Influence of photovoltaic power generation on required capacity for load frequency control

We developed a mathematical model to evaluate the impact of small (rooftop) photovoltaic (PV) power-generating stations on economic and performance factors for a larger scale power system, and applied this model to the Tokyo metropolitan area. We used solar radiation data from five local meteorological stations to estimate both the individual and aggregate contributions of the projected PV stations to the local power grid. We found that an electrical power system containing a 10% contribution from PV stations would require a 2.5% increase in load frequency control (LFC) capacity over a conventional system. The break-even cost for PV power generation was found to be relatively high for contribution levels of less than 10%. Higher proportions of PV power generation gave lower break-even costs, but economic and LFC considerations imposed an upper limit of about 10% on PV contributions to the overall power systems