How to convert electric bill kWH to kVA?

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GoldDigger

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You have not showed us how to calculate the demand via the kWH.

Please share your knowledge with the rest of us and post the the steps to do this.
He has not claimed an ability to *calculste* it. He is claiming an ability to *estimate* it based on some characterization of the type of customer involved.
He is correct that an estimate (NSWAG = Non Scientific Wildly Assumed Guess) can be obtained, but I would respond that the estimate is essentially useless for any real user.

Edit: I added a few letters to NSWAG definition.:)
Derek
 
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Haji

Banned
Location
India
You have not showed us how to calculate the demand via the kWH.

Please share your knowledge with the rest of us and post the the steps to do this.
Well, suppose the OP's building is residential. The typical load factor for such a building is 0.42 per EPRI report. Suppose the average demand as worked out from the utility bill is 20 KW. Then from the equation for load factor, Maximum demand=20/0.42= 47.62 KW. This is an estimate for the maximum demand for the OP.


He is correct that an estimate (NSWAG = Non Scientific Wildly Assumed Guess) can be obtained, but I would respond that the estimate is essentially useless for any real user.

Such an estimate may be useful to the OP, in the absence of accurate data, for energy saving planning.
 

GoldDigger

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Well, suppose the OP's building is residential. The typical load factor for such a building is 0.42 per EPRI report. Suppose the average demand as worked out from the utility bill is 20 KW. Then from the equation for load factor, Maximum demand=20/0.42= 47.62 KW. This is an estimate for the maximum demand for the OP.




Such an estimate may be useful to the OP, in the absence of accurate data, for energy saving planning.
What the table shows is a mean value for each listed usage. Without a corresponding standard deviation figure you have no way of knowing the extent to which you can depend on that estimate.
For example for residential there can be as much as a factor of two difference in the load factor just based on whether there is someone home during the day or not.
 

iwire

Moderator
Staff member
Location
Massachusetts
He has not claimed an ability to *calculste* it. He is claiming an ability to *estimate* it based on some characterization of the type of customer involved.
He is correct that an estimate (NSWAG = Non Scientific Wildly Assumed Guess) can be obtained, but I would respond that the estimate is essentially useless for any real user.

Edit: I added a few letters to NSWAG definition.:)
Derek

Of course it can be estimated. :roll:

But I see the OP asking for 'the demand' not an estimate of demand and that cannot be provided from the kWh.
 

iwire

Moderator
Staff member
Location
Massachusetts
Well, suppose the OP's building is residential. The typical load factor for such a building is 0.42 per EPRI report. Suppose the average demand as worked out from the utility bill is 20 KW. Then from the equation for load factor, Maximum demand=20/0.42= 47.62 KW. This is an estimate for the maximum demand for the OP.

That is right, it is an estimate, likely a meaningless one at that.

The NEC requires we know the demand, not an estimate of demand.
 

Smart $

Esteemed Member
Location
Ohio
...The NEC requires we know the demand, not an estimate of demand.
That's what it all boils down to...

NEC compliant demand value. Either it is or it is not... and if you have to calculate it (and I don't mean convert), it is not.
 

Smart $

Esteemed Member
Location
Ohio
But what the OP wants? An estimate or an exact value of maximum demand KW?
For NEC compliance with 220.87 is the only reason I can think of that anyone would even want it on this forum... but yes, it is possible there is some other reason. :angel:
 

Haji

Banned
Location
India
For NEC compliance with 220.87 is the only reason I can think of that anyone would even want it on this forum... but yes, it is possible there is some other reason. :angel:

Yes. NEC has nothing to do with energy conservation and in fact encourages wastage of energy. Doesn't it?

Such an estimate of maximum demand may be useful to the OP, in the absence of accurate data, for energy saving planning.
 

kwired

Electron manager
Location
NE Nebraska
Does peak demand mean much when it comes to energy conservation topics? Isn't the overall goal with such topics to reduce overall energy consumption?

