Unusual spikes in energy use

[Danwilliams.mg@gmail.com]

I have a customer who has a Ted 5002-g installed and is monitoring solar produ tion on MTU2 and whole house usage on MTU1. We have the TED setup correctly and it has been providing readings throughout the fall and winter. The issue we have run into is unusual spikes in power up to 50 kW followed immediatley by an equal -50 kW reading. Another time the reading was 25 and -25 kW. Can this be attributed to a power spike, even though the voltage was reasonable at the time (243 v)? Or do you think there is a glitch?


0   3/3/11 3:49:00 PM   -0   0   242.6
0   3/3/11 3:48:00 PM   -0   0   242.6
0   3/3/11 3:47:00 PM   -0   -0.02   242.8
0   3/3/11 3:46:00 PM   -50   -4.92   242.8
0   3/3/11 3:45:00 PM   50   4.93   242.7
0   3/3/11 3:44:00 PM   -0   0   242.6
0   3/3/11 3:43:00 PM   0   0.01   242.3
0   3/3/11 3:42:00 PM   0   0.02   242

And........

0   3/1/11 9:57:00 PM   0   0.03   242.9
0   3/1/11 9:56:00 PM   0   0.03   242.9
0   3/1/11 9:55:00 PM   1   0.07   242.7
0   3/1/11 9:54:00 PM   1   0.07   242.7
0   3/1/11 9:53:00 PM   -25   -2.43   243.2
0   3/1/11 9:52:00 PM   -25   -2.43   243.2
0   3/1/11 9:51:00 PM   25   2.48   243.3
0   3/1/11 9:50:00 PM   25   2.48   243.3
0   3/1/11 9:49:00 PM   1   0.06   242.8
0   3/1/11 9:48:00 PM   1   0.06   242.8
0   3/1/11 9:47:00 PM   0   0.04   242.8
0   3/1/11 9:46:00 PM   0   0.04   242.8
0   3/1/11 9:45:00 PM   0   0.04   242.7
0   3/1/11 9:44:00 PM   0   0.04   242.7
0   3/1/11 9:43:00 PM   1   0.06   242.6
0   3/1/11 9:42:00 PM   1   0.08   242.4

Any help and/or insight would be appreciated.

Thank you.

[Certified Solar]

Is this spike in the generation? If it is, this occurs during cloudy weather, and are spikes in the actual generation, not a monitoring anomoly. The theory (I don't know if it has been proven, but is the accepted explation) is that the clouds act as reflectors as they approach the sun, increasing the sun hitting the panels, then the reduce it as they pass in front of the sun. This creates a spike followed by trough.

I know it seems like an outlandish explanation, I myself wouldn't believe it except that I heard it from Bill Brookes and have seen the phenomenon in several different systems, only on cloudy days.

[pfletch101]

Is this spike in the generation? If it is, this occurs during cloudy weather, and are spikes in the actual generation, not a monitoring anomoly. The theory (I don't know if it has been proven, but is the accepted explation) is that the clouds act as reflectors as they approach the sun, increasing the sun hitting the panels, then the reduce it as they pass in front of the sun. This creates a spike followed by trough.

I know it seems like an outlandish explanation, I myself wouldn't believe it except that I heard it from Bill Brookes and have seen the phenomenon in several different systems, only on cloudy days.

You do see small spikes in solar production on partly cloudy daya, but I believe that your explanation is incorrect. Solars panels are quite sensitive to (their own) temperature, producing significantly less power at higher temperatures. On a sunny day, they reach a temperature that is substantially higher than ambient, and consequently  produce much less power than they would if they were cooler. On a partly cloudy day, when shaded, they cool down; then, if the sun suddenly reappears from behind a cloud, the (now) cool panels transiently produce more power. In my experience this produces a 10-20% spike over steady-state levels - not tens of kW. You need to look elsewhere for the cause of these spikes (and I see them, too).

[Danwilliams.mg@gmail.com]

I appreciate your responses, notice the time of day for the + 50 kW and -50kW spike was in the afternoon, and then the second spike of +25kW and -25 kW was at after 9 pm at night so no solar production at that point. We are looking at a factor of ten so that is well beyond the Voc and Isc of the panels and not possible with the solar system, and most likely not possible from the 200amp main panel at 240volts.

If you take 240 volts x 200 amps you get 48kW, close to the 50 kW but then what accounts for the -50kW number certainky not the solar and that is the only generating option they have. Again these readings are from the main MTU 1.

More ideas are welcome, thanks for reading.

[Certified Solar]

Oh WOW. I hadn't paid that close of attention to the numbers. That is true, you would not see spikes like that due to clouds, 10-20% average production has been my experience as well.

I would say it is most likely a malfunctioning unit, though some other thoughts that are really just shots in the dark. Loose connections in the system such as at the weather-head and the main panel lugs (assumption is intermittent arcing)...Do lights flicker when a large load such as a refrigerator kicks on? Or maybe some other source of induction current...maybe an MTU installed in the inverter housing (I just installed one like this and am crossing my fingers that it doesn't cause some weird problem like this, so far it has worked like a charm, but then again it went in only a week ago). Oh one other, that is more plausible, is there a home automation system or some other equipment that uses a line frequency?

[pfletch101]

I would say it is most likely a malfunctioning unit, though some other thoughts that are really just shots in the dark. Loose connections in the system such as at the weather-head and the main panel lugs (assumption is intermittent arcing)...Do lights flicker when a large load such as a refrigerator kicks on? Or maybe some other source of induction current...maybe an MTU installed in the inverter housing (I just installed one like this and am crossing my fingers that it doesn't cause some weird problem like this, so far it has worked like a charm, but then again it went in only a week ago). Oh one other, that is more plausible, is there a home automation system or some other equipment that uses a line frequency?

As I noted, I see spikes of this sort too - typically once or twice a day on two or three days a week, but I may go a number of days without seeing one. Interestingly, too, I only see them on the channel that monitors my solar feed. I think that they represent false values rather than indications of real electrical events, particularly since they are reflected in the relevant minute and hour totals but appear not to affect the daily totals for the solar channel.

[techniplex]

My unit is doing the same thing an I do not have any power generating sources. Just monitoring incoming power. Just upgraded to 1.0.406 from 1.0.383. Ran fine for 4 months, but now it is pretty much useless as my projected bill is $8,837,715.87 which is up from 228.36 the previous month. The new version of footprints seems to be missing some icons on the web page.

http://192.168.75.41/images/buttons/neton.gif
http://192.168.75.41/images/buttons/mtu1off.gif
http://192.168.75.41/images/buttons/mtu2off.gif
http://192.168.75.41/images/buttons/marker.gif
http://192.168.75.41/images/buttons/hneton.gif
http://192.168.75.41/images/buttons/hmtu1off.gif
http://192.168.75.41/images/buttons/hmtu2off.gif

[Mr Cool]

Reset the MTU, Gateway and Router. 
That got rid of my spikes, and it is now reporting accurate information to the google power meter.

Good Luck.

[TEDSupport6]

Make sure you have the latest release of our firmware. Instructions and files at this link: http://www.theenergydetective.com/ted-5000/firmware-upgrade.

If your Footprints is not displaying correctly after doing the update (i.e., missing buttons), verify that your firmware versions have indeed been updated (Help > About) and then clear your browser's history.