Most of us believe that compact fluorescent light bulbs save electricity. As I looked for further ways to save electricity in our apartment (having exhausted all the obvious suggestions) I noticed that there were a number of non-standard size bulbs (twelve to be exact - "the dirty dozen") that had not been replaced.
We have two articles on this - Dirty Dozen arrested by Missouri Highway Patrol - explaining the types of bulbs we needed, and Incandescent vs. CFL - Electricity Analysis showing the actual electricity use for each set of light bulbs over a two day period.
The graph compares the electricity used for the two sets of light bulbs, each set being turned on in the same sequence, with 15 seconds between each light being turned on. Please see the notes at the end of this article for information on using CFL's in a bathroom, and our plan to replace them with LED's
X Axis - 15 second time intervals
Y Axis - Watts
Although I expected a savings, the results are quite dramatic when visualized. If it were not for the bathroom fan, which did not change, the new lights would have been saving more than 75% of the electricity of the old.
I do suggest you look at the right hand side of this graph and compare it to that of the left.
There is no trickery and the axis are the same. This is what a 75% electricity saving for a regular two bedroom apartment looks like when you replace the old incandescent bulbs, with the latest technology CFL bulbs.
I encourage you to look at our forum on Home Energy Lighting where we have articles on the history of CFL's, how to select a CFL - particularly regarding CFL disposal, Mercury, Light intensity, Light color and Buzzing.
Update: October 2010 - I have noticed that the T2 A19 CFL's, with frosted glass cover (looking like a regular bulb) do take a few minutes to reach the full 800 Lumens.
Update: November 2010 - I need to qualify my earlier thoughts. In most cases waiting for the CFL light bulb to reach its full intensity is not an issue. This is not working out for our bathroom - the delay is an issue!
Update: December 2011 - We have persevered, the bulbs are still working but the delay is getting longer as the bulbs age. They will soon be replaced - I hope to try LED's - stand by!
Update: March 2012 - We are working with LED Lighting Gallery to test the use of their A19 - 9W LED light bulbs - for our bathroom. We hope to reduce the energy footprint a further 35%, end the issue of waiting for the bulbs to reach full light intensity, and enjoy 11 years of useful life!
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