If one were trying to save $$ on the energy bill because of high peak demand charges - you would have to have metering that tells you those peak demands before they can determine to bill you those peak demands in the first place. Running same load at different time still uses same energy though.

Outside of demand charges from POCO's, about all peak demand means to most of us is how large must a person size the source, conductors, gear, etc. that is used to power that load.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Consulting Electrical Engineer - Photovoltaic Systems
Well, suppose the OP's building is residential. The typical load factor for such a building is 0.42 per EPRI report. Suppose the average demand as worked out from the utility bill is 20 KW. Then from the equation for load factor, Maximum demand=20/0.42= 47.62 KW. This is an estimate for the maximum demand for the OP.




Such an estimate may be useful to the OP, in the absence of accurate data, for energy saving planning.
In case you haven't noticed, the OP ran screaming from the room a while back. :D
 

BackInBlack

Member
Location
Las Vegas, NV
It did become a big room but no, I did not run screaming but you did confirm what I was thinking which is it can't be done with what I have. NEC high demand cannot be calculated from total energy used in a month.

Thanks to all for sharing, I am looking for NEC demand load, the building is commercial and the owner provide copies of the utility bill except it was only the front page which shows the kWH used per bill cycle. The building was once multi-tenant but know it is all occupied by same tenant using (4) meters. The owner wants to know if the existing service has capacity for another meter, he had been told he has maxed out the other (4).

So now I'll get the high demand from the utility co. it just takes longer to get.
 

Haji

Banned
Location
India
NEC 220.87 clearly shows how to calculate maximum demand for existing installations. But the OP still asked how to convert electric bill KWH to KVA. That led to the above discussion.
Shall we continue the discussion or not?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Yes. NEC has nothing to do with energy conservation and in fact encourages wastage of energy. Doesn't it?
I don't see how energy conservation has anything to do with the subject of this thread.

While the NEC is very conservative with the required load calculations that does not encourage wasting of energy.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
...
Shall we continue the discussion or not?
The original discussion was over a long time ago, because despite your assertions to the contrary, the OP cannot accomplish what he said he wanted. The extension of this discussion consists mainly of you asserting your beliefs, and now your bias against our code, then others countering your points in an attempt to make you understand. This makes it absolutely pointless to continue. You are entitled to your opinion, but I vote for closing this thread to avoid further sanctimony.
 

Besoeker

Senior Member
Location
UK
The original discussion was over a long time ago, because despite your assertions to the contrary, the OP cannot accomplish what he said he wanted. The extension of this discussion consists mainly of you asserting your beliefs, and now your bias against our code, then others countering your points in an attempt to make you understand. This makes it absolutely pointless to continue. You are entitled to your opinion, but I vote for closing this thread to avoid further sanctimony.
I'm surprised that it is still going given that was a direct an succinct answer in post #7.
 

Haji

Banned
Location
India
I don't see how energy conservation has anything to do with the subject of this thread.
Of course, there is no direct connection of the energy conservation concept with the thread. It is only an 'in case the OP implies it' point.
While the NEC is very conservative with the required load calculations that does not encourage wasting of energy.
Well, what it means when NEC does not make voltage drop limits along the conductors mandatory (which ensures limiting energy loss) but just an option, for example?:)
 

Haji

Banned
Location
India
The original discussion was over a long time ago,

Yes. You are correct: The original discussion was over a long time ago.
I, with other forum members, am exploring the implications of the OP's first post.

The extension of this discussion consists mainly of you asserting your beliefs, and now your bias against our code, then others countering your points in an attempt to make you understand.

Why not it be the way around?:)

''The extension of this discussion consists mainly of others asserting their beliefs, and now their bias against the code, then I am countering their points in an attempt to make them understand.''

Because, for example, as regards demand and estimate of demand, NEC takes into account the latter by 'demand factor' for installations other than existing ones.
 
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