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element nameterrain
defined inhttp://solargis.info/schema/common-geo.xsd
descriptionGround terrain characterized by altitude, terrain slope and terrain azimuth. This element can affect the self shading of a fixed-angle PV array.
contentnone
@elevationoptional, meters above the mean see level. If missing, the value will be taken from SRTM terrain database
@azimuthoptional, orientation of tilted terrain in degrees, 0 for North, 180 for South, clockwise, default is 180, has no meaning for a flat terrain
@tiltoptional, slope tilt of terrain in degrees, 0 for flat ground, 90 for vertical surface, default is 0 (flat)

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element namehorizon
defined inhttp://solargis.info/schema/common-geo.xsd
descriptionUser can provide custom skyline for expressing distant or close obstruction features (hills, trees, buildings, poles, etc.)
contentString of this form: space-delimited list of float number pairs [azimuth in degrees:0-360]:[horizon height in degrees:0-90], Example: "<geo:horizon>0:3.6 123:5.6 359:6</geo:horizon>"

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element namegeometry
defined inhttp://solargis.info/schema/common-pv.xsd
description

Parametrization of PV system mounting type used for calculating GTI and PVOUT. If this element is missing and GTI/PVOUT is requested, flat-lying PV panels are considered (GTI=GHI). Examples:

<pv:geometry xsi:type="pv:GeometryFixedOneAngle" azimuth="180" tilt="25"/>

<pv:geometry xsi:type="pv:GeometryOneAxisHorizontalNS" rotationLimitEast="-90" rotationLimitWest="90" backTracking="true"/>

<pv:geometry xsi:type="pv:GeometryOneAxisInclinedNS" axisTilt="30" rotationLimitEast="-90" rotationLimitWest="90" backTracking="true"/>

<pv:geometry xsi:type="pv:GeometryOneAxisVertical" tilt="25" rotationLimitEast="-180" rotationLimitWest="180" backTracking="true"/>

<pv:geometry xsi:type="pv:GeometryTwoAxisAstronomical" rotationLimitEast="-180" rotationLimitWest="180" tiltLimitMin="10" tiltLimitMax="60" backTracking="true"/>

contentnone
@type*

required, concrete type of given geometry. Use one from GeometryFixedOneAngle, GeometryOneAxisHorizontalNS, GeometryOneAxisInclinedNS, GeometryOneAxisVertical, GeometryTwoAxisAstronomical, see table below

@azimuthorientation of tilted panel surface in degrees, defined as true geographical azimuth (0:north, 90:east, 180:south, 270:west, 360:north), default is 180 deg., the attribute is not defined for a horizontal surface, required only for 'GeometryFixedOneAngle' type
@tilttilt of panel surface in degrees range (0, 90), 0=horizontal, 90=vertical surface, required for 'GeometryFixedOneAngle' and 'GeometryOneAxisVertical' types
@axisTilt

optional, tilt of rotating inclined axis in degrees, 0 = horizontal, 90 = vertical axis, only considered for 'GeometryOneAxisInclinedNS',

WARNING: if this attribute is missing, the value defaults to 30 degree.

@rotationLimitEast

optional, default is the unlimited motion in the range (-180, 180), used for all trackers. The general rule is: negative value is used for the east side, positive for the west side, the same rule applies for both hemispheres). The meaning is slightly different for different type of trackers:

GeometryOneAxisHorizontalNS: rotation limits are defined as tilt of tracker table relative to its central position (which is horizontal=0 deg.), both limits are typically symmetric, e.g., rotationLimitEast=-50, rotationLimitWest=50

GeometryOneAxisInclinedNS: rotation limits are defined as tilt of tracker table relative to its central position (in this case the inclined plane defined by axisTilt attribute), both limits are typically symmetric, e.g., rotationLimitEast=-50, rotationLimitWest=50

GeometryOneAxisVertical: rotation limits are defined relative to 0 deg. (initial tracker position regardless of hemisphere), default range from -180 to 180 deg (-90 deg. east and +90 deg. west)

GeometryTwoAxisAstronomical: definition (for vertical axis) is the same as with GeometryOneAxisVertical tracker

@rotationLimitWestoptional, westing motion limit, described above
@tiltLimitMinoptional, only used with the horizontal axis of 'GeometryTwoAxisAstronomical' tracker. Limit is defined in the range of degrees (-90, +90), relative to the horizontal position of the tracking surface (0 deg.). Example: tiltLimitMin="0" tiltLimitMax="60", the tracker follows the sun elevation in the range from horizontal position to 60 degree of tilt.
@tiltLimitMaxoptional, max tilt of the tracking surface, described above
@backTrackingoptional boolean value, default is 'false' - tracker moves freely regardless of the neighbors, value 'true' - tracker moves in the way it avoids shading from neighboring tracker constructions.

