A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...

Nameplate Rating: The full-load continuous rating of a power plant under
specified conditions as designated by the manufacturer.
Output Factor: The ratio of the plant energy output for a period of time to
the plant rating over that same time period.
Parasitic Power, Parasitic Energy: The parasitic power is the power re-
quired at any time to operate the power plant (e.g., the power to operate pumps,
motors, computers, lighting, air conditioning, etc.). The parasitic energy is the
energy consumed by such uses for a specified period. The net power produced by
a solar thermal plant is the gross power generated less the parasitic power losses,
and similarly for net energy production.
Peak Load: The maximum load in a given time interval.
Plant Availability: The percentage of time a plant is able to provide power
if so required. Since there is an insolation threshold below which the plant can-
not generate net power, the availability factor is defined as the fraction of total
daylight hours when the solar irradiance exceeds the threshold value.
Pointing Error per Axis: The standard deviation (RMS), for each axis,
of the difference between the desired aimpoint and the beam centroid location.
This error is in the heliostat reflected ray coordinate system and is expressed in
milliradians.
Power Tower: A term used in the popular press to describe a solar thermal
central receiver power system.
Process Heat: The heat which is used in agricultural, chemical, or industrial
operations.
Radiant Power: See Flux (Radiant).
Radiation: The emission and propagation of energy through space (or
through material medium) in the form of waves (or photons).
Rankine Cycle: The thermodynamic cycle upon which water-steam tur-
bines are based, in which the working fluid is pressurized as a liquid, evaporated
and perhaps superheated, put through a turbine to extract its energy, and subse-
quently condensed at low pressure.
Receiver: That element of a solar central receiver system to which solar ra-
diation is directed by the heliostats and where it is absorbed and converted to
thermal energy.
Receiver Fluid: The fluid that is circulated through the receiver to absorb
solar radiation as thermal energy. The Receiver Fluid is normally the same as the
Working Fluid used elsewhere in the system, but may be different (in which case
a Heat Exchanger is required. See Working Fluid; Heat Exchanger.
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