This MIT Study simulated Dynamic Line Ratings across the ERCOT Grid, the results were impressive
DLR would deliver $776M in annual congestion savings in ERCOT - more than double the amount with AARs. Adopting DLR would yield over 2x the benefits compared to AAR.
In a recent paper published by MIT, titled "Impacts of Dynamic Line Ratings on the ERCOT Transmission System," researchers explored the potential benefits of implementing Dynamic Line Ratings (DLR) through a comparison between DLR, Ambient Adjusted Ratings (AAR), and Static Line Ratings (SLR) on a synthetic Electric Reliability Council of Texas (ERCOT) grid. This research is incredibly important in a time when our grid is in need of 47,000 more GW-miles of transmission by 2035, while the interconnection queue continues to grow above 2 Terawatts of total generation and storage capacity now seeking connection to the grid (over 95% of which is for zero-carbon resources like solar, wind, and battery storage)
Dynamic Line Ratings refer to the practice of continuously monitoring and adjusting the capacity of transmission lines based on real-time conditions, such as the conductor’s temperate, ambient air temperature, and local wind speed, rather than relying on fixed ratings that do not take into account variable factors. By using DLR, grid operators can optimize the use of existing transmission infrastructure without the need for costly upgrades. The results of this study suggest that implementing DLR across the ERCOT grid could result in various benefits, including reduced congestion, increased economic efficiency, and improved grid reliability and resilience.
The estimates of DLR and AAR were calculated based on heat balance physics and high-resolution weather data of temperature and wind velocities. The paper developed a constraint generation method for contingency screening to solve security-constrained optimal power flow.
The study conducted simulations with SLR, AAR, or DLR implementations and found that compared to an annual cost of $10.3 billion when using SLR, using AAR and DLR reduces system costs by $356 million and $776 million. These savings can be found from the reduction of congestion costs, where AAR and DLR achieve 35% and 77% cost savings, respectively.
Moreover, the study noted that DLRs can play a critical role in supporting the integration of renewable energy sources into the grid. As renewable generation can be variable and unpredictable, DLR can help manage transmission capacity and avoid curtailment of renewable resources. The study also found that using AAR on the ERCOT grid could result in the additional dispatch of 160 megawatts of solar and 800 MW of wind while introducing DLR results in 360 more MW of solar and 2.25 terawatts of wind. The Implementation of DLR in this scenario would result in 2.83 million metric tons of CO2 avoided.
In summary, this study demonstrates the potential value of DLRs in improving grid capacity, resilience, and safety. Given the increasing demand for electricity and growing interest in renewables, DLR implementation is an essential step toward a more efficient, reliable, and sustainable energy future.