Thanks to another recent landmark ruling by FERC, speeding up the interconnection queue is not only a climate imperative but a federal requirement.

Complying with that rule, called FERC Order 2023, is what led the California Independent System Operator (CAISO) to restructure its interconnection process using GridUnity’s tools. The FERC rule mandates a sprawling range of interconnection reforms, and last month CAISO announced that FERC had approved the reforms it proposed to bring itself into compliance with the order.

CAISO and GridUnity were then able to move from launch to completion of their software deployment in about five months, Fitzsimons said.

The new system is a big and welcome change from how CAISO has historically managed its interconnection process, said Deb Le Vine, the grid operator’s director of infrastructure contracts and management.

California’s boom in clean energy has placed an enormous workload on CAISO. In its most recent window for applications, developers applied for 541 energy projects to interconnect to CAISO’s grid, she said. That’s more than double the 204 projects in the previous ​“cluster” — so called because, instead of studying projects individually, they’re ​“all being studied at once,” she explained.

Back in 2009, when CAISO first moved from the old ​“serial” study method to a cluster method, ​“all of it was done with paper,” Le Vine said. ​“We used to take this huge conference room,” fill it with documents, ​“and we’d have people working around the clock because we had to review them in 10 days.”

CAISO now requires electronic energy-project applications, she said. But until it started using GridUnity software, those applications still had to be manually validated, with CAISO staff poring over each one to double-check the details.

GridUnity’s approach of standardizing all data inputs and analysis from application to review stage simplified that task, she said.

“What ends up happening with the interconnection process — and this is so cool — is that there are validations already built in,” she said. ​“If the number can’t be greater than 500 kV [kilovolts] for the size of the transmission line, but someone accidentally puts in 5,000, it rejects it automatically — whereas we used to have to comb through the data to find the error.”

The company’s automation also helps with the next key part of the process, Fitzsimons said — doing the power-flow modeling that determines how all of the hundreds of new projects being considered for interconnection will impact the broader CAISO grid. Grid operators and transmission-owning utilities use power-flow modeling software platforms such as Siemens’ PSS®E, GE’s Steady State Power Flow, and PowerGEM’s TARA to ensure the grid can operate safely and reliably.

“Historically, when these transmission owners and ISOs were preparing to do the modeling and simulation, the gathering of the data into the base model was 35 to 45 percent of the time spent,” he said.

Now, GridUnity automatically pushes data from every pre-vetted application into these modeling platforms. It also automatically updates those models every time a project is added to or drops out of the queue — a relatively common occurrence as applicants fail to secure the land rights, permits, or other prerequisites for moving forward.

“That cuts a huge amount of time out of the process,” Fitzsimons said, given how complicated it can be for ISO and utility engineers to constantly track and check the status of hundreds of would-be projects. ​“When someone drops out, they’re dropping out through our software — so we know how the cluster is being winnowed down, and we know the new set of data that needs to be injected into the base model.”

That leads to the next tricky multi-party exchange that needs careful tracking, Le Vine said — assessing what grid upgrades are needed to allow projects to be interconnected, and then fairly assigning the costs of those upgrades to the projects spurring them.

This is called cost allocation, and it’s one of the thorniest and most litigated parts of the interconnection process, since the upgrade costs assigned to projects can make or break their economic viability.

It’s also a process driven by the utilities that own the transmission systems under the authority of the ISO, which means that all three parties — utilities, ISOs, and project developers — have to stay up-to-date with each other’s data.

“Typically it takes two to three weeks to pull the facility data out, the system impact data out, the costing data, anything that needs to be negotiated” between the parties, Le Vine said. Any changes to the roster of projects in that cost-allocation calculation can force the parties involved to start all over.

Trying to keep all of that ever-changing information straight via email threads and phone calls can be a nightmare, Fitzsimons said. In the worst case, it can lead to costly mistakes, such as the dispute between wind-project developer Tenaska and grid operator SPP over a $69 million reassessment of grid-upgrade costs that ended up taking three years of regulatory and legal challenges at FERC and in federal court to resolve.

But with the GridUnity system, CAISO and California’s major utilities have a shared store of data to work from, Le Vine said. ​“What is the power flow? What network upgrades have to be built for this project? What position is it in at a substation, or do they have to build a new substation?”

In the past, utilities have had to spend more than a month ​“to pull the data out of the different databases and fill out the report,” she said. ​“But now the data is all in one database — you push a button and out comes a report.”

The end goal of all this work is to secure a generator interconnection agreement — the approval to connect to the grid that allows a project to begin construction. GridUnity can continue to share data between project developers, utilities, and ISOs as they track progress on that front, Fitzsimons said.

That helps ISOs and utilities know if the projects they’re relying on to meet their grid capacity and reliability needs are on track or not — a big concern for grid operators that need to make sure projects are on schedule to meet growing power demand years into the future.

CAISO is eager to track the improvements that its GridUnity-enabled interconnection process yields for its latest interconnection cluster, which opened in October and closes at the beginning of December, Le Vine said.

“That’s just the tip of the iceberg, where we’re learning how much time we saved in some of the automatic validation pieces that were previously done manually,” she said.