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element namesystem
defined inhttp://solargis.info/schema/common-pv.xsd
description

Parametrization of the PV system. Required for simulating PVOUT parameter.

contentrequired one <module> element, required one <inverter> element, required one <losses> element, optional one <topology> element,
@installedPower*

required float value (greater than zero). Total installed DC power of the PV system in kilowatts-peak (kWp). The total PV system rating consists of a summation of the panel ratings measured in STC.

@installationTypeoptional, use one from FREE_STANDING (default), ROOF_MOUNTED, BUILDING_INTEGRATED. This property of the PV system helps to estimate how modules are cooled by air. For sloped roof with PV modules on rails tilted at the same angle as the roof choose 'ROOF_MOUNTED' value. For PV modules incorporated into building facade choose 'BUILDING_INTEGRATED' value. This option is considered as the worst ventilated. As the best ventilated option is considered 'FREE_STANDING' installation. This typically means stand-alone installation on tilted racks anchored into the ground. Also choose this option if a PV system is installed on a flat roof.
@dateStartup

optional string formatted as "yyyy-mm-dd" (example 2015-01-01). Start-up date of the PV system (unpacking of modules). This parameter is used for calculation of degradation of modules caused by aging. If omitted, the degradation is not taken into account.

@selfShading

optional, default is 'false'. The parameter affects PV power calculation for 'GeometryFixedOneAngle' geometry, then 'GeometryOneAxisInclinedNS' and 'GeometryOneAxisHorizontalNS' trackers if backTracking="false". When 'selfShading' is switched on, the simulated PV power is typically lower comparing to standalone PV construction not affected by shading from its neighbors. With trackers, always switch off 'backTracking' attribute, because the back tracking avoids self-shading.

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element namemodule
defined inhttp://solargis.info/schema/common-pv.xsd
description

Parametrization of the PV system modules. Required for simulating PVOUT parameter. All modules in one PV system are considered of the same type.

contentoptional one <degradation> element, optional one <degradationFirstYear> element, optional one <nominalOperatingCellTemp> element, optional one <PmaxCoeff> element
@type*

required. Enumerated codes for materials used in PV modules. Use 'CSI' for crystalline silicon, 'ASI' for amorphous silicon, 'CDTE' for cadmium telluride, 'CIS' for copper indium selenide. For the estimate of module's surface reflectance we use an approach described here.

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element namedegradation
defined inhttp://solargis.info/schema/common-pv.xsd
description

Estimated annual degradation [%] of rated output power of PV modules. This element is only considered if "dateStartup" attribute of PV system is present. If the element is missing, degradation defaults to 0.5%/year.

contentrequired, float number in the range (0, 100), %

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element namedegradationFirstYear
defined inhttp://solargis.info/schema/common-pv.xsd
description

Estimated annual degradation [%] of rated output power of PV modules in the first year of operation. If the element is missing, degradation defaults to 0.8%/year.

contentrequired, float number in the range (0, 100), %

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element namenominalOperatingCellTemp
defined inhttp://solargis.info/schema/common-pv.xsd
description

Normal operating cell temperature (NOCT). Float value of the temperature in degrees Celsius of a free standing PV module exposed to irradiance of 800 W/m2 in the ambient air temperature of 20°C and wind speed of 1 m/s. The value is given by manufacturer and for ventilated free-standing PV systems only. If the element is missing, the NOCT value defaults to (based on technology):

CSI=46°C
ASI=44°C
CDTE=45°C
CIS=47°C

contentrequired, float number in degrees Celsius

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element namePmaxCoeff
defined inhttp://solargis.info/schema/common-pv.xsd
description

Negative percent float value representing the change of PV panel output power for temperatures other than 25°C (decrease of output power with raising temperature). This property is given at the STC by manufacturer. If the element is missing, the PmaxCoeff value defaults to (based on technology):

CSI=-0.438%/°C
ASI=-0.18%/°C
CDTE=-0.297%/°C
CIS=-0.36%/°C

contentrequired, float number, percent per degree Celsius (%/°C)

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element nameefficiency
defined inhttp://solargis.info/schema/common-pv.xsd
description

Efficiency of the inverter. If the element is missing, the efficiency is given as a constant value of 97.5%.

