Glossary of Solar Radiation Resource Terms

Other relevant glossaries


The following links allow you to move to the words beginning with that letter.

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Dewpoint - the temperature at which the water in the atmosphere will condense as drops on a surface.


Diffuse Horizontal Irradiance - synonym for diffuse sky radiation.


Diffuse Sky Radiation - the radiation component that strikes a point from the sky, excluding circumsolar radiation. In the absence of atmosphere, there should be almost no diffuse sky radiation. High values are produced by an unclear atmosphere or reflections from clouds.

Click Shining On (Figure 3) to see solar components


Direct Normal Irradiance - synonym for beam radiation, the amount of solar radiation from the direction of the sun.

Click Shining On (Figure 3) to see solar components


Diurnal - daily, or the daily cycle. A diurnal plot is usually a representative midnight-to-midnight graph of values measured at a smaller time interval (e.g., hourly or 5-minute values).


DOE - in this context, always refers to the United States Department of Energy, although other departments may have the same acronym.


Dry-bulb Temperature - air temperature measured with a thermometer, similar to ambient temperature. The term "dry-bulb" distinguishes it from the wet-bulb temperature measured by a psychrometer to determine relative humidity.


The following links allow you to move to the words beginning with that letter.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z



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