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In Wasteful Earth Hour?, it's claimed that candles emit roughly 10 times the carbon dioxide of light bulbs of the same brightness. While emissions will vary depending on the candle, the lightbulb and the electricity source, is this claim more or less correct?

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Does an LED count as a light bulb? There should be LEDs that are the same brightness as some candles. – Paul Apr 1 '12 at 3:36
I would have assumed locally-made beeswax candles are close to carbon-neutral. – Oddthinking Apr 1 '12 at 4:54
Are we talking life-cycle production, transport to market, purchase, use, disposal; or just while it is lit? There's ambiguity in the question as well -- The question says "use emit" and needs editing. – Paul Apr 1 '12 at 5:04
@Oddthinking for some reason I forgot about that aspect (that you're burning something that was grown recently, not fossil fuel). – Andrew Grimm Apr 1 '12 at 5:05
@rdhs: First sentence: agreed (hence comment, not answer). My comment was more showing there is no single answer here. Second sentence: There are wax-degrading microorganisms, but I love the idea of beeswax-sequestration to save the atmosphere. Quick, let's file a patent. – Oddthinking Apr 1 '12 at 5:31
up vote 5 down vote accepted

Although I do not agree with the statement here is a link that explains mathematically how some people got to this particular ratio.

The writer takes into account the carbon dioxide emitted by a candle and the carbon dioxide that is emitted by the electricity that powers a light bulb with the same luminosity.

In my opinion the calculation is not complete since it leaves out the energy needed to manufacture a light bulb. We should make comparisons taking into account the overall carbon dioxide footprint.

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Hi and welcome to Skeptics! Can you summarize the author's calculations and sources to prevent link rot? – Sam I Am Apr 1 '12 at 14:02
@Dhakthan: you don't need anything--- good answer. But I don't think this is good to include energy of manufacture. This is a way of putting a non-carbon neutral label on clearly carbon neutral things, and is just a maneuver people to label things like "nuclear power" net carbon positive. – Ron Maimon Apr 1 '12 at 14:14
@SamIAm, the explanation of the calculations is rather long and this would make a very huge post. Furthermore I am not sure that I can incorporate math equations in my post :) The resume is that one candle emits 10.69 g of CO2 per hour while the per candle-equivalent of electric light per hour is only 1.11. – Dhakhan Apr 1 '12 at 14:43
I agree to some point regarding the misuse of that kind of arguments. On the other hand, to reach any conclusions we have to take into account the overall "energy cost" of the procedure and not confine to an arbitrary calculation of only a part of this procedure. – Dhakhan Apr 1 '12 at 14:53
Off-topic discussion of policy deleted. If you wish to discuss it further, there's a place for it. – Oddthinking Apr 5 '12 at 4:12

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