I assume this thread was spending more energy as a typical Raspberry over a year 
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Now that is interesting
Pi4 B turned off = 0.34 W → daily 8.2 Wh
Turned off it uses 8.2 watts per day. Wonder how many watts it consumes if I throw it in the rubbish bin 
Geoff
That’s about the same as a single LED light bulb. If you’re that concerned about power consumption I suggest you stop using electricity altogether.
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Watt hours per day. “Watts per day” just shows fundamental disrespect for physical units.
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That’s about the same as a single LED light bulb. If you’re that concerned about power consumption I suggest you stop using electricity altogether.
I never expressed any concern at all, merely posed the question.
Geoff
Watt hours per day. “Watts per day” just shows fundamental disrespect for physical units.
One pays for watts consumed, I’m not sure how a device turned off consumes .34W other than having the PSU still plugged in but if that is an accurate measure then it would consume 8.16 Watts daily.
At that rate it would take 18 weeks to consume a Kilowatt or 2941 hours. I guess that is 3 kWh per year if left switched off. I can relate to 8.16 watts per day better than 3kWh per year.
Geoff
That’s not at all what i’m talking about.
Power used is a momentary value, for example: The pi is using 0.34 W. On average, this device consumes 0.34 W.
Energy used is a quantity, it adds up over time. In the last hour the pi has used 0.34 Wh. The pi uses 8.2 Watt hours per day.
Watts and Whatt hours are NOT the same.
Neither are kW and kWh.
In regards to the pi4 … it’s some mode you can get it in after shutdown if you set the correct EEPROM flags i believe. But normally it pretty much uses idle power after shutdown.
As you state, it’s best to just unplug it.
Some people would like to somehow signal the pi to turn on and do work. For them this feature could be useful, but in practice they will probably use the RPi pico to operate a transistor to turn the 5 V to the pi4 on and off.
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No, you pay for watt-hours consumed or Kilowatt hours consumed (KWH). Take a look at your electrical bill sometime.
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I am not an engineer and have only basic understanding.
But for me as consumer i pay per Wh or KWh
To my understanding:
If a device is using 2.000 Watts, it would cost me 2 KWh if i would keep it running for an hour.
Is this correct?
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Watts is rate of use of energy per second
1 Watt (W) = 1 Joule / sec
Watt-hour (Wh) is total energy used in one hour
Total energy used = rate of use of energy x time of use of energy
Hence:
1 Watt-hour = 1 Watt x 3600 sec = 3600 Joules
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Nicely explained.
Geoff
Sounds about right to me, keep it simple, all these variations of expressions serve the electric suppliers in manipulating our usage by complicating running costs.
Geoff
… is dimensional analysis no longer a thing?
(darn kids, get off my lawn!!)
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Amazing what you can derive with just dimensional analysis.
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