Recent content by e350_ambo_camper

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    Physicist answering solar related questions

    From a paper written by Victron's CTO (https://www.victronenergy.com/upload/documents/White-paper-Which-solar-charge-controller-PWM-or-MPPT.pdf) PWM & MPPT are with in 5% of each other under typical use conditions. not included is the controller power consumption which can be 7-10W/100W.
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    Physicist answering solar related questions

    Panels don't have to reach 100C; charging performance suffers when the panel voltage drops to 15 Volts. Panel/cell temperatures often reach 70C even in mild conditions. After all, the cells are designed to absorb as much sunlight as possible, but convert less than 20% in to electricity. Add...
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    Physicist answering solar related questions

    emtmark is correct. China has flooded the market with inexpensive mono-crystalline panels, driving the price down. Amorphous panel makers now target niche markets where size, weight, portability is important and have priced their products accordingly. Several large scale a-Si panel makers for...
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    Physicist answering solar related questions

    There's really no upper limit to PWM's advantage for flat-mounted rooftop systems. Under these conditions, the panels tend to run hot and MPPT's theoretical edge is lost. Some connect panels in series under the mistaken belief that boosting the input voltage somehow recovers the temperature...
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    Physicist answering solar related questions

    simple explanation - amorphous silicon (a-Si) cells lack the orderly crystal structure mono-crystalline (c-Si) cells. This lack of order makes the photon -> electron conversion process less efficient; also inefficient is the process of collecting those electrons. However, a-Si cells can be...
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    Physicist answering solar related questions

    My standard response for this PWM vs MPPT question is: If you're chasing the Sun (camping in relatively warmer areas during the winter), PWM ~MPPT. If you're chasing snow (Aspen, CO in Jan), MPPT >> PWM. Most people don't have true appreciation of how panel/cell temperature affects the...
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    Physicist answering solar related questions

    Absolutely! if this is what you have under the hood -
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    Physicist answering solar related questions

    Hello All, I am a physicist with 25+ years experience in PV, energy storage, thermal & related fields. I am also the owner of Bogart Engineering. I am happy to answer any questions on these topics as they relate to off-grid, boondocking & related topics. I will not make specific product...
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