Balakrishna Pamulaparthy

With the ever-growing demand for electricity, large-scale renewable energy integration, and the need to strengthen grid resiliency, utilities are placing significant emphasis on expanding transmission infrastructure. These efforts involve developing modern transmission corridors, high-voltage direct current (HVDC) lines, digital substations, advanced monitoring systems, and grid management technologies to enable efficient long-distance power transfer and better utilization of existing assets. However, the addition of new transmission infrastructure requires long-term planning, regulatory approvals, environmental assessments, complex engineering, substantial capital investment, and extensive coordination among multiple stakeholders. As a result, transmission planning and expansion are often hectic and time-consuming, even as renewable integration and demand growth are progressing at a much faster pace. This mismatch increases stress on transmission corridors and leads to congestion challenges. For example, in the United Kingdom, renewable energy curtailment costs have reached nearly £1 billion annually because 3.8 million MWh of renewable generation had to be curtailed due to transmission congestion, despite being available for production, transmission, and consumption.

According to literature, renewable energy additions will continue at high levels over the next two decades. In fact, in some countries such as the United States, many renewable energy projects remain stuck in grid interconnection queues, awaiting transmission access. Since transmission infrastructure additions take much longer to materialize compared to renewable deployment, innovative solutions are required to maximize the utilization of existing networks, reduce congestion, and minimize curtailment.

In this paper, we propose a novel technology called Dynamic System Rating (DSR), which extends beyond conventional Dynamic Line Rating (DLR). While DLR considers thermal limits as the primary constraint on current flows, these limits are not the only factor restricting capacity. Consequently, DLR data alone often leaves a significant portion of spare capacity underutilized. DSR takes a holistic approach by evaluating not only thermal ratings but also voltage and angular stability margins to determine the true available capacity of each transmission line. This comprehensive assessment ensures that increasing line capacity does not compromise other system stability factors.

Through a case study, we demonstrate how DSR technology enhances network capacity, reduces renewable energy curtailment, and improves overall electricity network utilization, thereby delivering tangible benefits to consumers. By autonomously optimizing power flows, DSR increases effective grid capacity and supports renewable integration, serving as a practical bridge while new transmission corridors are being developed.