I have some electric power readings collected from a smart meter. With each reading there is energy consumed as shown in figure at link.

Some readings do not have energy values. So, I need to calculate these values manually in order to complete the data set. How should I calculate these missing values given the fact:

1. The time interval between successive readings is 30 seconds

I used the formula energy(watt-hour)= power(in watts) * time(in hours), but it is not giving correct values on applying on the readings associated with energy values. How should I calculate the energy values? Is there any other approach to calculate energy values?

My calculations: Considering second reading given in figure:

Energy= power * time  //(formula)
= 123.4582443 * 30
= 123.4582443 * 0.00833  //(time in hours)
= 1.028 watt- hour
but, correct value  is 1670763.75

• The math works here. What are you doing to get it wrong? Sep 12 '15 at 10:03
• @IgnacioVazquez-Abrams, Sorry. Now, I have shown my calculations. Sep 12 '15 at 10:15
• Have you noticed a trend in the Wh values? Sep 12 '15 at 10:18
• Yes, there is a trend. I think this is because the time difference is too small (30 seconds) Sep 12 '15 at 10:25
• The point that @IgnacioVazquez-Abrams is failing to make is that the "Energy" values are cumulative. The difference between the first and second readings matches the value you calculated for the second line. Sep 12 '15 at 10:31 