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Cykablast3r t1_irw3jy8 wrote

What's the use case here?

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Allmightydohllah t1_irw5lxd wrote

One could power your doorbell or a traffic sensor so imagine several of these and as they get more efficient they can power more

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BinniesPurp t1_irxs6t8 wrote

Not 290milliwatts but 290 microwatts

A doorbell would need 20-30 of them which would be the size of a room lol

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markatlnk t1_iryp8n1 wrote

As someone that teaches EE, 290 uW is more than enough to run a door bell. I have have microprocessor designs that have been running 21+ years on a single CR2477 battery with a 1 amp hour capacity. That is only taking 16 uW. You use a capacitor to store energy and use just a bit when someone pushes the door bell.

These units are based on an MSP430 processor with a 915Mhz transmitter. They do sleep 99.9x% of the time. Wake up every second for 50uS and once every 10 minutes for 0.25S when they need to transmit.

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BinniesPurp t1_ish2uu9 wrote

Sorry, to clarify I ment the speaker, not the sensor / button lol

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Cykablast3r t1_irw6kus wrote

Could both of those things not easily be connected to the grid? Seems like this would just add complexity where it isn't needed.

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CompteDeMonteChristo t1_irw8y25 wrote

It seems to be really small energy. To me it is specifically for case where it is remote and changing battery is painful. A bit like a small solar panel.

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5kyl3r t1_irwj7br wrote

not true, 290 microwatts is useless. 15x20cm isn't even small. a 15x20cm solar panel would be able to do around 6 watts. (assuming 20% efficiency cells). an equivalent area solar panel would be 20,000x more powerful. which is why this is article is pointless

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