Resumen:
Non-firm (flexible) grid connection agreements are emerging as a fast, lower-cost alternative to traditional firm access for integrating renewable and distributed energy resources (DERs). This review examines: Which types of non-firm agreements exist, how are they implemented, and what lessons can be drawn from recent regulatory pilots?
Literature and pilot projects reveal four predominant models of non-firm grid connections: capacity-limited, time-limited, dynamic operating envelopes, and fully flexible based access. These models are being formalised through legislation or regulatory guidance in the United Kingdom, Australia, Spain, and in various countries of the European Union. Their implementation is increasingly supported by digital monitoring and growing links to local flexibility markets.
Flexible connections can reduce connection costs by up to 80% and halve leadtimes, while safely expanding hosting capacity. Key challenges are curtailment predictability, compensation, and alignment with emerging market platforms. Clear, standardised regulatory frameworks and interoperable digital solutions are essential for scaling these agreements and accelerating DER integration.
Resumen divulgativo:
Este artículo presenta una revisión de los principales tipos de acuerdos de conexión a red no firmes (flexibles) existentes y del panorama regulatorio en las jurisdicciones más relevantes dentro y fuera de la UE.
Referencia DOI:
https://doi.org/10.1007/s40518-025-00268-7
Publicado en papel: Diciembre 2025.
Publicado on-line: Agosto 2025.
Cita:
M. Romeo Monterde, E. F. Álvarez, M. Valarezo, "Non-Firm Grid Connections: A Review of Access Types, Mechanisms, and Regulatory Frameworks", Current Sustainable/Renewable Energy Reports, Vol. 12, nº. 1, pp. 23, Diciembre 2025. [Online: Agosto 2025] doi: 10.1007/s40518-025-00268-7