Community Renewable Energy

Interconnection steps >100kW

Step 1: Submit Interconnection Request to Transmission Provider

It is extremely important to start discussions with your utility—or utilities, if wheeling is an option—very early in the wind development process. Interconnection costs can be the limiting factor in a project, so it is best to find out early on how much the expense will be. Interconnection request forms are available at each utility’s Web site. A fee may be required along with submission of the request. Below is a list of information necessary to complete an interconnection request.

• Facility location
• Generating purpose (What will the energy be used for? i.e. used on site, sold to others, etc.)
• Local electric service provider (if different from Transmission Provider)
• Energy source and conversion technology
• Type of generator and specifications
• Generator manufacturer, model name, number, and version number
• Generator nameplate rating in summer and winter in kW and kVA
• Maximum physical export capability requested (equal to the total kilowatts the facility could produce)
• Components of facility that are certified and who certified them
• Individual generator power factor
• Total number of generators to be interconnected
• Power systems load flow data sheet
• One-line diagram of facility
• Transformer specifications
  

While the amount of information requested may be daunting, it is best to submit your request as soon as possible to allow the utility to set up a project file. Design changes are frowned upon by financial backers, but may be necessary to accommodate the requirements of the utility as well as the needs of the project.

Step 2: Scoping Meeting with Utility

“The purpose of the scoping meeting is to discuss the Interconnection Request and review existing studies relevant to the Interconnection Request. The Parties shall further discuss whether the Transmission Provider should perform a feasibility study or proceed directly to a system impact study, or a facilities study, or an interconnection agreement.” (FERC, 2005)

The scoping meeting should include qualified technical team members to assess the relative ease with which the proposed energy facility can interconnect with the utility. Given the information provided on the interconnect request form and information provided by the utility on the transmission and distribution system close to the project site, engineers from the utility and project team will recommend next steps. If there is agreement that there will be no adverse impacts on the transmission and/or distribution system, then the team may move on to a system impact study. If the team believes that there may be adverse impacts, then a feasibility study will be required to identify the problem areas and decide if an interconnection at the proposed site is possible.

Step 3: Feasibility Study

The feasibility study will determine if additional facilities are necessary for the proposed project to interconnect to the utility. When possible, the utility will use previously developed studies to examine the impact of the proposed project, but they may, in some cases, need to perform a new study. The cost of this new study would be the responsibility of the customer. The study would seek to determine the potential for circuit breaker faults and thermal overloads or voltage limit violations that would result from the interconnection. It would also provide an initial review of grounding requirements and electric system protection. If required, the study would describe facilities needed for the interconnection and a cost estimate for those facilities. If the feasibility study shows no adverse impacts, the utility may provide an interconnection agreement without further study. Otherwise, a System Impact Study will be required.

Step 4: System Impact Study

“A system impact study shall identify and detail the electric system impacts that would result if the proposed Small Generating Facility were interconnected without project modifications or electric system modifications, focusing on the adverse system impacts identified in the feasibility study, or to study potential impacts, including but not limited to those identified in the scoping meeting. A system impact study shall evaluate the impact of the proposed interconnection on the reliability of the electric system.” (FERC, 2005)

At the end of the System Impact Study, the customer and transmission provider should have an accurate read on the facility changes needed to accommodate the interconnection. With this knowledge, a Facilities Study will be started.

Step 5: Facilities Study

The Facilities Study is the last step before an Interconnection Agreement is finalized between the utility and the project developer. In the Facilities Study, the utility lays out exactly what needs to be done to interconnect to its system, the equipment necessary to complete the interconnection, and the associated costs, including construction costs. The design of the required facilities and upgrades may be done by the utility or their contractors. Alternatively, the utility and the customer can come to an agreement wherein the customer’s contractors design the facilities and upgrades, which are then approved by the utility. This approach could be useful if the utility does not have significant experience with community renewable energy projects.

Step 6: Interconnection Agreement

Once the facility upgrades and their associated costs have been agreed upon, the utility will write an executable interconnection agreement. Along with the facility upgrade costs, this agreement may include O&M fees payable to the utility for the upkeep of the facilities. O&M fees are often paid annually and calculated as a percentage of the actual installed cost of the interconnection facilities. These fees can be substantial and should be accounted for in the project’s financial plan. With these fees agreed upon and the document signed, the “customer” can begin construction of the project with a guarantee that the utility will allow the interconnection of the energy facility to its grid. This agreement should not be confused with the Power Purchase Agreement, which is dealt with separately during the financing phase.