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

Heat Exchanger: A component in which thermal energy is transferred from
one fluid to another-for example, a steam generator that transfers thermal en-
ergy from the Heat Transport Fluid to the Working Fluid for a Rankine cycle
steam turbine, or that transfers thermal energy from the Receiver Fluid to the
Heat Transport Fluid (if different).
Heat Tracing: An auxiliary heating system that prevents the freezing of liq-
uids within pipes.
Heat Transport Fluid: The fluid used for transporting or transferring ther-
mal energy from one area to another within the system. See Receiver Fluid;
Working Fluid.
Heliostat: An assembly of mirrors, support structure, drive mechanism, and
mounting foundation which tracks the sun in two axes of motion to continuously
reflect sunlight onto a fixed receiver.
Heliostat Characterization System: See Beam Characterization Sys-
tem.
Heliostat Packing Density: The ratio of total reflective surface area to the
total land area used by the heliostats (concentrator subsystem). Also referred to
as the Ground Cover Ratio.
Hot/Cold Tank Storage: A thermal energy storage system utilizing sepa-
rate tanks for the charged (hot) and uncharged (cold) storage media.
Hours of Storage: The number of hours a plant can produce power at a
stated output level, normally at full-rated system load, when operating exclu-
sively from an initially fully-charged storage unit.
Insolation: The solar energy incident on a unit surface per unit time.
(Acronym for incident solar radiation.)
Intercept Factor: The fraction of direct or reflected rays incident on the
receiver aperture whose trajectories reach the absorber.
Irradiance: See Flux Density.
Levelization: The process by which a series of non-uniform future payments
is converted into a uniform (level) series of payments whose present worth is equal
to that of the original non-uniform series.
Levelized Busbar Energy Cost: The constant annual revenue per unit of
energy required over the lifetime of a plant to compensate for its fixed and vari-
able cost.
Levelized Fixed Charge Rate: The fixed charge rate that produces a con-
stant level of payments over the life of a plant whose present worth is the same as
the present worth of the actual cash flow.
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