Test Results of Incandescent and Compact Fluorescent Lights

2006 Test Results of Six CF Bulbs

Here is a spreadsheet showing the results of tests of one incandescent and six compact fluorescent light bulbs. This testing was done on November 16, 2006.

Summary of Results:

The worst CF put out only 1.62 times as much light per watt as an incandescent.
The best CF put out 2.51 times as much light per watt as an incandescent.

These tests did not consider power factor, so the CFs probably use less actual energy than indicated. (One watt does not actually equal one volt-amp if you consider PF, but the actual difference is difficult to determine.)

The universal research disclaimer applies: Further testing is needed to clarify and validate these results :-)

Bulb #	I or CF?	Marked Watts	Marked Lumens	Measured Volts	Measured Amps	Measured Volt-Amps	Measured Light (fc)	Watts Exaggeration Factor	Measured Light / Volt-Amp	Light Eff WRT Incand
1	I	150		118	1.184	139.712	30	93%	0.21	100%
2	CF	15	725	118	0.212	25.016	10.2	167%	0.41	190%
3	CF	27		118	0.431	50.858	17.7	188%	0.35	162%
4	CF	26	1700	118	0.341	40.238	21.7	155%	0.54	251%
5	CF	15	810	118	0.193	22.774	9.3	152%	0.41	190%
6	CF	13		118	0.175	20.65	10.1	159%	0.49	228%
7	CF	23		118	0.32	37.76	19.1	164%	0.51	236%

Notes

1 is GE Canada soft white, 150 watt at 120 volts
2 is Sylvania soft white dulux EL globe, never used, 15 minute burn-in period
3 is Commercial Electric SKU 738-704 Model ES-27, showing signs of previous use, marked 0.450A. WORST
4 is GE soft white 100, package of 6 has barcode 043168477093, never used, marked 390 mA, 15 min burn-in. BEST
5 is Panasonic 150, marked 0.22A, found in utility tunnel and probably never used. No burn-in period.
6 is Bright Effects, marked 210 mA, previously used
7 is Harmony Lighting, marked 390 mA, previously used. SECOND BEST

Light = fc measured 36" from bulb, which is 24" in front of a light wall
"Watts Exaggeration Factor" = measured volt-amps / marked watts
"Measured Light per Volt-Amp" = measured light / measured volt-amps
Light Eff With Respect To Incand = measured light / volt-amp divided by same for the incandescent tested

Home