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Snowman9000's avatar
Snowman9000
Explorer
Jan 20, 2016

Flat solar panel performance today in Quartzsite

300 watts flat on the roof. Clean, no shadows on panels, 65F. 12v system. Today in Quartzsite, what's a reasonable expectation of amps in BULK charging, at 1 PM? I was only seeing 11.x amps at jus...
CA_Traveler's avatar
CA_Traveler
Explorer III
Jan 22, 2016
red31 wrote:
~11, flat panel irraradiance in tuson got to ~700 today
https://www.nrel.gov/midc/ua_oasis/display/

300 watts / 18v yields 16.6A panels
16.6 * 700/1000 = 11.6A
This implies that MPPT would yield:

300W / 14 = 21.4A * 700/1000 = 15A * 95 percent controller/wiring efficiency = 14.3A

And there we go - proof that MPPT yields 23 percent more amps than PWM. :B

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