Energy savers/large rechargable batteries for lighting

jeff f said:

dankness, my dad once told me not to argue with an idiot....because in short time, nobody can tell the difference. i would like to see mr tree hugger peddle enough energy to grow a single blade of grass let alone real grass. and i want to hear about all mr treehuggers wonderful energy saving ideas in the works to save the planet...even though NOT A SINGLE hihgly educated electrical engineer worldwide has been able to figure out. lets hear about your "projects"........silence? thought so

jeff

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jeff f said:

dankness, my dad once told me not to argue with an idiot....because in short time, nobody can tell the difference. i would like to see mr tree hugger peddle enough energy to grow a single blade of grass let alone real grass. and i want to hear about all mr treehuggers wonderful energy saving ideas in the works to save the planet...even though NOT A SINGLE hihgly educated electrical engineer worldwide has been able to figure out. lets hear about your "projects"........silence? thought so

jeff

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cleef said:

Mac, I like where your head is at. I'm just exploring your idea so please don't think I'm being critical.

Just because the inverter is rated at 7000 watts doesn't mean it requires that much to operate or that your car is capable of producing that. It will only draw enough current to power whatever you have plugged into it, and if you exceed the power that the alternator is producing, it will just draw off the battery. That is assuming that you have it wire directly to your battery. If it's plugged in to your cigarette lighter you'll be limited to the 15 amps or whatever fuse you have in there. In fact, your car is definitely not capable of producing 7000 watts. Let me explain.

My car, a civic, has a 55 amp alternator. 55 amps at 12 volts = 660 watts. Now you can change the voltage which will change the amperage and you can invert from DC to AC, but the wattage will not increase because the inverter doesn't produce more power, it just inverts the power that your alternator supplies to it. You also pay a tax with any of these conversions because none of them are 100% efficient.

Admittedly, I have a small car so I looked up a Chevy Silverado and they have alternators in the 150 amp range. Even with a 150 amp alternator at 12 volts you're only making 1800 watts.

For more reference, I looked up generators. Consider this. A DeWalt 7000 watt generator has a 13 horsepower engine. Do you think you can produce 13 horsepower? I know I can't.

And all of these alternator output ratings are at 3,000 RPM. Remember that your car alternator runs on a belt that spins it twice as fast as your engine. 100 RPM's is a pretty reasonable cadence, so you're going to need to gear the thing at 30:1 to get the alternator spinning at 3000 RPM's. With that gearing, it's going to be quite hard to pedal. I think you might be seriously underestimating how hard it would be to spin the thing at 3000 RPM for an hour. That might even be beyond Lance Armstrong hard.

But I still think you should try it. At least it's some green energy. See what you can do and how much power you can get out of it.

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gotot said:

is there anyway to capture static( from a tv or the pressure change in the air) into a battery?

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TheDankness said:

Static electricity, regardless of the fact that its high voltage, will support almost no flow of current. This is the reason you don't die when someone shocks you, the voltage is high enough, but it only lasts a millisecond and the current is probably somewhere in the micro amps.

The point? Even though the voltage is high in static electricity, because there is so little flow of current you are really looking at almost no power in watts. Maybe even less than a watt of power there, idk. Not a bad idea though, that's forward thinking.

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cleef said:

Mac, I like where your head is at. I'm just exploring your idea so please don't think I'm being critical.

Just because the inverter is rated at 7000 watts doesn't mean it requires that much to operate or that your car is capable of producing that. It will only draw enough current to power whatever you have plugged into it, and if you exceed the power that the alternator is producing, it will just draw off the battery. That is assuming that you have it wire directly to your battery. If it's plugged in to your cigarette lighter you'll be limited to the 15 amps or whatever fuse you have in there. In fact, your car is definitely not capable of producing 7000 watts. Let me explain.

My car, a civic, has a 55 amp alternator. 55 amps at 12 volts = 660 watts. Now you can change the voltage which will change the amperage and you can invert from DC to AC, but the wattage will not increase because the inverter doesn't produce more power, it just inverts the power that your alternator supplies to it. You also pay a tax with any of these conversions because none of them are 100% efficient.

Admittedly, I have a small car so I looked up a Chevy Silverado and they have alternators in the 150 amp range. Even with a 150 amp alternator at 12 volts you're only making 1800 watts.

For more reference, I looked up generators. Consider this. A DeWalt 7000 watt generator has a 13 horsepower engine. Do you think you can produce 13 horsepower? I know I can't.

And all of these alternator output ratings are at 3,000 RPM. Remember that your car alternator runs on a belt that spins it twice as fast as your engine. 100 RPM's is a pretty reasonable cadence, so you're going to need to gear the thing at 30:1 to get the alternator spinning at 3000 RPM's. With that gearing, it's going to be quite hard to pedal. I think you might be seriously underestimating how hard it would be to spin the thing at 3000 RPM for an hour. That might even be beyond Lance Armstrong hard.

But I still think you should try it. At least it's some green energy. See what you can do and how much power you can get out of it.

Click to expand...

macdadyabc said:

thank you very much for the info, and not bashing my idea. I know that the alternater would have to be going around 3,000 rpm to make enough charge, so ITS NOT IMPOSSIBLE. The only limiting factor on this idea is the human element, because yes, it would be extremely hard to pedal that fast on an unmodified gear bike. I know i can build a machine with gears and long levers for lots of leverage and have it put out 3,000 rpm. I have built, fixed, and restored alot of different engines from cars, boats, and motorcyles and taught myself to weld, construct, and basically everything i know about creating. If i can draw a blueprint of my idea in my notebook, then i can build it. I dont pay attention to the useless stuff in highschool( about 80% useless shit i will never need to think about in my life ever), but instead, i like to learn hands on stuff and life skills . + rep for being nice.

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TheDankness said:

Static electricity, regardless of the fact that its high voltage, will support almost no flow of current. This is the reason you don't die when someone shocks you, the voltage is high enough, but it only lasts a millisecond and the current is probably somewhere in the micro amps.

The point? Even though the voltage is high in static electricity, because there is so little flow of current you are really looking at almost no power in watts. Maybe even less than a watt of power there, idk. Not a bad idea though, that's forward thinking.

Click to expand...

macdadyabc said:

so 0 watts is not a bad idea, but 200 watts is inneficient and not forward thinking? wtf? hypocrite

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