By Jason Fordney

CAISO this month launched a sweeping set of updates to its interconnection policies, an annual process made increasingly complex by a rapidly changing resource mix.

The effort “will likely address some substantial concepts but also a myriad of minor concepts that have not been addressed in some time,” the ISO said of its 2018 Interconnection Process Enhancements (IPE) initiative.

“Once we finalize the scope of the initiative, we will be able to determine the issues that will be included in this year’s process and the timing for development,” CAISO said.

The program is divided into six broad categories: deliverability; energy storage; generator interconnection agreements; interconnection cost responsibility and financial security; interconnection requests; and modifications.

A Jan. 17 issue paper defined the proposals that CAISO is considering. The document includes 42 potential topics and will be developed into a draft final proposal, but the ISO has not specified when it would be presented to the Board of Governors for approval.

The deliverability category alone contains nearly a dozen topic areas related to transmission planning, criteria for commercial viability and transparency into the availability of deliverability.

Other major tasks laid out in the IPE paper include:

• Ensuring the development of the most viable projects;
• Giving projects with power purchase agreements a greater opportunity for deliverability; and
• Providing resource developers reasonable timelines for interconnection.

The ISO expects a March ruling from FERC on last year’s more narrowly tailored IPE package, which was expedited to obtain a ruling before the next transmission plan deliverability (TPD) allocation takes place in March.

A TPD allocation provides resources the transmission capacity required to deliver power during peak conditions and is a condition of receiving full capacity deliverability status, which is critical for eligibility to be counted as resource adequacy.

CAISO twice a year allocates TPD to generating projects that meet certain criteria. The 2017 IPE package proposes a third TPD allocation, which FERC is likely to approve.

The TPD allocation process works well during periods of high procurement, CAISO said. However, renewable procurements have recently slowed significantly, resulting in few projects meeting the criteria to qualify for a TPD allocation.

There are also uncertainties around renewable procurement that will affect the ability of a resource to obtain power purchase agreements. CAISO noted that the California Public Utilities Commission has proposed establishing a two-year resource procurement cycle to meet the targets of integrated resource plans, with the first procurement proposed for the end of 2018. But modeling used by the commission for the program shows a minimal need for renewable procurement until 2026 because California utilities are on track to meet — or exceed — renewable portfolio standard targets, the ISO said.

“The IRP will have significant impacts on interconnection customer’s ability to obtain PPAs for their projects,” CAISO said.

In a Jan. 24 presentation, CAISO discussed items that stakeholders requested be included in the IPE, including a proposal that would allow interconnection customers to replace their entire project with storage during the interconnection process. But CAISO has only approved up to 10% conversion to battery from an existing project during the process.

“A complete change of technology from existing technology requires a study to determine the new electrical characteristics and the impact to the grid,” CAISO said in explaining that it would not explore that topic in IPE 2018.

The energy storage category of IPE 2018 is focused on distributed energy resources, wholly replacing existing facilities and deliverability assessment for energy storage.

The ISO is taking comment on the IPE package through Feb. 7 and said stakeholders should suggest other items that might be included.