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Comment by neya

7 days ago

20KW? Wow. That's a lot of power. Is that figure per hour?

What do you mean by "per hour"?

Watt is a measure of power, that is a rate: Joule/second, [energy/time]

> The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3.[1][2][3] It is used to quantify the rate of energy transfer.

https://en.wikipedia.org/wiki/Watt

If you run it for an hour, yes.

  • Ah yes, like those EV chargers that are rated at X kWh/hour.

    • You would hope that an EV reporting x kWh/hour considers the charge curve when charging for an hour. Then it makes sense to report that instead of the peak kW rating. But reality is that they just report the peak kW rating as the "kWh/hour" :-(

  • I asked because that's the average power consumption of an average household in the US per day. So, if that figure is per hour, that's equivalent to one household worth of power consumption per hour...which is a lot.

    • Others clarified the kW versus kWh, but to re-visit the comparison to a household:

      One household uses about 30 kWh per day.

      20 kW * 24 = 480 kWh per day for the server.

      So you're looking at one server (if parent's 20kW number is accurate - I see other sources saying even 25kW) consuming 16 households worth of energy.

      For comparison, a hair dryer uses around 1.5 kW of energy, which is just below the rating for most US home electrical circuits. This is something like 13 hair dryers going on full blast.

      3 replies →

    • Consumption of a house per day is measured in kiloWatt-hours (an amount of power like litres of water), not kiloWatts (a flow of power like 1 litre per second of water).

      1 Watt = 1 Joule per second.

      1 reply →

    • I think you are confusing KW (kilowatt) with KWH (kilowatt hour).

      A KW is a unit of power while a KWH is a unit of energy. Power is a measure of energy transferred in an amount of time, which is why you rate an electronic device’s energy usage using power; it consumes energy over time.

      In terms of paying for electricity, you care about the total energy consumed, which is why your electric bill is denominated in KWH, which is the amount of energy used if you use one kilowatt of power for one hour.

      2 replies →