What happens to excess electricity produced in each case?

quique

Case 1

Office has 1 main service panel that feeds 2 subpanels, 1 for each floor.

If I put an 11kw inverter into the 1st floor subpanel and that subpanel only pulls 5kw, then those extra 6kw are lost or do they "travel" up to the main service panel and down to subpanel #2 if being pulled by IT?

Obviously it's preferable to feed those 11kw into the main which can properly feed each subpanel.

Case 2

If the bldg has 3-phase power and 1 main service panel which is 480/277 which feeds other subpanels via a transformer and that subpanel is 240/277 and we feed 11kw to a subpanel, that extra 6kw doesn't "travel" back up to the main, does it?

Cariboocoot

Re: What happens to excess electricity produced in each case?

GTI's produce current at Voltage. If there is no demand for the current, no current is produced. The grid connection is a constant current demand as far as a GTI is concerned. Beyond that it has no way of knowing what wires it is connected to: any wiring in parallel to the GTI is capable of receiving its output. This includes wiring form sub-panels to the main panel and from the main panel to the grid. There isn't anything that will block AC power from flowing in both directions.

quique

Re: What happens to excess electricity produced in each case?

But in the case where the subpanel is at one voltage and the main service panel is at a different one?

BB.

Re: What happens to excess electricity produced in each case?

Think if in terms of total Watt / KWatts...

The meter is doing the judging. It does not care if 10 amps at 120 VAC or 5 amps at 240 VAC... it is all 1,200 Watts/1.2 kWatts.

If you have 2.4 kWatts from the GTI inverter on the 240 VAC line and your microwave is pulling 1.5 kWatts on one of the 120 VAC lines, the meter will credit you with 900 watts/0.9 kWatts of generation.

For all intents the Utility Grid is providing the "useful power". The GTI just "recharges" the grid (turns the meter backwards) or at least slows the meter down going forward (if local loads exceed the present GTI output).

-Bill