solar panel generates more energy than needed

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garberw
 
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solar panel generates more energy than needed

Post by garberw »

Specs: my project uses about 600 mA at 5V max I expect. It is a raspberry pi zero 2 W and an ADC and some lower current breakouts. If I have a 6V 9W colossal solar panel and a bq24074 breakout and a 6600mAh battery what happens to the excess energy received by the panel after the battery is fully charged and the cpu is at peak? It is designed to go a week with no sunlight.

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adafruit_support_bill
 
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Re: solar panel generates more energy than needed

Post by adafruit_support_bill »

The bq24074 has a load-sharing circuit. When the charge cycle is complete, current will stop flowing to the battery. The bq24074 will draw enough to power the chip and the power-good indicator LED. And it will route power from the panel to the load so the load can draw what it needs.

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garberw
 
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Re: solar panel generates more energy than needed

Post by garberw »

thank you

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sj_remington
 
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Re: solar panel generates more energy than needed

Post by sj_remington »

what happens to the excess energy received by the panel
It is discarded as heat.

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garberw
 
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Re: solar panel generates more energy than needed

Post by garberw »

Do you mean heat in the solar panel or heat in the bq24074?

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sj_remington
 
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Re: solar panel generates more energy than needed

Post by sj_remington »

Both.

Think about what happens when you put a solar panel in the sun, but don't connect it to anything.

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