New service built to existing non grid tied solar/generator ststem

[mooreaaryan]

I am working on bring in new residential service to a property that is currently only on “OUTBACK non grid tied system”. The customer is not allowed to backfeed grid when new service is tied in. So I decided to use a transfer switch to ensure the solar/generator never back feeds the grid. The system is quite old and the inspector said it need to be rate Utility Interactive. Since I am not connecting the existing power system to the grid why would it need to be utility interactive?
The main service panel is located at the bottom of a hill approx 250ft away. I will take the service conductors up the hill and land them on source two. Then I will take the existing power and land it on source one and the load will be an upgraded service panel 200amp.

 

[Dennis Alwon]

Are you saying you will have 2 services feeding the house? If so do you meet one of these conditions

230.2 Number of Services.
A building or other structure served shall be supplied by only one service unless permitted in 230.2(A) through (D). For the purpose of 230.40, Exception No. 2 only, underground sets of conductors, 1/0 AWG and larger, running to the same location and connected together at their supply end but not connected together at their load end shall be considered to be supplying one service.

(A) Special Conditions.

Additional services shall be permitted to supply the following:

• (1)
  Fire pumps
• (2)
  Emergency systems
• (3)
  Legally required standby systems
• (4)
  Optional standby systems
• (5)
  Parallel power production systems
• (6)
  Systems designed for connection to multiple sources of supply for the purpose of enhanced reliability

 

[mooreaaryan]

Only one service.

 

[hillbilly1]

I think what the op is saying, they have a stand alone solar system with storage, and a new utility service is being added as backup. The system is too old to meet the poco requirements to grid tie, so the op is using a transfer switch to switch to utility when the solar is low. I don’t see a problem with it, but unless they have some sort of UPS, it will not be a seamless transition. With it being non-grid tie, I see no reason for it to be utility interactive, unless the inspector is meaning using a transferswitch.

 

[mooreaaryan]

Exactly hillybilly1. Grid will only be utilized when customer is home during the summer evenings and current system can not keep up

 

[jaggedben]

The inspector is wrong.

What you are doing is just a standby generator setup. The off-grid inverter no more needs to be utility interactive than the fuel powered generators typically used in such setups.