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Is it possible to tell what is pulled from the grid in kwh/d? 

The power feed shows the negatives in the graph but for example the grid kwh/d reading shows a negative number if the pv generation is higher, this doesnt help as you have to do mental arithmetic to work out the difference between pv & grid.

Is there a simple way to only include the positives in the kwh/d numbers so the negatives are not included.

I might not make sense, if so let me know and I will post a video !

Dave

You need to look at the arithmetic available in emoncms - click the spanner on the Inputs page and there you'll see in the drop-down in the Process column all the available operators. "Allow positive" is one of the ones you need, and "+ input" or "- input". Not knowing what is what in your feeds means I can't be any more specific. You might need to get a bit inventive here.

Hi Robert,

The Feed 'power' is the CT clamp log to feed.

When the PV is generating it goes negative so the kwh/d is not true of what I pull from the grid.

I have attached a couple of screen shots.

dod,

Your total consumption is simply the difference between your PV generation and your line connected reading. So, in your case your total consumption would be PV1+ PV2 + Load, or TotalPV + Load. If you look at the middle of the day, you are generating a peak power of about 2400 W, and your load was about -2200 W at that time, so your consumption is the sum of those two (2400 W + (-2200 W)) = 200 W. At night, your PV will simply be zero, and your line value will not have any export, so your consumption will be simply your load (0 W + 100 W or so = 100 W). You can do that math in your input processing and then log to kwh and kwh/d fairly easily.

Dan

Hi Dan,

I have updated my inputs to hopefully cover it, thanks for the pointers, it makes sense when you get your head around it.

http://emoncms.org/dodegkr

Dave