SE Engr. Solar Resource Assessment and Meteorology 1

Question 1

What is the standard unit of measurement for solar irradiance?

Accepted Answer

W/m²

Answer

Solar irradiance is the instantaneous power of solar radiation per unit area, measured in watts per square meter (W/m²).

Question 2

How is Global Horizontal Irradiance (GHI) mathematically defined?

Accepted Answer

DNI × cos(θz) + DHI

Answer

GHI equals the direct normal irradiance projected onto the horizontal plane (DNI × cosine of the solar zenith angle) plus the diffuse horizontal irradiance (DHI).

Question 3

What does DNI stand for in solar resource assessment?

Accepted Answer

Direct Normal Irradiance

Answer

DNI stands for Direct Normal Irradiance, the solar radiation received per unit area by a surface always held perpendicular to the sun's rays.

Question 4

Which instrument is specifically designed to measure Direct Normal Irradiance (DNI)?

Accepted Answer

Pyrheliometer

Answer

A pyrheliometer, mounted on a solar tracker to continuously point at the sun, measures the direct beam (DNI) component of solar radiation.

Question 5

What is the clearness index (Kt) in solar resource characterization?

Accepted Answer

Ratio of GHI to extraterrestrial horizontal irradiance

Answer

The clearness index (Kt) is the ratio of GHI measured at the surface to the extraterrestrial horizontal irradiance, indicating how much solar radiation is transmitted through the atmosphere.

SE Engr. - Solar Energy Engineering Certification Practice Test

SE Engr. - Solar Energy Engineering Certification Practice Test

SE Engr. Solar Resource Assessment and Meteorology 1