A methodology for quantifying variability of renewable energy sources by reserve requirement calculation

Most of the major renewable power sources, such as solar, wind, and ocean wave, are variable in time. Variability arises from local turbulence, weather patterns, clouds, diurnal variations, and seasonal variations. The variable, non-dispatchable nature of renewable power sources requires an increase in the utility reserve requirement to maintain reliability. Power sources with greater minute-to-minute and hourly variation require greater reserves. This paper presents a methodology for quantifying the variability of renewable power sources based on calculating the utility reserve requirement over short and medium time scales.