Sample integration of WebSolarLog into openhab

For those that have no direct connection to their solar System or PVOutput - you might consider to check if WebSolarLog.com can support your device. The devices can be found on the WebSolar Log Web Page.

I have succesfully integrated this for my Diehl Solar system and can get the live data via http binding and a small transformation into OH to react on energy production/ sun.

Steps to take:

• check if websolarlog supports your solar/ energy device
• install the same on either the same device or on a seperate one. Currently experimenting with it - a seperate PI would be performance wise better to suite
• after installation done use the API from websolarlog to take a look on the desired data: 'http:///websolarlog/json2xml.php?url=/websolarlog/api.php/Live?url=/websolarlog/api.php/Live'

With this you should be able to see a XML File with the relevant information needed. The XML transfromation PHP should be in the current release - if not a guidance to download can be downloaded here: WebSolarBugTracker

• now you need to create a transformation file in the transform directory of openhab:

wsl_pv_GP.xsl:

<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
        
        <xsl:output indent="yes" method="xml" encoding="UTF-8" omit-xml-declaration="yes" />

        <xsl:template match="/">
						    <xsl:for-each select="html/body/div/tr/td">
				    			<xsl:if test="Power:">
						      <xsl:value-of select="span name="/>
						    </xsl:if>
						    </xsl:for-each>
        </xsl:template>

</xsl:stylesheet> 

OH items

Number DiehlWtemp	"Diehl W  [%.3f]"	{ http="<[http://<yourWSLIP>/websolarlog/json2xml.php?url=<yourWSLIP>/websolarlog/api.php/Live?url=<yourWSLIP>/websolarlog/api.php/Live:60000:XSLT(wsl_pv_GP.xsl)]" }
Number DiehlKW     "Diehl KW [%.3f kW]"

I then transformed the same by a rule into kW.

Sample Rules

Created to react on the kW generated to close down some shutters:

// Calculate based on Input from Script the kW
rule "Calc KW"
when
   Item DiehlW received update
then
   {
    var diehlW  = DiehlW.state as DecimalType
    var diehlKW = (diehlW / 1000)
    postUpdate(DiehlKW, diehlKW)
   }
end
  
// Calculate the average kW from last 90 minutes
rule "Calc SolarAverage"
when
   Item DiehlKW received update
then
   var diehlAV = DiehlKW.averageSince(now.minusMinutes(90)) as DecimalType
   postUpdate(DiehlAV, diehlAV)
end
  
// Activate the Solar actions based on an average kW above 1.8
rule "Activate SunAuto based on SolarAverage"
when
   Item DiehlAV received update
then
   if (DiehlAV.state >= 1.8)
    {
     sendCommand(SunAuto, ON)
    }
   else sendCommand(SunAuto, OFF)
end

// Activate shutter down when SunAuto.state is ON between 11-17 every 15 minutes
rule "Sonnenschutz Automatisch"
when
   Time cron "0 */15 11-17 * * ?"
then
   if(SunAuto.state==ON){
     postUpdate(SunAutoActive, ON)
     sendCommand(Shutter_DG_West, DOWN)
     Thread::sleep(15000)
     sendCommand(Shutter_DG_West, STOP)
   }
   else if(SunAuto.state==OFF){
        if (SunAutoActive.state==ON){
            postUpdate(SunAutoActive, OFF)
            sendCommand(Shutter_DG_West, UP)
        }
   }
end

Have fun!
Karsten