You will have to ask the utility what they charge. Generally there are tariffs for such things approved by whomever regulates the utility in your state.
It's tough. I have seen a number of projects over the years suffer from last minute utility interconnection problems because the contractor normally completes the installation before the utility has done its review due to timing issues. I remember one small commercial project in particular that the utility refused to interconnect to their downtown network distribution system after it was installed. I think after 2 years of pounding on the utility the contractor eventually got the utility give PTO.
What size is your service? How would the PV system add to the load? If your 14kW system is two SMA 7.0kW SB inverters the total output at 240VAC with the 1.25X factor would be 73A, which would all go back to the utility in a worst case situation. The transformer would only have to be 14kVA to handle it, and under any other conditions the PV system would reduce the load on the transformer. Does your POCO understand how solar works?
My thoughts too. Round here, nearly all dwellings are supplied by a 25 KVA. 15 KVA is rare. 10 KVA is even more rare. What's even more rare than that, is the current that travels both ways at the same time!
What 1.25 factor? There's no 1.25 factor for current or for transformer sizing, the current is just 14000/240 = 58.3A.
For sizing inverter OCP, a 1.25X factor is applied to the maximum output current. The inverter will never produce that much current, true enough, but I was trying to look at it the way the POCO would see it as a worst case. Barring current flowing both ways simultaneously, of course.
I will just add that POCO reps who work with solar who also do not understand the fundamentals of how electricity works isn't unheard of.For sizing inverter OCP, a 1.25X factor is applied to the maximum output current. The inverter will never produce that much current, true enough, but I was trying to look at it the way the POCO would see it as a worst case. Barring current flowing both ways simultaneously, of course.
It's a good bet that someone there does though. And they are probably the ones that put in the rules.
Yes, but you didn't mention OCPD, so the 1.25x factor was out of place. I guess your point is that a confused POCO could be looking at OCPD size, rather than current.
Maybe, but maybe not. I once (more than once, actually) encountered, for example, a solar inspector who was a master electrician who labored under the misconception that the current from a PV system adds to the load on a feeder, i.e., the current flows both in both directions simultaneously. There was a feeder with a 60A breaker on the supply end and a 60A inverter OCPD on the other end. His position was that the feeder needed to have a derated ampacity of 120A.
Modern inverters produce clean sine wave output.
Yes.
'Add to the load' is probably imprecise language.
