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I am trying to battery power a 40 or 60 watt household incandescent bulb with alkaline batteries. How many will I need? It is important that the whole set up is as light as possible as it will be suspended in a cloth/bamboo chandelier.
- kelly bordonada (age 47)
This sounds quite hard. You'd need about 80 1.5V alkaline batteries in series to light the bulb normally. That's fairly expensive and bulky. Worse, they would run down quickly. Your 60 W bulb draws about 1/2 Amp of current. You'd probably want C batteries so that they could supply enough current without running down very rapidly. They might last around 10 hours.
In order to keep things light, you'd be better off with some new LED bulbs. They're expensive, but they use less than 1/4 the power of the incandescents. That lower power consumption will end up saving you money because you'll use fewer batteries. You can get LED bulbs designed for use with 12 V supplies, and power them from a pair of 6V alkaline lantern batteries, or from 8 1.5V batteries. You might want to use D batteries since the current draw would be high for AA's. The 8 D's would last around 10 hours.
The point is that 8 D's are a lot lighter and cheaper than 80 C's.
(published on 05/07/12)
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