30 kWh per day, while a clunky unit, is what most people would understand when talking about home consumption. It’ll be what their utility typically reports, how you’d want to size a battery, etc.
It's like you had a faucet with cross section of 2 square inches, and 15 seconds with that faucet wide open would fill a jug. That jug holds 30 squareinches-seconds of water.
You may then use that water over the course of a day. That's 30 sqin-sec per day. That is not 30 square inches for a whole day. It's second per day.
Or watt hour per week or whatever.
Yes, it can be described like 0.00034722 sqin/day, and that corresponds to no physical object and that would be largely useless.
Why not Joules or Liters? Because that's complicated for anything electrical.
"30kW per day" makes no sense. It's like saying "100km/h per day". W is a unit of power, Wh is a unit of energy.
It's unintuitive because a guy named Watt decided "Joule per second" is Watt, so the intuitive units Joule and Joule per second got turned on their head to W times hour and Watt. This is opposite to usual intuition of distance and speed for example, km and km/h. If I redefined the km/h to a "tick", then a km would become "tick times hour".
If you want a "better than nothing" but imperfect analogy, Wh is how much water you have in a bottle, and W is how quickly you can get the water out.
No, their point is wrong either way and there is no way to steel man it without saying the comment is extremely poorly articulated.
30kWh is 1.25kW for 24 hours or 30kW for one hour.
30kW every hour means 720kWh per day. 30kW all day is also 720kWh per day.
The comment is nonsense.
The only way you can steel man it is by saying he isn't concerned about the 1.25kW, he is concerned about the swings, but he said 30kW twice for two different time spans so that can't be it either.
30 kWh per day, while a clunky unit, is what most people would understand when talking about home consumption. It’ll be what their utility typically reports, how you’d want to size a battery, etc.
Sort of neither?
It's 30kW for one hour.
(Or 1.25kW for 24 hours, or however you prefer).
[Link: https://en.wikipedia.org/wiki/Kilowatt-hour]
It's like you had a faucet with cross section of 2 square inches, and 15 seconds with that faucet wide open would fill a jug. That jug holds 30 squareinches-seconds of water.
You may then use that water over the course of a day. That's 30 sqin-sec per day. That is not 30 square inches for a whole day. It's second per day.
Or watt hour per week or whatever.
Yes, it can be described like 0.00034722 sqin/day, and that corresponds to no physical object and that would be largely useless.
Why not Joules or Liters? Because that's complicated for anything electrical.
Pretty sure GP understands that, their point being you can't just wave away 'per unit time' when talking about it relative to generation, it matters.
"30kW per day" makes no sense. It's like saying "100km/h per day". W is a unit of power, Wh is a unit of energy.
It's unintuitive because a guy named Watt decided "Joule per second" is Watt, so the intuitive units Joule and Joule per second got turned on their head to W times hour and Watt. This is opposite to usual intuition of distance and speed for example, km and km/h. If I redefined the km/h to a "tick", then a km would become "tick times hour".
If you want a "better than nothing" but imperfect analogy, Wh is how much water you have in a bottle, and W is how quickly you can get the water out.
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"30kWh per day" isn't waving away anything.
30kW is a rate.
30kWh is a measure of energy, about 100MJ.
30kWh/day is a rate again, 100MJ/day.
It seems clunky, but it's a way energy usage in a house is typically measured.
Wh is a unit of energy. They're saying how much energy they consume per day.
No, their point is wrong either way and there is no way to steel man it without saying the comment is extremely poorly articulated.
30kWh is 1.25kW for 24 hours or 30kW for one hour.
30kW every hour means 720kWh per day. 30kW all day is also 720kWh per day.
The comment is nonsense.
The only way you can steel man it is by saying he isn't concerned about the 1.25kW, he is concerned about the swings, but he said 30kW twice for two different time spans so that can't be it either.