For data centers, hospitals, REITs, and financial institutions, power procurement is no longer just a utility decision—it’s a mission-critical business priority. Whether expanding a campus, adding new facilities, or securing redundancy, large energy users must navigate the ISO interconnection process to access wholesale power.
But here’s the challenge: ISO large load interconnection applications were built for generators and transmission owners—not for end-use customers like you. That means if you don’t “speak the ISO’s language,” delays, cost surprises, and miscommunication can derail your project.
At ECM, with over 20 years of direct ISO market experience, we help Fortune 500 clients translate the complexity into a clear, predictable path to reliable power.
What Energy Executives Need to Know About ISO Interconnections
- Independent System Operator (ISO): Manages the grid, schedules wholesale energy, and ensures system reliability. ISOs like NYISO, PJM, and ISO-NE evaluate your load request for impacts on transfer capacity, voltage, congestion, and thermal limits.
- Transmission Owner (Utility): Delivers power from substations to your site. If the ISO identifies risks, the TO must design and implement upgrades or reinforcements.
- Large Load Customer (You): Ultimately responsible for some of the cost allocations tied to required system upgrades caused by the creation of your project. Without a clear strategy, those costs can escalate quickly.
Common Pitfalls in Large Load Applications
- Mismatched Information: ISO applications often request data irrelevant to load customers, leaving gaps that slow reviews.
- Acronym Overload: Terms like TTC, N-1, LMP, and CRR may be second nature to grid operators but can leave large customers guessing.
- Unclear Roles: The ISO doesn’t “approve or deny”—they study, model, and propose. The utility decides whether and how to implement.
Without experience, it’s easy to misinterpret what’s negotiable and what’s not.
Proven Strategies for a Successful Interconnection
- Learn the ISO’s Language: Every ISO publishes a glossary. Familiarizing your team with terminology accelerates approvals.
- Engage Early with Both ISO & TO: Build credibility by addressing their concerns upfront—voltage stability, congestion costs, and thermal limits.
- Plan for Cost Allocation: Utilities will assign upgrade costs. Having the proper engineering group evaluate proposed upgrades can help estimate future costs.
- Partner with Experts: Advisors fluent in ISO procurement and large load interconnections can shorten timelines and reduce risk.
Why This Matters for Large Energy Users
- Data Centers: Interconnection delays mean stranded capital and missed market opportunities.
- Financial Institutions: Power access directly affects business continuity and disaster recovery planning.
- REITs & Commercial Real Estate: Tenant retention depends on reliable, competitively priced power.
- Healthcare Systems: Hospitals require uninterrupted, resilient energy supply for critical operations.
In regions like NYISO, PJM, and ISO-NE, where grid constraints are tightening and demand is rising, the ability to navigate ISO interconnections is a competitive advantage.
ECM: Your Partner in ISO-Direct Procurement
For over 20 years, ECM has guided complex organizations through the ISO interconnection process, from application through negotiation and final cost allocation. We ensure your project speaks the ISO’s language—so you secure reliable power faster, at the best possible cost.
Contact ECM today to discuss how ISO-direct procurement can support your next expansion or energy strategy.
About Margie Miller
Margie Miller is Vice President of Procurement Operations at ECM. With more than two decades of experience working directly with ISOs and utilities, she has led countless large-load interconnection projects across NYISO, PJM, and ISO-NE. Margie is known for bridging the gap between highly technical grid requirements and the practical needs of Fortune 500-scale energy consumers, ensuring projects are delivered on time and on budget.
About ECM
ECM is an energy management services firm with a 20+ year track record of success in wholesale ISO-direct power procurement, renewable integration, demand response, and energy optimization. Serving data centers, healthcare systems, financial institutions, REITs, and other Fortune 500 enterprises, ECM helps clients secure reliable power, reduce costs, and achieve sustainability goals across NYISO, PJM, and ISO-NE. With a 100% success rate, ECM is the trusted partner for organizations where energy is mission-critical.