martyscholes
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Why do we still confuse KW and KWH?

Sun Aug 25, 2019 5:42 pm

I just read a thread where a poster conflated KW and KWH. That seems to be a regular mistake, despite EVs being more common than ever. What does it take to stop the confusion? The two really are a different as horsepower and a gallon of gasoline.

So that it's noted, a coulomb is a large number (some 6.24 x 10^18) of electrons. One coulomb passing through one volt of electrical potential is a joule. A joule is a (small) unit of work. One joule per second is a watt. One thousand joules per second is a kilowatt. One thousand joules per second for an hour (3600 seconds) is a kilowatt hour, which is equivalent to 3.6 megajoules. It is a shame that KW and KWH are so similar sounding and in writing, but a KW is a thousand joules per second and a KHW is 3.6 megajoules (regardless of time).

What does it take to get this right? Am I just too pedantic?

LeftieBiker
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 6:01 pm

The language is dying. Millennials and Millennial wannabes start every sentence with "So..." It is annoying when people screw up simple terms but it is only going to 'sort of get worse' rather than better. Cwerdna is ever-vigilant about energy and power terms, if that's any consolation...
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Nubo
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 7:10 pm

I long thought that adoption of EVs would bring a better awareness of electrical terms. But as time goes on I think it's going to become common for people to simply use kW when they mean kWH, and the reader/listener will be expected to resolve with context.
I noticed you're still working with polymers.

cwerdna
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 7:14 pm

martyscholes wrote:
Sun Aug 25, 2019 5:42 pm
I just read a thread where a poster conflated KW and KWH. That seems to be a regular mistake, despite EVs being more common than ever. What does it take to stop the confusion? The two really are a different as horsepower and a gallon of gasoline.
...
What does it take to get this right? Am I just too pedantic?
It drives me nuts. It happens here, on other EV boards and on various EV FB groups. No on the last question.

I usually step in to correct or to seek clarification. Unfortunately, sometimes (often ignorant) folks will attack me for it. :roll:

People got really pissed off and annoyed at the cluster#$$% I pointed to at https://mynissanleaf.com/viewtopic.php?p=564743#p564743. What's scary and surprising is what Randy pointed out at https://mynissanleaf.com/viewtopic.php?p=565245#p565245. :shock:

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Flyct
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 9:48 pm

cwerdna wrote:
Sun Aug 25, 2019 7:14 pm
martyscholes wrote:
Sun Aug 25, 2019 5:42 pm
I just read a thread where a poster conflated KW and KWH. That seems to be a regular mistake, despite EVs being more common than ever. What does it take to stop the confusion? The two really are a different as horsepower and a gallon of gasoline.
...
What does it take to get this right? Am I just too pedantic?
It drives me nuts. It happens here, on other EV boards and on various EV FB groups. No on the last question.

I usually step in to correct or to seek clarification. Unfortunately, sometimes (often ignorant) folks will attack me for it. :roll:

People got really pissed off and annoyed at the cluster#$$% I pointed to at https://mynissanleaf.com/viewtopic.php?p=564743#p564743. What's scary and surprising is what Randy pointed out at https://mynissanleaf.com/viewtopic.php?p=565245#p565245. :shock:
Your ;( overreacting. Or is it you’re overreacting? Calling folks ignorant doesn’t help.
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coulomb
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 10:26 pm

Flyct wrote:
Sun Aug 25, 2019 9:48 pm
cwerdna wrote:
Sun Aug 25, 2019 7:14 pm
martyscholes wrote:
Sun Aug 25, 2019 5:42 pm
I just read a thread where a poster conflated KW and KWH.
What? They conflated kelvin watts with kelvin watt henries? That's terrible!

Electrical energy is commonly measured in units of kWh (kilowatt hours, lower case k and lower case h). Case matters too!

It irks me that when corrected, offenders feel offended, and claim "it's just one letter, therefore it's no big deal!" Well, it is a big deal. No-one would say it's 100 miles per hour from Boston to New York, if they meant 100 miles. (I have no idea of the actual distance, and only a vague idea of what a mile is). It just gets confusing. Maybe they actually meant that there is now some mode of transport that can actually average 100 mph between these cities? Perhaps fast rail has finally come to the USA?

I really hope that this present phase of lazy typing (units, spelling, grammar) is a passing fad. Humanity is better than that.

[/pedant]

[ Edit: corrected Kelvin -> kelvin, penant -> pedant. Sigh. ]
Last edited by coulomb on Thu Aug 29, 2019 4:09 pm, edited 2 times in total.
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LeftieBiker
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 10:37 pm

Don't you mean "[/pedant]" ? ;-)
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cwerdna
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 10:43 pm

Flyct wrote:
Sun Aug 25, 2019 9:48 pm
Your ;( overreacting. Or is it you’re overreacting? Calling folks ignorant doesn’t help.
It would be you're. Well, unfortunately, that's what some of those attackers are. :(

In the case of kW vs. kWh, I don't care that much if folks get the case wrong. I let that go. I'm MUCH more concerned about using the right units.

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coulomb
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Re: Why do we still confuse KW and KWH?

Sun Aug 25, 2019 11:56 pm

cwerdna wrote:
Sun Aug 25, 2019 10:43 pm
In the case of kW vs. kWh, I don't care that much if folks get the case wrong. I let that go.
Ah. Then perhaps you have already pardoned me for my earlier gaff, the kelvin (which I used a capital K for). I did a quick search, and they all capitalized the K. Sigh. I'll go edit my shame now,
Last edited by coulomb on Mon Aug 26, 2019 3:18 am, edited 1 time in total.
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alozzy
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Re: Why do we still confuse KW and KWH?

Mon Aug 26, 2019 12:12 am

There are so many misconceptions and misunderstandings about all kinds of things, so confusion over kW vs kWh is relatively forgivable in my opinion.

I'm a lot more worried that some people still think that the earth is flat, or that there is zero gravity in space, or that the sun is actually yellow, or that science is a collection of irrefutable facts and so any "mistakes" that past scientists made, which are later refuted, somehow utterly disproves all scientific understanding and achievement (detractors of the theory of evolution love that argument).
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