Customer-generators seeking to interconnect first submit a standardized "Evaluation Request" to PREPA to determine whether or not the system will qualify for the "Simple Interconnection Process." The Simple Interconnection Process applies to inverter-based systems no more than 25 kW in capacity for single-phase systems, and no more than 200 kW for three-phase systems, and which meet additional technical requirements. If the system does not qualify for the Simple Process, PREPA requires a "Supplemental Study," which will determine if improvements are required to PREPA’s electric distribution system or if changes to the DG design are needed in order to safely connect the DG. The applicant will pay for related costs.
Once approved for interconnection and after all safety tests have been conducted and certified, PREPA and the customer-generator sign a standard interconnection agreement. The regulations state that the customer-generator must also secure general liability insurance ($100,000 in coverage for systems 10 kW or less, and $1 million in coverage for systems over 10 kW) and that PREPA must be endorsed as an additional insured on the policy; however, according to PREPA, it does not require this for residential, net-metered customers. Instead, these customers must sign an agreement stating that they assume responsibility for any possible damages their systems might cause to PREPA's.
On May 27, 2014 it was decided that, the Energy Commission may require reliability studies for the interconnection of generators with a generating capacity greater than 500 kW but less than 1 MW. PREPA is required to adopt regulations for the interconnection of distributed generators with a generating capacity of less than one (1) MW, as well as regulations for the interconnection of distributed generators with a generating capacity between 1 MW and 5 MW. Regulations must take effect 180 days starting from May 27, 2014.
The rules provide specific guidance on time lines for application and review processes, as well as specific processes for dispute resolution. See the forms page on PREPA's web site for all forms and applications related to interconnection.
* PREPA, the only electric utility in Puerto Rico, is a government-owned corporation. It is governed by a board of directors that are nominated by the governor and confirmed by the state legislative assembly. The board, via resolution and after following established procedures that include a public comment period, approved PREPA's interconnection rules on July 15, 2008.