Applying battery energy storage to enhance the benefits of photovoltaics

Abstract

Renewable resources are becoming more and more obtainable and affordable due to the development of technology and the enactment of government policies. Electric utilities are required to deliver reliable power to customers and must operate utility grids within strict voltage limits. As renewable energy becomes a larger player amongst the resources supplying energy to these grids, issues begin arising due to the intermittent nature of these resources. The output from solar power aligns reasonably well daytime consumption on the electricity grid, reducing the need for new coal power stations. However, high penetration photovoltaic (PV), can lead to voltage instability due to intermittencies related to cloud cover. If the PV power is injected into a power system directly on a large scale, it may produce issues related to dispatchability, reliability and stability. It is desirable to select a smoothing storage algorithm that would filter out the highest rate transitions, but would still be fast enough to avoid significant lag with respect to current power production. For traditional testing, a moving average algorithm was used. For comparison, the author has tested two other algorithms. The results are being compared, showing that the dual moving average smoothing algorithm has merits in improving smoothness.