Projects participating in the Oregon Community Solar Program must receive approval through their electric utility to interconnect to the distribution grid. Community Solar Projects will interconnect through either Tier 2 or Tier 4 review under the processes defined in the Oregon Small Generator Interconnection Rules (OAR 860-082).
Each utility has developed a dedicated interconnection process for Community Solar projects, which is open to projects that intend to participate in the Community Solar Program and are sized to be less than the Minimum Daytime Load (MDL) (net of existing and proposed generation) of the distribution feeder to which they would interconnect. Portland General Electric and Pacific Power have established a separate queue for eligible Oregon Community Solar projects, and Idaho Power processes these projects within their general queue but tracks them separately. Community Solar projects are not required to apply through this dedicated interconnection queue and may apply through the standard interconnection queue if they prefer.
Projects that apply to their utility’s CSP-specific interconnection queue will be studied by their utility through a narrower scope than projects in the general interconnection queue. In the general interconnection queue, a utility will study a project as a network resource and will assess the necessary costs both to connect the generator to the distribution grid and to deliver the power to load. In contrast, a project applying through a utility’s CSP-specific interconnection queue will be studied as an energy resource, with the utility considering only the costs necessary to connect the generator to the electric grid.
CSP project managers should take care in identifying a project site and in proposing a size for their project, as these can dramatically impact the types of upgrades and improvements that are necessary to interconnect a project to the electric grid.
Project managers are responsible for paying the costs of any upgrades necessary to safely interconnect a project, and proper siting and sizing decisions can help to minimize these costs.
The following recommendations are provided to project managers to mitigate the risk of requiring extensive upgrades.
Regardless of size, Community Solar projects located in certain areas are likely to encounter challenges and high cost estimates in the interconnection process. It is recommended that project managers take the following into account in their initial siting decisions:
While the distribution data posted by each utility is a helpful tool in understanding the feasibility of interconnecting to a given circuit and determining the maximum project size that can apply to a utility CSP interconnection queue, there is often more complexity involved in determining how large of a project may be accommodated without requiring upgrades. It is recommended that project managers mitigate their risk by taking the following steps:
As all Community Solar projects are installed in-front of the meter (unlike Net Energy Metering projects), project managers should anticipate that their project will be required to fund a minimum basic package of interconnection improvements to allow their project to be connected to the grid and metered. In Pacific Power service area, project managers should expect to be quoted a minimum interconnection improvement cost of roughly $50,000. Project managers that plan to develop small projects should take this into account and confirm this with utility interconnection staff early in the process.
While the above guidance on siting and siting can be helpful in reducing the cost of interconnection, the impacts of each project will be assessed individually by utilities and project managers should be sure to discuss and understand all project-specific details with their utility. Utilities will convene a Scoping Meeting with the project manager and key utility interconnection staff before conducting a Tier 2 or Tier 4 interconnection study. At this early stage of the review process, project managers may have some flexibility in adjusting their proposed system design, and they should take advantage of the opportunity to discuss potential issues and alternatives with utility staff. If a project manager lacks the subject matter expertise to have an informed technical conversation at this meeting, they may wish to retain an interconnection expert to accompany them (these project managers should refer to Community Solar Development Assistance under Resources). Suggested topics to confirm with utility staff at this meeting include:
Project managers are encouraged to have conversations with both utility interconnection staff and the Community Solar Program Administrator prior to applying for interconnection to ensure they have the most up-to-date information regarding the interconnection process and are aware of any specific circumstances in their desired area. Project managers are also encouraged to request a pre-application report from their utility, which will provide prior study results and other known data for the distribution area of interest. These pre-application reports are typically available from utilities for a fee (Pacific Power charges a $300 fee for a pre-application report, for example), but non-profit or public sector organizations that are registered project managers in the Oregon Community Solar Program may request up to five pre-application reports from their utility at no cost.
