Utility Interconnection Standards

For most solar electric installations, the interconnection to the utility is the final step in the overall process. It is the point where the customer begins to realize the value of their investment and the integrator realizes full revenue recognition. However, diverse utility interconnection requirements continue to be a source of added costs for the industry. Currently, there are at least five major obstacles to lowering these costs:

• The utility interconnection paperwork is cumbersome and bureaucratic, and the forms used vary based on a variety of factors (e.g., system size);
• Each utility has its own interconnection standards, forms, and processes, which vary considerably from one to the next;
• Most utilities do not have an online submittal process for interconnections;
• There is a lack of consistent standards, processes and training options for simplicity and scalability; and
• Once the interconnection application has been approved, there is little predictability in when the actual connection to the utility will occur.

Objective

Given the significance of this step in delivering the benefits of solar power to the grid, it is imperative that there be a uniform set of interconnection standards and processes to improve predictability and reduce uncertainty for both consumers and installers.

Movement Towards Standardization

Efforts are currently underway in California and elsewhere to improve interconnection standards and processes. The Rule 21 Working Group, sponsored by the California Public Utilities Commission (CPUC) and the California Energy Commission (CEC) is one example of a collaborative effort between utilities and industry to create clear and consistent standards for generator interconnection to the distribution system grid. Other states and the U.S. Department of Energy are also studying the impacts of widespread solar deployment on the distribution system and how that might affect interconnection.

Over time, as new studies and best practices emerge, the quarterly California Solar Initiative Forums, sponsored by the CPUC, are a venue where these efforts can be brought to the attention of the industry. The Rule 21 Working Group, or a solar-focused subcommittee of it organized through SolarTech, can provide the detailed engineering and technical requirements that emerge from this process. SolarTech is committed to working with Utility Partners to evolve the Rule 21 Working Group into a vehicle that works well for both the utility and the solar industries.

Summary of Recommendations

In the short term and in light of these difficulties and costs, SolarTech proposes to undertake the following steps to work with the utilities to address these issues and to simplify the solar interconnection process:

1. Participate in the statewide California Solar Initiative Forums and Rule 21 Working Group discussions to achieve policy consensus and develop technical requirements;
2. Work with at least one investor-owned utility and at least one municipal utility (“Utility Partners”) to develop and propose a prototype process that will significantly streamline solar interconnections. Share our “SolarTech Recommended Standard Operating Procedure” for solar interconnections and encourage all utilities state-wide to adopt these standards.
3. Work with our Utility Partners to create a simplified set of interconnection forms for residential solar systems up to a reasonable size. For instance, 48kW may prove an appropriate threshold because a typical PV system using current technologies would not overload most residential service. A large proportion of residential service panels are capable of handling 200A of infeed current at 240VAC from the utility grid, and presumably they are capable of handling up to 200A of backfed current from a solar electric system. Other factors, such as transformer capacity and system protection, will also be considered.
4. Work with our Utility Partners to develop a simplified online submittal process for interconnection of all systems.
5. In light of PG&E’s recent decision to eliminate the solar disconnect from most solar installations, work with other Utility Partners to encourage industry-wide adoption of similar standards and to eliminate unique and unnecessary requirements.
6. Work with our Utility Partners to streamline the final interconnection process with the goal of continually reducing processing times to a predictable cycle time from building permit approval to grid connection via an online database statewide. This would apply equally to residential and commercial projects recognizing that each may have their own inherent requirements.