ggunn-
I meant Sunny Island and SI, of course.
But what about the Tripowers? Don't they do the same, so if there was some kind of frequency problem in the grid (or xfmrs), it would affect the inverters?
Smart$
Someone would have to run the numbers, but I can't fathom a double step down scenario as being more efficient than a single transformer step down scenario.
For instance-
If the POCO was going to provide a standard 12470V to 480/277 transformer(s) that were 96% efficiency, but instead the customer bought a 4160V to 480/277 that was 98.75% and then the POCO's was 4160 to....7200V?
If not 7200V, 12.47KV....but if that POCO one happened to be 97.5% due to....some reason, the 98.75% and 97.5% together would be better than a single 96%, wouldn't they?
Here's another question- if the PV output is much more than the load, and the PV is outputting power 54% of the time (annually), it's really only pushing out to the grid say 40% of the time, because there's a variable load (which can even exceed PV output in late afternoon at times).
BUT- the PV is also putting out (annually) 3x the annual load.
Which is more important- the fact that the xfmrs are running towards the load (step down) 60% of the time OR the fact that there is 30,000kWh going to any loads and 60,000kWh going OUT thru the xfmrs (step-up).
It has to be the latter, so you'd therefore want to design any xfmrs as step UP?
Current doesn't get lost. Charge is conserved, so you have Kirchhoff's law.
Would it? I thought the inverters are able to efficiently adjust their voltage output to match the grid for small deviations like 203 versus 208. It would mean a little more current for the same power, so the I^2R losses would increase slightly, but that's it.
That's the first I've heard of Kirchoff. I think it may depend on the inverter model/company?
All I was really thinking was that (fault) current might sneak by the meter thru neutral somehow.
But besides that....if the grid side voltage was high, the inverters would adjust and put out less current?