By ADAM KANKIEWICZ May 3, 2013
The PV Power Map is a report of national solar resource availability as illustrated by the monthly energy output of a nominal 1-kilowatt DC (kWdc) photovoltaic (PV) system by location. This edition compares PV power output for the months of January and February, and highlights the month-to-month variability real-time energy production can have as a result of seasonal weather conditions.
As the maps illustrate, most of the Eastern Seaboard experienced above average solar energy production in January. Florida’s sunnier-than-average conditions, in particular, led to unusually high PV power output in January. In February, monthly production in the eastern United States saw a significant drop due to wetter-than-average conditions. Energy production around the Great Lakes region was suppressed during both months due to enhanced cloud cover.
Monthly energy production in the Southwest was near-to-above average for both January and February. Meanwhile, energy production jumped significantly in February in the lee of the Rockies, in the Upper Midwest and in the Great Basin region due to drier weather conditions.
To use the PV Power Map to calculate the generation potential of a PV system in a given location, multiply the power output indicated on the map by a project’s capacity, in kilowatts. The result is the total estimated power output for the month. As an example, according to the color charts, the monthly PV power output for a 1 kWdc system in Bozeman, Mont., was approximately 40 kilowatt-hours in January (blue color), and approximately 60 kWh in February (green color). Therefore, a 4-kWdc system in Bozeman would have produced approximately 160 kWh in January (4 kWdc system x 40 kWh) and 240 kWh in February (4 kWdc system x 60 kWh).
The PV Power Map is created with power output estimates generated by SolarAnywhere services from Clean Power Research; these include simulation capabilities and hourly satellite-derived irradiance data with spatial resolutions from 1 to 10 kilometers. The calculations are based on a PV system with a total 1-kWdc nameplate rating that is configured as five 200-watt PV panels with a 1.5-kW inverter; fixed, south-facing panels with 30 degree tilt; no shading; panel PVUSA Test Conditions rating of 178 watts; and inverter efficiency of 95.5 per- cent. Visualization and mapping provided by GeoModel Solar. Access free historical irradiance data at solaranywhere.com.
Adam Kankiewicz (firstname.lastname@example.org) is a research specialist at Clean Power Research.