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Q:
I am thinking of powering two 25 watt halogen bulbs using a lawn mower battery or possibly a motorcycle battery. I need it to remain as light as possible to keep it easily mobile. How long would one of the batteries give me light?
- Brandon (age 29)
Verona Ky
A:
It looks like typical largish motorcycle batteries store about 12 A-hr of charge, giving about 150 W-hr of energy. With two 25 W bulbs, you'll maybe get 3 hours of power, tops.
If instead you invest in 12V LED lights with the same light output as those halogen bulbs, you'll use less than 1/4 of the power, and can run at least 4 times longer with the same battery, or switch to a smaller and lighter battery. The disadvantage is the higher initial price, so it might not be worth it unless you intend to use the system a lot.
Mike W.
(published on 06/03/2012)
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