System for tuning a photovoltaic power generation plant forecast with the aid of a digital computer

A system for tuning simulated plane-of-array irradiance for use in a photovoltaic power generation forecast with the aid of a digital computer, comprising:

• at least one irradiance sensor configured to regularly measure over an observation period a time series of solar irradiance values for a physical location at which a photovoltaic power generation plant is situated;
• a computer comprising a processor coupled to a memory storing computer-executable code, the processor configured to:
• regularly obtain ambient temperature for the physical location;
• regularly obtain the time series of solar irradiance values from the irradiance sensor;
• obtain the photovoltaic array configuration of the photovoltaic power generation plant, and global horizontal irradiance, global horizontal irradiance clear sky indexes, and wind speeds as measured over the observation period for the physical location;
• simulate a time series of global horizontal irradiance over the observation period comprising each solar irradiance value as adjusted by the global horizontal irradiance clear sky index corresponding to the solar irradiance value;
• simulate plane-of-array irradiance observations from the simulated global horizontal irradiance and the photovoltaic array configuration for the physical location over a forecast period;
• evaluate an irradiance adjustment function, comprising:
• correlate the measured and the simulated global horizontal irradiance by respective times of measured and simulated observation over the observation period;
• bin the measured and the simulated global horizontal irradiance as correlated along a continuum of the global horizontal irradiance clear sky indexes;
• and
• form the irradiance adjustment function by evaluating a ratio of and minimizing error between the measured global horizontal irradiance to the simulated global horizontal irradiance at each global horizontal irradiance clear sky index;
• and
• regularly adjust each simulated plane-of-array irradiance observation by the irradiance adjustment function based on the global horizontal irradiance clear sky index corresponding to the simulated plane-of-array irradiance observation;
• simulate temperatures for the photovoltaic generation plant over the forecast period based on the adjusted simulated plane-of-array irradiance observations and both the ambient temperatures and the wind speeds as measured over the observation period for the physical location;
• quantify average parasitic losses by the plant, comprising:
• sum total nighttime power consumption over the forecast period;
• and
• divide the total nighttime power consumption by a total number of nighttime service hours;
• and
• forecast the power generation by the photovoltaic power generation plant over the forecast period based upon the adjusted simulated plane-of-array irradiance, the simulated photovoltaic module temperatures, a value of the average parasitic losses that corresponds to each simulated input power level, and the photovoltaic array configuration.

A system for tuning power generation performance for use in a photovoltaic power generation forecast with the aid of a digital computer, comprising:

• at least one irradiance sensor configured to regularly measure over an observation period a time series of solar irradiance values for a physical location at which a photovoltaic power generation plant is situated;
• and
• a computer comprising a processor coupled to a memory storing computer-executable code, the processor configured to:
• regularly obtain the time series of solar irradiance values from the irradiance sensor;
• regularly obtain ambient temperature for the physical location;
• obtain the photovoltaic array configuration of the photovoltaic power generation plant, and global horizontal irradiance, global horizontal irradiance clear sky indexes, wind speeds, and alternating current outputs of the photovoltaic power generation plant as measured over the observation period for the physical location;
• simulate a time series of global horizontal irradiance over the observation period comprising each solar irradiance value as adjusted by the global horizontal irradiance clear sky index corresponding to the solar irradiance value;
• simulate plane-of-array irradiance observations from the simulated global horizontal irradiance and the photovoltaic array configuration for the physical location over a forecast period;
• simulate photovoltaic module temperatures for the photovoltaic generation plant over the forecast period based on the simulated plane-of-array irradiance observations and both the ambient temperatures and the wind speeds as measured over the observation period for the physical location;
• forecast power generation by the photovoltaic power generation plant over the forecast period based on the simulated plane-of-array irradiance, the simulated photovoltaic module temperatures, and the photovoltaic array configuration;
• evaluate a power conversion efficiency curve function, comprising:
• simulate power generation by the photovoltaic power generation plant over the observation period based on the simulated plane-of-array irradiance, the simulated photovoltaic module temperatures, and the photovoltaic array configuration;
• bin the measured alternating current outputs and the simulated power generation by simulated input power level;
• and
• form the power conversion efficiency curve function by minimizing error between and evaluate a ratio of the measured alternating current outputs to the simulated power generation at each simulated input power level;
• quantify average parasitic losses by the plant, comprising:
• sum total nighttime power consumption over the forecast period;
• and
• divide the total nighttime power consumption by a total number of nighttime service hours;
• and
• regularly adjust the forecast power generation by the power conversion efficiency curve function corresponding to each simulated input power level function and by a value of the average parasitic losses that corresponds to each simulated input power level.