NV Energy Solar Integration Study: Cycling and Movements of Conventional Generators for Balancing Services

With an increasing penetration level of solar power in the southern Nevada system, the impact of solar on system operations needs to be carefully studied from various perspectives. Qualitatively, it is expected that the balancing requirements to compensate for solar power variability will be larger in magnitude; meanwhile, generators providing load following and regulation services will be moved up or down more frequently. One of the most important tasks is to quantitatively evaluate the cycling and movements of conventional generators with solar power at different penetration levels. This study is focused on developing effective methodologies for this goal and providing a basis for evaluating the wear and tear of the conventional generator

Geomagnetic Storms and Long-Term Impacts on Power Systems

Pacific Northwest National Laboratory was commissioned to study the potential impact of a severe GIC event on the western U.S.-Canada power grid (referred to as the Western Interconnection). The study identified long transmission lines (length exceeding 150 miles) that did not include series capacitors. The basic assumption for the study is that a GIC is more likely to couple to long transmission lines, and that series capacitors would block the flow of the induced DC GIC. Power system simulations were conducted to evaluate impacts to the bulk power system if transformers on either end of these lines failed. The study results indicated that the Western Interconnection was not substantially at risk to GIC because of the relatively small number of transmission lines that met this criterion. This report also provides a summary of the Hydro-Québec blackout on March 13, 1989, which was caused by a GIC. This case study delves into the failure mechanisms of that event, lessons learned, and preventive measures that have been implemented to minimize the likelihood of its reoccurrence. Finally, the report recommends that the electric power industry consider the adoption of new protective relaying approaches that will prevent severe GIC events from catastrophically damaging transformers. The resulting changes may increase the likelihood of smaller disruptions but should prevent an unlikely yet catastrophic national-level event