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Two 100-watt panels temporarily "mounted" |
All of it has been with power provided by two, back-breakingly heavy, 6-volt T105 wet cell batteries wired in series and charged with two 100-watt solar panels (also wired in series) resting (but secured with wire) against the chimney on my roof. They face south and provide 40 volts at 5 amps from about 10:30am to 3:30pm local time. Decreased power is available from them during other daylight hours as the sun is at a lower angle.
A Morningstar MPPT charge controller charges the batteries more efficiently than cheaper
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Charge controller |
Wiring the arrays in series also minimizes the effect of voltage loss over the 50-foot run of 10g copper wire leading from the arrays into my shack. In parallel, my panels would produce 20 volts at 10 amps and the copper loss would amount to a 5% loss rather than the 1.25% loss of the series-wired method.
Like most modern transceivers, my Flex 6300 is designed to operate with an input of 13.8VDC. My batteries are considered fully charged at 12.74 volts and are at half capacity at 12.10 volts. This results in an RF output of 90 watts with fully charged batteries and 78 watts with the batteries half discharged (the lowest I'll ever allow them to go).
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T105 golf cart batteries |
My main reason for buying these components and operating "green" is to learn more about the practical use of solar power in order to eventually use it on an RV when camping away from commercial power. Ham radio is providing an excellent way to learn what can be expected from a given array size with a known load.
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Very nice done John, something I really want in the future. A solar powered shack, not depending on electricity from the grid. And once you get even with the money you invest in panels and batteries it is free as well as long as the sun shines. 73, Bas
ReplyDeleteHello Bas - unfortunately, solar power is not really economical. There has to be another reason besides $$$ to justify it - operating away from commercial power, operating in emergency situations (storms, etc) when no power is available at home, or just as a hobby to learn about it.
DeleteHere in Texas, I pay $00.15 for a kwh of commercial power - and we have a *lot* of sunshine for a good portion of the year. My solar set-up cost me $900. That $900 will buy 6000 kwh of electricity and it will take my solar system about 10 years to produce that amount of power. At that point, I will break even with my money if I don't spend any more. The reality is that I will need one (possibly 2) new pairs of batteries in that amount of time.
I also have a QRP solar set-up and will be posting info about it in a few days. Much more economical and even more capable than some might think...
Any RFI from the MPPT controller?
ReplyDeleteNo, none at all and I did test extensively due to many horror stories I'd heard. I bought the controller and kept all the paperwork, packaging etc with the plan being to take full advantage of Amazon's return policy if I detected any RFI. Happily, it's not an issue.
DeleteFantastic write up. Anxious to hear about the qrp setup.
ReplyDeleteThat posting will be made tomorrow - thanks for the comment.
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