Step to PTO for solar

The majority of solar installations in the US are grid-tied.  This arrangement allows homeowners and commercial tenants to seamlessly pull power from their solar array, the local utility or both.  While this is all well and good, strict requirements and standards exist for connecting distributed energy resources to the existing grid.  These strict tie-in guidelines are enforced via the interconnection application process.  This process generally goes as follows; the customer submits an interconnection application prior to the installation of the system, the utility reviews the application and determines net metering eligibility.  After the system is installed the customer sends as-built documents pertaining to their system as well as electrical permits for the utility to review.  If all is in place an interconnection agreement is executed.  Following the approval, the utility will often install a special net meter and will issue the customer permission to operate (PTO).

Days for Interconnection

Although a seemingly simple protocol, a recent NREL study found the application and approval process takes an average of over 3 weeks from the time of application submittal to issuance of a PTO.  By comparison, the average installation time of a system was found to be between 2 and 4 days.  The study also found approval time increased faster than construction time as system size increased. 

To better frame this issue consider that there are roughly 500,000 solar grid interconnections today and that number is expected to swell to 1 million by the end of 2017.  To accommodate the increasing volume of applications, improvements must be made by all parties involved in the permitting process.  On the utility side more resources must be devoted to the permitting process.  To avoid having to add manpower, utilities may choose to invest in the capability to process applications online.  As of 2014, less than 20% of utilities had online applications available. 

Improvements can also be made on the side of the residential/commercial customer and the installer.  A recent survey of utilities found that the interconnection process is often hampered by customers submitting outdated forms, incomplete forms or missing required documents entirely.  Obtaining handwritten signatures can further slow the process.  Once again online applications promise to address some of these chokepoints.

Signaling a step in the right direction, reforms at the federal level have been made to address the sluggish interconnection process for larger generation facilities.  The 2013 reforms addressed the Small Generator Interconnection Procedures (SGIP) and the Small Generator Interconnection Agreement (SGIA), both of which dictate interconnections of generators under 20 MW.  Customers may now request a pre-application report from the utility to better illuminate potential snags in the interconnection approval process for the specific project site before the application is submitted.  The reforms also increased the threshold for participation in the Fast Track interconnection process from 2 to 5 MW.  Although these reforms only address facilities under FERC jurisdiction (potential for interstate electricity sales), the gears are in motion to address interconnection delays.

Published
9 years ago
Written by
Conor Walsh
Topics