The Challenge
At 11 a.m., a developer racing to submit a 250 MW battery energy storage system (BESS) project in Alberta called E Source for help. The deadline for AESO's Cluster 3 was midnight, just thirteen hours away. Equipment selections were still incomplete, and the preliminary single-line diagram needed significant clarification. The technical application work required to submit normally takes approximately two weeks.
The developer had until the end of that day.
That combination made the request unusually difficult: the team could not simply assemble existing documentation faster, it had to make sound engineering judgment calls on equipment that had not yet been finalized, then build a full technical package around those judgment calls in a fraction of the normal time, without compromising the accuracy or defensibility of the submission.
The E Source Response
Given the tight timeline, we quickly coordinated our resources and assembled a dedicated team to support the request. The team immediately reviewed the client’s existing documents and identified several items that did not fully align with the AESO submission requirements, including some incorrect information that needed to be addressed.
Working against the same-day deadline, the team established technically defensible engineering assumptions to fill the gaps left by incomplete equipment selections, then built out the full technical package required for a System Access Service Request (SASR):
• Project Data Update Package (PDUP), the core technical data record AESO uses to assess the project
• PSS®E power-flow, sequence, and dynamic models reflecting the project's electrical characteristics
• Dynamic test results and a supporting checklist to demonstrate compliance
• A conceptual single-line diagram, clarified and rebuilt from the incomplete preliminary version
• Direct, hands-on support completing the SASR application itself
The team had to work on every piece at the same time instead of one after another. That meant keeping the assumptions lined up across all of them, so the equipment ratings used for the single-line diagram matched what went into the power-flow and dynamic models.
A principal engineer and licensed P.Eng. then completed an expedited technical review and authenticated the required documents after regular business hours, so the package was ready the moment it was needed, and so the client could submit with full confidence in its technical accuracy despite the compressed schedule.
The Result
By 9:00 p.m., the E Source team had worked through the application form and supporting documents with the client and helped ensure that the required materials were ready for submission. The client confirmed that the submission was successfully completed shortly after, ahead of the deadline. Overall, the team provided approximately 9–10 hours of dedicated support that day to help the client meet the critical submission deadline.
The entire package from engineering assumptions, models, test results, and diagrams was completed in approximately nine hours. The client submitted before the Cluster 3 deadline, preserved their eligibility for the cluster, and avoided a project delay that could otherwise have set the development timeline back significantly.
Missing an AESO cluster deadline typically means waiting for the next intake window before an application can be reconsidered, so same-day turnaround was not simply a convenience for this client, it was the difference between staying on schedule and absorbing a delay that would have rippled through financing, procurement, and the project's broader development timeline.
Why it Mattered
This engagement reflects the kind of support E Source is built to provide: deep interconnection engineering expertise paired with the flexibility to compress a normally multi-week scope into hours when a client's timeline leaves no other option. The same rigor that governs a routine two-week engagement, from defensible engineering assumptions through licensed P.Eng. sign-off, was preserved even under an extreme deadline.