 |
Glossary of Solar Radiation Resource Terms |
|
Other relevant glossaries
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
Langley -
Named for Samuel P. Langley (1834-1906), a pioneering solar energy researcher at the
Smithsonian Institution, this unit of radiant flux
is one calorie per square centimeter (cal/cm2).
Latitude -
the angular distance from the equator to the pole. The equator is 0°, the North Pole
is 90° North, and the South Pole is 90° South.
Light -
usually the visual portion of the
electromagnetic spectrum between
infrared (about 8000 Angstroms or 800 nanometers(nm)) and ultraviolet
(about 4,000 Angstroms or 400 nm); however, the term is sometimes used as a synonym for
all electromagnetic radiation.
Line-focusing Concentrator -
a system that tracks the path of the sun by pivoting on one axis (typically East-West or
North-South), using shiny parabolic troughs to heat the collector fluid that passes through
a tube at the focus. It derives its name from the fact that solar radiation is focused
on a line instead of on a point. Below is an illustration from the
Solar Radiation Data Manual for Flat Plate and Concentrating
Collectors .
Local Apparent Time -
The time of day based strictly on the
longitude
of the locality and not on "blocky" time
zones. For example, when it is 12:00 Pacific Standard Time (USA) (assumed to be
120° West Longitude), it is 11:51 Local Apparent Time in Seattle,
Washington (USA), at 122° 18' West Longitude.
Local Standard Time -
The time of day based on the
longitude
of the zone meridian associated with a locality. In the USA, the zone meridians
are known by the following names:
LONGITUDE NAME
75° West Eastern Standard Time
90° West Central Standard Time
105° West Mountain Standard Time
120° West Western Standard Time
135° West Alaska Standard Time
150° West Hawaii Standard Time
Longitude -
the East-West angular distance of a locality from the Prime Meridian. The
Prime Meridian is the location of the Greenwich Observatory in England and all points
North and South of it.
Longwave Radiation -
infrared radiation,
radiation with wavelengths greater than those of the visible light
(at about 8000 Angstroms or 800 nanometers(nm)) but shorter than those of microwaves
(at about 1,000,000 Angstroms or 800,000 nm). Longwave radiation is associated with
heat energy.
Lux -
The International Standard (SI) unit of measure for luminous flux density
at a surface. One Lux equals one lumen per square meter.
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
Please send questions and comments to
rredc@nrel.gov
Disclaimer and copyright notice.
Return to RReDC home page ( http://www.nrel.gov/rredc )
