[net.consumers] More Lightbulb Information!

wasser_1@viking.DEC (John A. Wasser) (02/15/85)

	Here is some lightbulb trivia gathered from the labels of
	G.E. 120V lightbulbs at some local stores (Price is based 
	on the lower non-sale price from two stores):

	G.E.		Rated	Average	Average	
	Bulb		Input	Output	Life	Price
	Type		Watts	Lumens	Hours	Dollars
	----------	------	------	------	------
	Standard	100	1750	 750	$0.85
	Standard	 75	1190	 750	$0.85
	Standard	 60	 870	1000	$0.85
	Standard	 40	 505	1000	$0.85
	Soft White	100	1710	 750	$0.75
	Soft White	 75	1170	 750	$0.75
	Soft White	 60	 855	1000	$0.75
	Soft White	 40	 490	1000	$0.75
	Miser		 95	1710	 750	$0.95
	Miser		 70	1170	 750	$0.95
	Miser		 55	 855	1000	$0.95
	Long Life	100	1585	1500	$1.50
	Long Life	 75	1075	1500	$1.50
	Long Life	 60	 820	1500	$1.50
	Clear Bulb	100	1750	 750	$1.15
	Clear Bulb	 60	 870	1000	$1.35
	----------	------	------	------	------

From these figures, I checked a number of "figures of merit".  Here are
the top five bulbs in each class: 

	(Note: Cost of Screwing was ignored.  Electrical costs are figured 
	at $0.06 per KWH.  The total electricity cost over the life of 
	the bulb was generally around four times the price of the bulb)

Power Efficiency (Lumens per Watt):
	(Use these if your electrical power is much greater then $.06/KWH )
	Miser 95, Standard 100, Clear 100, Soft White 100, Miser 70

Cost/Light Efficiency (LumenHours per Dollar):
	(Use these if you want the most light for your dollar)
	Miser 95, Standard 100, Soft White 100, Clear 100, Long Life 100

Cost/Bulb Efficiency (Hours per Dollar):
	(Use these if you just want ANY amount of light no matter how dim)
	Soft White 40, Standard 40, Miser 55, Soft White 60, Standard 60

Conclusion:  If you are a landlord who is providing light for somebody
	else, use low wattage bulbs because they provide the most bulb
	life for the dollar.  If you want illumination, use high power 
	bulbs because that are more power efficient and will cost less
	FOR THE SAME AMOUNT OF LIGHT.  If you don't like to change
	lightbulbs (Cost of Screwing is high) choose the Long Life bulb
	in the appropriate wattage range... you loose little power 
	efficiency for the additional life.

		-John A. Wasser

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