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Highlights
  • over 200 satellite-derived meteorology and solar energy parameters
  • monthly averaged from 22 years of data
  • data tables for a particular location
  • GIS Web Mapping Application & Services
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  Data Retrieval:
Meteorology and Solar Energy Meteorology and
  Solar Energy  
Web Mapping GIS Web Mapping Application & Services
Renewable Software Application Inputs Renewable Software
Application Inputs

  Supporting Documentation:
Acknowledgement Acknowledgement for data usage
Geometry Horizontal Grid for
Input and Output
Accuracy Accuracy
Methodology Methodology
Parameters Parameters (Units & Definition)
Parameter       (Units)
Definition

Parameters for Solar Cooking:
Average insolation       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth. Also referred to as total or global solar radiation.
Midday insolation       (kWh/m2/day)
Average insolation available within 1.5 hours of Local Solar Noon.
Clear sky insolation       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth when the cloud cover is less than 10%.
Clear sky days       (days)
Number of clear sky days when the cloud cover is less than 10%.

Parameters for Sizing and Pointing of Solar Panels and for Solar Thermal Applications:
Insolation on horizontal surface       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth. Also referred to as total or global solar radiation. The average and percent difference minimum and maximum are given.
Diffuse radiation on horizontal surface       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth under all-sky conditions with direct radiation from the Sun's beam blocked by a shadow band or tracking disk at the Earth's surface.
Direct normal radiation       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) at the Earth's surface on a flat surface perpendicular to the Sun's beam with surrounding sky radiation blocked.
Insolation at 3-hourly intervals       (kW/m2)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth.
Insolation clearness index       (dimensionless)
Fraction of insolation at the top of the atmosphere which reaches the surface of the earth.
Insolation normalized clearness index       (dimensionless)
Zenith angle-independent expression of the insolation clearness index.
Clear sky insolation       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident on the surface of the earth when the cloud cover is less than 10%.
Clear sky insolation clearness index       (dimensionless)
Fraction of insolation at the top of the atmosphere which reaches the surface of the earth during clear sky days (cloud amount < 10%).
Clear sky insolation normalized clearness index       (dimensionless)
Zenith angle-independent expression of the clear sky insolation clearness index.

Solar Geometry:
Solar Noon       (GMT time)
The time when the sun is due south in the northern hemisphere or due north in the southern hemisphere.
Daylight Hours       (hours)
Time between sunrise and sunset.
Daylight average of hourly cosine solar zenith angles       (dimensionless)
The average cosine of the angle between the sun and directly overhead during daylight hours.
Cosine solar zenith angle at mid-time between sunrise and solar noon       (dimensionless)
Approximate monthy average ratio of horizontal surface solar beam radiation to direct normal radiation.
Declination       (degrees)
The angular distance of the sun north (positive) or south (negative) of the equator.
Sunset Hour Angle       (degrees)
The angle that the earth has rotated between the time of solar noon and sunset.
Maximum solar angle relative to the horizon       (degrees)
The maximum vertical angle of the sun above the horizon.
Hourly solar angles relative to the horizon       (degrees)
The vertical angle of the sun above the horizon.
Hourly solar azimuth angles       (degrees)
The arc of the horizon measured clockwise from true north, to the point where a vertical circle through the sun intersects the horizon.

Parameters for Tilted Solar Panels:
Radiation on equator-pointed tilted surfaces       (kWh/m2/day)
Radiation on tilted surfaces is calculated from the monthly average insolation on a horizontal surface. Tilt angles are 0, latitude - 15, latitude, latitude + 15, 90, and the optimum angle. The optimum angle provides the monthly averaged maximum radiation.
Minimum radiation for equator-pointed tilted surfaces       (kWh/m2/day)
Radiation on tilted surfaces is calculated from the monthly minimum insolation on a horizontal surface. Tilt angles are 0, latitude - 15, latitude, latitude + 15, 90, and the optimum angle. The optimum angle provides the monthly averaged maximum radiation.
Maximum radiation for equator-pointed tilted surfaces       (kWh/m2/day)
Radiation on tilted surfaces is calculated from the monthly maximum insolation on a horizontal surface. Tilt angles are 0, latitude - 15, latitude, latitude + 15, 90, and the optimum angle. The optimum angle provides the monthly averaged maximum radiation.