@type*required, concrete type of how efficiency of the inverter should be modeled. Use one from EfficiencyConstant, EfficiencyCurve
content

required, based on type:

EfficiencyConstant:

float number, [%]. Value of inverter's efficency known as Euro or CEC (California Energy Commission) efficiency. This value is a calculated weighted efficiency given by manufacturer. It gives a simplified picture about an inverter's, in fact non-linear, performance. Valid range of this value is typically in the range 70%-100%. For better results, it is recommended to provide inverter's efficiency curve.

EfficiencyCurve:

text value, pairs of kW:percent. Efficiency of inverter is of non-linear nature, so it can be described as simplified curve defined as list of data points. Data point on the curve is defined by coordinates, where the x coordinate is absolute float value of input power in kilowatts (kW) and y coordinate is percent float value of the corresponding inverter's efficiency (%). This parameter accepts string value of this pattern: 'x1:y1 x2:y2 x3:y3 xn:yn'. A dot should be used as decimal separator, white space as a pair delimiter and colon as x:y delimiter. We assume the last point determines the maximum input power of the inverter (with corresponding efficiency). Example of an efficiency curve with the maximum input power of 3 kW is:

<pv:efficiency xsi:type="pv:EfficiencyCurve" dataPairs="0:85.6 0.5:96.2 1:98 1.5:97 2:97 2.5:96 3.0:96"/>

It is assumed, that one efficiency curve is valid for all inverters of the PV system (their powers are summed).

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element namelimitationACPower
defined inhttp://solargis.info/schema/common-pv.xsd
description

Maximum power accepted by the inverter as AC output. Higher power values are 'clipped'. Clipping refers to the situation where the AC power output of an inverter is limited due to the peak rating of the inverter (the parameter value in kW), even though the additional power may still be available from the solar modules. If you have power factor (PF) and AC limit in kVA available, use this formula: PF * AC_limit_kVA = kW, to obtain the value of this parameter.

No default.


contentrequired, float number, kilowatts [kW]

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element namelosses
defined inhttp://solargis.info/schema/common-pv.xsd
description

Estimation of various PV losses.

contentoptional one <acLosses> element, optional one <dcLosses> element

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element namedcLosses
defined inhttp://solargis.info/schema/common-pv.xsd
description

Estimation of power losses on the DC side. If the element is missing, the specific DC losses are estimated by default as:

snowPolution: 2.5%

cables: 2.0%

mismatch: 1.0%

contentnone
@snowPollutionannual value of estimated dirt and snow losses [%]
@monthlySnowPollution

Distribution of the 'snowPollution' attribute value into 12 monthly average values. Value of the parameter must consist of 12 percent float values delimited by white space. If this parameter is present, it takes precedence over 'snowPollution' attribute. Example:

<pv:dcLosses cables="0.2" mismatch="0.3" monthlySnowPollution="5 5.2 3 1 1 1 1 1 1 1 2 4"/>

@cablesannual value of estimated DC cabling losses [%]
@mismatchannual value of estimated DC mismatch losses [%]

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element nameacLosses
defined inhttp://solargis.info/schema/common-pv.xsd
description

Estimation of power losses on the AC side. If the element is missing, the specific AC losses are estimated by default as:

transformer: 1.0%

cables: 0.5%

contentnone
@transformerannual value of estimated transformer losses [%]
@cablesannual value of estimated AC cabling losses [%]

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element nametopology
defined inhttp://solargis.info/schema/common-pv.xsd
description

The element is for defining PV plant layout on the ground. The reason is to provide inputs for calculation of self-shading impact on PV power (e.g., how close to each other are PV constructions).

contentnone
@type*XML element type, required, concrete type of how topology should be modeled. Use one from TopologyRow (applies for the 'GeometryFixedOneAngle' geometry), TopologyColumn (use for all trackers). It is assumed trackers are spaced equally in both directions (rows and columns) creating a regular grid.
@relativeSpacing

required, unitless ratio. The attribute specifies the ratio of distance between the neighboring PV table legs and PV table width. Direction of the distance depends on whether topology is specified as TopologyRow or TopologyColumn. See picture below how to calculate the value.

@typeoptional. This parameter estimates a magnitude of loss of PV power when modules are shaded or semi-shaded. The effect depends on wiring interconnections within a module. Shading influence ranges from 0% (no influence) to 100% (full influence) and it is classified into following categories (based on the influence value):

PROPORTIONAL = 20%
UNPROPORTIONAL_1 = 40%
UNPROPORTIONAL_2 = 60%
UNPROPORTIONAL_3 = 80%
When this attribute is missing, the self-shading influence is estimated to 5%.

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