The flowchart below indicates the key steps that a project manager should pursue prior to applying for interconnection with their utility, as well as factors to consider in whether to file for Tier 2 or Tier 4 review, and whether to apply to the utility’s general interconnection queue or CSP interconnection queue. Subsequent flowcharts indicate the process for obtaining Tier 2 Review, Tier 4 Review, and for completing steps that follow interconnection application approval. In developing an interconnection timeline, project managers should expect that utilities will utilize the full amount of review time allowed to them in each step. This information is provided only to provide a sense of the process to project managers, and project managers are responsible for confirming all interconnection steps, costs, requirements, and timelines with their utility.
If a project manager requests Tier 2 review, the utility will conduct a study that evaluates the project against a series of 11 screening factors that will determine whether the project is likely to have negative impacts on the grid. The utility will approve the project application if the project passes all screens, and otherwise will require the project manager to apply for Tier 4 review.
The screening factors (“Approval Criteria”) that the utility will use to evaluate the project in Tier 2 review are provided in OAR 860-082-0050 (2).
If a project manager requests Tier 4 review, the project will be studied through a series of three successive tests:
In advance of each successive study, the utility and project manager will sign a study agreement that details the scope of the study. The project manager is required to reimburse the utility for the costs of conducting the study (which will be projected in the study agreement) and must pay a deposit towards these costs prior to the utility beginning the study.
After an application is approved by the utility (either through Tier 2 or Tier 4 review), the project manager must complete a series of steps before making the project operational. The project manager must also complete certain steps within the Oregon Community Solar Program around this time. Some of the key milestones are:
This section provides guidance on potential transmission upgrades that may be identified for certain Community Solar projects. This is a developing issue, and this information will be updated as more is known about deliverability upgrade needs and the allocation of associated costs. At this time, this issue is only known to impact projects located in Pacific Power service area in Eastern and Southern Oregon. Project managers should discuss this issue in early conversations with their utility and the Community Solar Program administrator to receive up-to-date information and understand how this may impact their project.
As noted above, projects applying through a utility CSP-specific interconnection queue will be evaluated as energy resources, which will not consider upgrades required to ensure the deliverability of generated power to load. However, utilities must still ensure that power may be safely delivered to network load through the Transmission Service Request (TSR) process. This process may uncover the need for additional upgrades and costs associated with delivering the power of a CSP project to load under certain conditions. If that occurs, the utility would bring the issue to the attention of the Oregon Public Utility Commission, who would be responsible for determining how these costs would be met. As this has not yet occurred for any CSP project as of this writing, the cost responsibility for these deliverability costs is not settled.
To provide visibility into the potential need for deliverability upgrades, utilities may conduct an information-only network resource study along with the project’s Tier 2 Screening Study or Tier 4 System Impact Study. This information-only network resource report will provide project managers with an estimate of potential deliverability costs, but this report will be non-binding and project managers will not be required to pay the deliverability upgrade costs identified.
Given the uncertainty posed by these potential costs, it is recommended that project managers work with their utility to file a Transmission Service Request (TSR) as early as possible in the process so that these costs may be identified and addressed. Before filing a TSR, the utility must have approved an interconnection application and the project manager must have signed a Power Purchase Agreement (which in turn requires that the project be pre-certified by the Oregon Community Solar Program). To make this process as streamlined as possible, project managers should request pre-certification as soon as they meet program requirements and should sign a CSP PPA with the utility soon after becoming pre-certified. Project managers who have been informed by their utility that their project may trigger deliverability upgrades are also advised to delay signing any participant contracts while the issue of deliverability costs is being addressed, because of the impact that this process may have on project development.
Energy Trust of Oregon provides a limited amount of development funding to small projects and projects led by public or non-profit project managers that intend to participate in the Oregon Community Solar Program. This funding can be used for a variety of early-stage project planning activities, including funding staff time or third-party services related to interconnection. More information on this funding opportunity is available here.