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im working on a project to light up an area of what two (maybe but doubt 3) 500 watt worklights will light. will the power inverter with two or three outlets, power that with a 12volt car battery with like 1320 watts. and if so for how long?
- oakley (age 20)
That car battery won't last very long powering standard incandescent lights. A standard car battery might have about 800 W-h of energy. It sounds like you'll get maybe a half-hour or so trying to power those incandescents with a battery through an inverter.
Switching to fluorescent bulbs would gain you about a factor of 4 in operating time.
I think your best bet is to switch to LED's. You can get ones powered directly by the battery, avoiding the energy loss and inconvenience of the inverter. The best LED's are even more efficient than fluorescents. They're also well-suited to operating outdoors, and should be the longest-lasting type. The one drawback is high initial cost, but it sounds like for your application they might still be the best bet. You could get enough light for maybe 2.5 hours from one battery charge.
(published on 12/21/2011)
Follow-Up #1: low-budget lighting
so i checked into LEDs, rechargeable ones which would provide complete convinence, that product reviews say aren't near as bright and most other LED technology seems to be in colors n such. So my question now is what would you suggest i do when i dont have hundreds to spend on the good LEDs. Would multiple 12v batterys(they are cheap im seeing them online for 10 to 40 dollars) with however many watts i listed earlier work to light 2 to 3 halogen worklights for 2.5 hours, or should i go for the 2 to 3 180 LEDs (comparable to a 500 watt worklight). and Since you suggested them could you by chance know of a source of such lights preferably online for better pricing. im trying to film with these lights at night and in past experience with a generator two or three lights work. But due to prices a generator is out of the question, cops are quick to run us off so speed of setting up is key(portable battery would work very well, and we are all broke, halogen worklights are in all of our garages, LEDs arent. Any of your help could save our season.
- oakley (age 20)
park city, utah, usa
So this does sound too low-budget for LED's, at least for a couple years until their price drops enough. I don't know of any ultra-cheap sources.
For batteries, I believe your best combination of price/energy/convenience is standard car batteries, thanks to their being competitive mass-market products.
For lights, if you want something easy and sturdy, you can just use halogen car headlights directly with the 12V batteries. However, as incandescents they're still several times less efficient than fluorescents. You could run much longer with fluorescents powered through an inverter. Consumer Reports has ratings (with approximate prices) of LED and CFL bulbs designed for use with line power. Usually you can get CR in a public library. The big drawback of CFL floodlights for what sounds like (literally) a fly-by-night operation is that they're a bit slow to reach full power. So you've got a tradeoff between needing more batteries for car lamps or needing an inverter and having a bit of delay on the lighting.
When you guys are done, please send us a link to your work.
(published on 12/25/11)
Follow-up on this answer.