solar power

Discussions regarding our FM transmitters, DX reports, antenna designs, problems...

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stylzmovement
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solar power

Post by stylzmovement »

I have added up the amperage need to power my transmiter, and my wireless laptop, I have a total of 4 amps.
How will I power this from a solar system with a car battery attach to the system. I will like to use the solar system to charge the battery for night time use; the system will run 24hrs a day ,
this is a total of 4amps per Hour .
can i get a solar system to charge the battery for about 10 hours of night time use?
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Post by pcs »

But doesn't the laptop need 19V?
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Post by stylzmovement »

i will use an inverter on the laptop
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Post by pcs »

Just calculate the total amount of Ah, ampere hours needed.

4A x24h equals ~ 100 Ah. You need to get at least that much
from the solar cells during day. Plus, since the acc
won't store all of the energy and you will loose something
due to losses. Let's say you need about 120 Ah to get
through the day 24/7.

That means solar cells must provide 10A for 12 hours (lets say that's a 12h day)
at a voltage sufficient to charge the acc, that is about 15V at least.

That's ~ 8-10 our 15W solar panels from the website and at least a 60Ah car battery :)
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Post by cliffyk »

The inverter for the laptop will be grossly inefficient, output from the solar panels will be reduced on overcast days (dependent on the amount of overcast of course)--so you'll need to have a large enough battery to get through cloudy periods and sufficient generation capacity to recover from extended periods of low output from the panels.

I'd take the numbers Marko provided and add in a 1.5 to 2.0 duty factor.
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stylzmovement
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Post by stylzmovement »

so now the big question.
when will you make a transmitter that will run on a 12 or 24 volt system.
48 volts is to many battries (4)
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Post by pcs »

Your battery will be empty in a few minutes, if you want to run a 300W transmitter.

With 50Ah car battery you may get 15 minutes time with one car battery.
Your current draw at 12V would be 40 amps. You would be loosing a lot of power
in the DC connection cables. And it would have to be heavy duty cable.

There is always a reason...
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Post by pcs »

We sold one panel and regulator immediately folowing this thread :)
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Marko - PCS Electronics
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http://www.pcs-electronics.com
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Post by cliffyk »

Cool...
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Post by stylzmovement »

so you are saying to run the system at higher voltage , we will use less amprage ?

please explain the meaning or duty cycle?
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Post by cliffyk »

Read this, then come back here and ask questions.

You'll need to garner a basic understanding of electrical and electronic engineering before the answers your are likely to receive here will mean anything to you...
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