Parameters for Sizing Battery or other Energy-storage Systems:
Minimum available insolation as % of average values over consecutive-day period (1, 3, 7, 14, and 21 days)       (dimensionless)
This parameter is based on minimum consecutive-day insolation over various numbers of days within the month.
Horizontal surface deficits below expected average values over consecutive-day period (1, 3, 7, 14, and 21 days)       (kWh/m2)
Deficits below expected average values over consecutive-day period.
Equivalent number of NO-SUN days over consecutive-day period (1, 3, 7, 14, and 21 days)       (days)
Hypothetical number of days for which no solar insolation is available.

Parameters for Sizing Surplus-product Storage Systems:
Available surplus as % of average values over consecutive-day period (1, 3, 7, 14, and 21 days)       (dimensionless)
Available surplus as % of average values over consecutive-day period.

Cloud Information:
Daylight cloud amount       (percent)
Percent of cloud amount during daylight within a region.
Cloud amount at 3-hourly intervals       (percent)
Percent of cloud amount within a region.
Frequency of cloud amount at 3-hourly intervals       (percent)
Percent of time the cloud amount is less than 10%, between 10 - 70%, and greater than 70% within a region.

Meteorology (Temperature):
Air Temperature       (° C)
Daily Temperature Range       (° C)
Difference between the average daily maximum and average daily minimum.
Cooling Degree Days above 18° C       (degree days)
The monthly accumulation of degrees when the daily mean temperature is above 18° C.
Heating Degree Days below 18° C       (degree days)
The monthly accumulation of degrees when the daily mean temperature is below 18° C.
Arctic Heating Degree Days below 10° C       (degree days)
The monthly accumulation of degrees when the daily mean temperature is below 10° C.
Arctic Heating Degree Days below 0° C       (degree days)
The monthly accumulation of degrees when the daily mean temperature is below 0° C.
Earth Skin Temperature       (° C)
The Earth skin temperature is meant to approximate the temperature right at the surface including the vegetated ground coverage. Thus, surfaces with less vegetation will warm in the sunlight than vegetated surfaces and cool more at night.

Daily Mean Earth Temperature minimum, maximum and amplitude       (° C)

Frost Days       (days)
The number of days for which the temperature falls below 0 degrees Celsius.
Dew/Frost Point Temperature       (° C)
Temperature at which air is saturated with water vapor.

Meteorology (Wind):
Wind speed at 50 m       (m/s)
The average and percent difference minimum and maximum are given.
Percent of time for ranges of wind speed at 50 m       (percent)
Percentage [frequency] of time that wind speed is in each range (0-2, 3-6, 7-10, 11-14, 15-18, 19-25 m/s).
Wind Speed at 50 m at 3-hourly intervals       (m/s)
Wind Direction at 50 m       (degrees)
Wind Direction at 50 m at 3-hourly intervals       (degrees)
Wind Speed at 10 m for terrain similar to airports       (m/s)
Wind Speed adjustments for height and vegetation type       (m/s)
Wind speeds at 50 m may be adjusted to heights from 10 to 300 meters using the Gipe power law. Wind speeds may be adjusted for different terrain by selecting from 17 vegetation types.

Meteorology (Other):
Relative Humidity       (percent)
Ratio of actual partial press of water vapor to the partial pressure at saturation, expressed in percent.
Specific Humidity       (kg/kg)
Mass of water vapor carried by unit mass of dry air (kg water/kg dry air).
Atmospheric Pressure       (kPa)
Total Column Precipitable Water       (cm)
Total atmospheric water vapor contained in a vertical column of unit cross-sectional area extending from the surface to the top of the atmosphere.
Precipitation       (mm/day)
The average daily rain rate based upon the total monthly averaged amount of rain for the given month divided by the number of days in the month.

Supporting Information:
Top-of-atmosphere insolation       (kWh/m2/day)
Amount of electromagnetic energy (solar radiation) incident at the top of the atmosphere.
Surface Albedo       (dimensionless)
Fraction of insolation reflected by the surface of the earth.

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 Document generated on Fri Jul 21 06:41:31 EDT 2017