Abstract: . . .  Demand (kW) 3.4 Solar Irradiance Effects The pyranometer used in the DAS measures plane-of-array (POA) irradiance, which includes both direct normal (direct sunlight) and diffuse (light reflected off of clouds, etc.). A LI-COR pyranometer was used to measure solar irradiance in watts per square meter units. Solar irradiance directly affects the performance of the PV system's output power. This is exemplified in the following chart that plots output power vs. solar irradiance, for data in which solar irradiance is above 500 W/m2. This value was chosen due to the nonlinearity exhibited by data points under 500 W/m2, which would alter the slope of the straight line drawn through the data points. In addition, 500 W/m2 was selected by the Utility PhotoVoltaic Group (UPVG) as the reference threshold above which to evaluate the performance of PV systems. San Diego Carport PV Data Analysis for April 1999 Output Power vs. Solar Irradiance 4.0 3.0 Output Power (kW) y = 0.0031x + 0.1845 2.0 1.0 0.0 0 200 400 600 800 1000 1200 Solar Irradiance (W/m²) Figure 11. Output Power vs. Solar Irradiance - April 1999 3.5 Temperature Effects Temperature has an inverse relationship to output power in PV arrays. The EV Solar Chargeport is installed in a cooler climate, are therefore the temperature effects are not as significant as in warmer regions. The following chart does show that the within a range of 50 W/m2 solar irradiance (for the month of April 1999), increasing temperature results in decreased . . .
. . .  operated reliably between November 1998 and July 1999, without any requirements for maintenance actions on any of the components. It has provided a charging station for users of EVs in the downtown San Diego area. The data collected has provided SDG&E with insight into the daily operations of the system's PV system, as well as a record of EV charger utilization. The results quantified in this report show that the chargeport also provides an element of grid support to the local utility by generating power during the day, when the chargers are typically consuming energy. The overall system has been an effective demonstration of an EV Solar Chargeport. 15 Appendix 1: Monthly Data Charts The following shows data charts for each month the EV Solar Chargeport was monitored. November 1998 San Diego Carport PV Data Analysis for November 1998 Daily Energy Production 25 20 Energy Produced (kWh) 15 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Figure A- 1. Daily Energy Production - November 1998 16 San Diego Carport PV Data Analysis for November 1998 Peak Output Power and Peak Solar Irradiance 4000 1200 3500 1000 3000 800 2500 2000 600 1500 400 1000 200 500 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 November 1998 Peak Output Power (Watts) Peak Solar Irradiance (Watts/m²) 0 Figure A- 2. Peak Power and Peak Solar Irradiance - November 1998 4000 San Diego Carport PV Data Analysis for November 1998 Output Power vs. . . .
--3000,2,750,3167,154071