Calculate kw from positve and negative energy totals

In summary, the conversation is about calculating kw or kwh from readings taken from an electricity meter that logs values every 15 minutes. The values recorded include A+ Energy Total = 3920Wh, A- Energy Total = 3480Wh, Q+ Energy Total = 3960varh, Q- Energy Total = 2920varh, S+ Energy Total = 3920Wh, and S- Energy Total = 7440Wh. The individual is trying to figure out how to get the absolute values based on the positive and negative values, and is unsure how to interpret the + and - symbols. They believe the values A, Q, and S make up the power triangle but are having trouble balancing the equation
  • #1
FusionE&I
3
0
Hi can anyone tell me if I had the following readings how could I calculate kw or kwh. The readings were taken from an electricity meter which logged the values every 15 minutes and the values below are what were recorded in the first 15 minute period;

A+ Energy Total = 3920Wh
A- Energy Total = 3480Wh

Q+ Energy Total = 248560varh
Q- Energy Total = 2920varh

S+ Energy Total = 3920Wh
S- Energy Total = 7440Wh

Really what I need to figure out is how do you get the absolute values based on the positive and negative values.
 
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  • #2
Hi just realized I posted the wrong figures. They should be;

A+ Energy Total = 3920Wh
A- Energy Total = 3480Wh

Q+ Energy Total = 3960varh
Q- Energy Total = 2920varh

S+ Energy Total = 3920Wh
S- Energy Total = 7440Wh
 
  • #3
Welcome to PF. Could you explain in a little more detail what the + and - are? AC power isn't typically expressed that way. If it's the positive and negative rms power (the area under the power curve on the positive and negative sides of the sine wave), then I would think you just add the two values together.
 
  • #4
My problem is I don't know what the + and - are.

I think as the values have h after them they are hour values, but as the values are recorded every 15 minutes I am not sure what to do with them.
Also I believe the values A,Q and S make up the power triangle but I can't get the equation to balance if you square them.

I have tried adding them and squaring them but I still can't get it to balance.

Can anyone shed any light?
 

1. How do you calculate the value of kw from positive and negative energy totals?

To calculate kw from positive and negative energy totals, you need to use the formula: kw = (positive energy total) - (negative energy total).

2. What is the significance of kw in energy calculations?

Kw, or kilowatt, is a unit of power and is commonly used in energy calculations. It represents the rate at which energy is being consumed or produced.

3. Can kw have a negative value?

Yes, kw can have a negative value if the negative energy total is greater than the positive energy total. This indicates that more energy is being consumed than being produced.

4. How does calculating kw help in understanding energy efficiency?

Calculating kw can help in understanding energy efficiency by providing a measure of how much energy is being used or produced in a given time period. A lower kw value indicates higher energy efficiency.

5. Are there any limitations to using kw in energy calculations?

Yes, there are limitations to using kw in energy calculations as it only takes into account the rate at which energy is being consumed or produced and does not consider other factors such as the type of energy source or the overall energy usage over time.

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