Duke Energy Progress has found that 24 solar and solar-plus-storage projects it solicited would require transmission upgrades costing an average of $190 per kW of capacity, and requiring an average of 4.5 years to build, to avoid thermal overloads on the grid that could result from the added power those projects could deliver.
Those costs would be 72% lower, two researchers now report, if the projects had been evaluated for flexible “connect and manage” interconnection service, technically known as energy resource interconnection service (ERIS). Under that approach, projects would be required to occasionally curtail their output so they would not thermally overload transmission lines.
Using software that is widely used by transmission providers, the researchers first replicated the Duke Energy Progress cluster study and then modeled a scenario based on flexible interconnection. In that scenario, the number of grid elements such as transmission lines and transformers that required investments to avoid thermal overloading was reduced by 75%, thus reducing costs.
Costs to avoid thermal overloading represented 75% of the overall upgrade costs reported in the utility’s study, with the remaining costs due to network upgrades at the point of interconnection and at remote ends of the line for relaying and communication, the utility reported. The researchers did not model those other costs under flexible interconnection.
Lead researcher Tyler Norris, a Duke University Ph.D. candidate and former Cypress Creek Renewables executive, reported the findings to the Federal Energy Regulatory Commission (FERC) in advance of a commission workshop on “Innovations and Efficiencies in Generator Interconnection.”
The 24 projects include state and FERC jurisdictional interconnection requests. North Carolina, the primary location for the 24 projects studied, does not allow flexible interconnection for state-jurisdictional projects.
Faster agreement
A shorter timeframe to reach an interconnection agreement can also be available under flexible interconnection.
In the ERCOT grid region in Texas, where flexible interconnection is used for all utility-scale projects, Norris and a co-author reported in a second study described in the same FERC filing a relatively quick 21-month average timeframe from an interconnection request to an interconnection agreement.
That compares to a 38-month timeframe in other grid regions for projects interconnecting with the widely used “network resource interconnection service” (NRIS), which does not require occasional curtailment.
Unfortunately, those other grid regions had a nearly identical timeframe to reach an interconnection agreement for projects seeking flexible “connect and manage” or ERIS interconnection, as for projects seeking NRIS interconnection.
The researchers said “it is reasonable to assume that the similarity in study methods for ERIS and NRIS outside ERCOT, and the oft-comparable network upgrade costs, is a significant factor” that could explain why non-ERCOT jurisdictions do not achieve the faster flexible interconnection that ERCOT achieves.
Norris previously described how flexible interconnection can benefit ratepayers and utility staff as well as project developers, and elaborated on those and other advantages, as well as some disadvantages, in the FERC filing.
Co-authoring the two studies with Norris were, for the first study, Ryan Watts, director of grid integration engineering at Cypress Creek Renewables, and for the second study, Duke University Associate Professor Dalia Patino-Echeverri.
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The Congress and FERC needs to Legislate / Enforce “THE RIGHT TO CONNECT” to ALL POLLUTION-FREE FACILITIES to support Rapid Deployment of these Pollution Free Facilities. (If The People, already, have a similar right to Access the Grid, who not Solar Facilities?). These Facilities ALL end up REDUCING POLLUTION that just spreads Premature Death, Suffering and Environmental Degradation, in addition to (allegedly) causing Climate Change etc…
In addition, the above should Legislate & Enforce PRINCIPLE #16 of the 1992 UN Rio Agreement, already accepted by the US and 200 Nations, that THE POLLUTERS MUST PAY (PMP) for the Damage & Societal Costs caused by Pollution.
A Global, Uniform, Fair & Just PMP Levy of $0.28/KWhe on the 130Trillion KWhe/yr of Global Energy Used today, can provide $36.5 Trillion/yr and Offset, just the Societal Costs, around thd Global to Finance the transition of the world from a Polluted-n-Dirty World to a ZERO POLLUTION EARTH.. using the $400 Trillion, PAID ONLY BY THE POLLUTERS, in a Dozen Years.
The POLLUTERS the USA would provide $15+Trillion/yr from the 60TrillionKWh/yr of Energy Used in the USA today… !!!!
May I need to say more…!!!!