GRID V OUT OF RANGE

[Hv&Lv]

That is a clever approach worth considering. Most inverters are default set for Unity. PF = 1. I think the typical spec sheets allow adjustment towards both Capacitive and Inductive.

But you are thinking that by setting it towards Capacitive or Inductive -- the Voltage would lower, while Amps stay up and keep exporting. Clever.

On the Utility Meter there would some loss but that is tolerable?

Absolutely tolerable. You aren’t charged for PF on your meter anyway.
This approach has been used to fix some clipping issues also.

 

[SteveO NE]

Inverters with these features enabled

Your utility needs to allow it though and many are behind the times. When I worked for the POCO 10 years ago I tried to implement policies to accommodate SA functions coming down the pike. Its just starting to get pushed in our area by the local ISO.

I do still point to the first comment though, this is a good reason to keep your V drops low - though the solution for pollution is dilution, its better to keep it clean on install and react to anomalies vs diluting the issue with pf correction. We also shoot for 1%, not 2%, which is usually obtained by simply using all the same size conductor (but varying # of parallel runs) for larger chunks of the system when practicable to do so - i.e. don't spec out 4 different sizes of conductors, it'll be cheaper to slighting upsize some runs for the installer to buy a larger reel that covers the whole site, and ends in less change of error when interpreting your wiring schedule.

You aren’t charged for PF on your meter anyway.

That isn't necessarily true, plenty of my customers are; however, providing leading VARs would usually help your bill if anything because you are usually penalized for lagging PF from inductive (motor) loads. Also, its not at no loss, nothing is free; however, I have noticed the next version of inverters I have seen come out this year have a higher kVA than kW output @ unity, allowing additional capacity when providing VARs to the system. For instance the new SMA is 62.5kW at unity and 66kVA when providing volt/var support.

 

[SteveO NE]

Also, its not at no loss, nothing is free;

I ran out of time to edit...I just wanted to point out free is in the eye of the beholder. With the likely Blondel Theorem meter installed each element would only record the real power, not the apparent power. You could get "free" power from the utility with poor power factor "energy efficient" devices (that have become mostly non-existent thanks to subsidized energy efficiency products that the utility companies set standards on) that take advantage of this, but from a physics standpoint, nothing is free, its just who is covering the bill that makes free relative.

 

[Phil Timmons]

Dynamic power factor and watt output reaction to voltage (and frequency) conditions is a thing you guys. See UL1741SA.

Inverters with these features enabled will throttle power factor and/or real power if voltage is too high, which in theory should keep the voltage from getting quite as high.

Any idea what that does to actual local voltages? On shared end-of-line transformers and revenue meters? What do you see for limits that the local grids will allow as deviance from Unity or 100%?