 14.2 900 63.3 Currently available and affordable
Light Emitting Diode (LED) 22.5 900 40.0 Currently available, but currently expensive
Light Emitting Diode (LED) 11.3 900 80.0 Newer version... now available
Light Emitting Diode (LED) 4.3 900 208.0 CREE R&D Sets a new record... WOW!

Organic Light Emitting Diodes (OLEDs)

OLEDs will change how think and use lighting. The are highly energy efficient and is environmentally friendly. There will be entirely new lighting applications developed with effects that we can now only imagine. They should appear sometime in 2013.

They emit light from the surface and can be made flexible/rollable, and even transparent like a window or reflective like a mirror. They are thin, rugged, lightweight, and have fast switch-on times, wide operating temperatures, no noise and environmentally friendly.