Why Limited Generation Is Great

California has recently pioneered an innovative approach to enabling more Distributed Energy Resources (DERs) to connect to the grid with a recent decision on Limited Generation Profiles (LGPs).

LGPs allow projects to be approved for grid connection by adhering to schedules that limit how much power they export at different times, based on known grid constraints. This minimizes a project's impact on the electric grid, avoiding the time and cost of complex infrastructure upgrades that might otherwise prevent projects from moving forward.

One of the key advantages of the LGP approach is that it enables networks and utility to embrace DER without the need for full real-time orchestration. As this article from IREC explains:

"The LGP concept is distinct from what is commonly referred to as flexible interconnection in that it does not require a sophisticated communication system to be in place that would enable a utility to actively control DER output. The LGP accomplishes this by relying on the Integration Capacity Analysis to design fixed schedules based upon known grid conditions that have already been modeled and made publicly available."

This approach offers a more immediate path to realizing system benefits and avoiding upgrade costs, and is simpler and quicker for both utilities/networks and project proponents to implement.

Modelling LGPs in Gridcog

Gridcog natively supports modelling time-varying export schedules like California’s LGPs. These schedules automatically curtail DER exports in project simulations and are taken into consideration as part of DER auto-sizing and dispatch optimsiation.

These schedules can be simple daily shapes, like the example below, or more complex schedules with monthly and seasonal variations, or even can reflect specific days and times corresponding to system peak demand events. They can also be coupled with flexible import schedules.

Utilities and project proponents can use this modelling to understand the economic and operational implications of different interconnection arrangements, taking into account network service pricing, electricity supply costs, and opportunities to earn revenue from delivering market and grid services.

Flexible Interconnection

Building new transmission network capacity to host more renewable energy generation is very costly and time-consuming, so the distribution network is emerging the crucial deployment location for new clean energy resources.

LGPs and similar flexible interconnection options are emerging globally as crucial tools for accelerating clean energy deployment. Flexible interconnection options allow projects to proceed more quickly by accepting limited curtailments, enabling more efficient utilization of distrubition network capacity.

Flexible interconnection options are being explored and implemented around the world:

The UK has been at the forefront of flexible connections for several years. National Grid ESO and distribution network operators offer "Active Network Management" schemes, which allow generators to connect to congested parts of the network in exchange for agreeing to curtail output when required. This approach has enabled significant new renewable capacity to connect in areas where traditional reinforcement would have been prohibitively expensive.

Australia has rolled out "Flexible Exports" based on Dymamic Operating Envelopes that DER to export different amounts of power at different times based on real-time network conditions, helping to manage grid congestion.

Beyond California's LGPs, states like New York and Illinois in the United States are piloting more dynamic flexible interconnection approaches that involve real-time orchestration or ‘DERMS’ platforms (Distributed Energy Resource Management Systems).

By giving developers more options and reducing interconnection costs and timelines, flexible approaches like LGPs can significantly improve project economics across various markets. This, in turn, will help drive increased investment in distributed clean energy resources worldwide - a win for developers, utilities, and our global clean energy future.

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