SolarCollector:FlatPlate:Water
Used in:
- Solar hot water loop, demand side
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Used in:
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Solar hot water collectors are thermal devices that convert solar energy into thermal energy by raising the temperature of a circulating heat transfer fluid (which must be water in current versions of EnergyPlus). The fluid is used to heat water for DHW usage and/or space heating. In EnergyPlus solar collectors are components that are connected to a solar plant loop. A solar heating system can be constructed with a combination of solar collectors, pumps, and hot water tanks.
The EnergyPlus model is based on the equations found in the ASHRAE standards and Duffie and Beckman (1991). This model applies to glazed and unglazed flat-plate collectors, as well as banks of tubular, i.e. evacuated tube, collectors.
The solar collector object references a solar collector surface which is defined in the building model and defines the gross area, position, orientation and tilt of the collector allowing it to participate normally in detailed solar and shading calculations if either of the 2-Full exterior or 3-Full interior and exterior Solar distribution options are selected. Solar radiation incident on the collector surface includes beam and diffuse radiation, as well as radiation reflected from the ground and adjacent surfaces. Shading of the collector by other surfaces, such as nearby buildings or trees, is also taken into account. Likewise, the collector surface can shade other surfaces, for example, reducing the incident radiation on the roof beneath it.
The thermal and optical properties of the collector module can be loaded from a Solar collector template.
The unique name of the Solar hot water collector.
The maximum flow rate (in m3/s or gal/min) allowed through the collector.
Select a building solar collector surface o define the gross area, position, orientation and tilt of the collector.
Check this option to identify this Solar collector as the one to be used as a reference point for the differential thermostat selected on the Solar loop dialog.
A Solar collector performance template which defines the thermal and optical properties of the collector.
DesignBuilder provides a database of Solar collector templates containing the thermal and optical performance parameters for a single collector module. These parameters are based on the testing methodologies described in ASHRAE Standards 93 and 96. The Solar Rating and Certification Corporation (SRCC) applies these standards in their rating procedures of solar collectors. The coefficients for the energy conversion efficiency and incident angle modifier allow first order (linear) or second order (quadratic) correlations. To use a first order correlation, the second order coefficient must be set to zero.
In order for the model to work correctly, the test conditions for which the performance coefficients were measured must be specified in the fields: Test flow rate, and Test correlation type. Currently, only water is allowed as the Test Fluid.
More detailed information about the performance coefficients, can be found in the EnergyPlus Engineering Reference Document.
The gross area of the collector module (in m2 or ft2). This value is mainly for reference. The area of
the associated solar collector surface is used in all calculations.
The volumetric flow rate during testing (m3/s or gal/min). If the value is available as flow rate per unit
area, it is recommended to multiply by the Gross Area of the collector module, not the net aperture area.
This field specifies type of temperature used to develop the correlation equations. The testing procedure is based on an experimental correlation using either Inlet, Average or Outlet temperature. Enter one of these choices. The ASHRAE Standards 93 and 96 always use Inlet temperature.
First coefficient of efficiency equation for energy conversion (dimensionless). This is the Y-intercept
term.
Second coefficient of efficiency equation for energy conversion (W/m2-K or Btu/h-ft2-F). This is the first order term.
Third coefficient of efficiency equation for energy conversion (W/m2-K2 or Btu/h-ft2-F2). This is the second-order term. If set to zero, a first-order linear correlation is used.
Second coefficient of the incident angle modifier equation. This the first-order term. (There is no Coefficient 1 of Incident Angle Modifier because that number is always 1.0.)
Third coefficient of the incident angle modifier equation. This is the second-order term. If set to zero, a first order linear correlation is used.