Nordpoll in to OH3

[Mads_Bloch]

This rule fetch the data from Nordpool

Can't get InfluxDB data to Grafana when seetting my own timestamp

Hi, I’m polling electricity prices for the coming day from an API. I store these prices in my InfluxDB, but since it’s in the future I need to add my own timestamp and therefore I use the InfluxDB API. Finally I use Grafana to draw graphs. However, for some reason Grafana is not able to retrieve any data. I have one raspberry pi 3b running Openhab 3.1 (latest stable release) and influxDB and another raspberry pi 3b running Grafana, both running Raspbian Buster. I have other Items that are stor…

Im trying to use the method, I can see it fetched data just fine but im having trouble changing dot to comma.

Thanks Mads

[Wolfgang_S]

@jesper_landtved

I have installed Exec binding in OH3 now.
Is it true that I need a Things file, Items and a Rules to get the value ?.

Although I stated earlier to use the exec binding it may be easier to use executeComandLine.
You need to have e.g. an item that can be used to display the current value.
Besides that just a rule is required. A DSL rule could look like:

rule "Get the price"
when
        Time cron "0 0 * * * ?" //run every hour
then
        var Number tmp = executeCommandLine( Duration.ofSeconds(5), "/path/to/scripts.sh" )
        Price.postUpdate( tmp )
end

This would use a cron entry which runs triggers the execution every hour.
Path to script needs to be replace with the correct path of the script containing the wget/curl command etc.

[Wolfgang_S]

@Mads_Bloch

im having trouble changing dot to comma

Using the code example that I provided you could use sed to replace dot with comma ( the example below uses two sed commands as a comma is already provided; first one changes , to .; second one . to , ) :

wget --quiet -O - 'https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=' | jq '.data.Rows[0].Columns[0].Value' | sed -e 's/,/./' | sed -e 's/\./,/'

[jesper_landtved]

i have tried the following:

rule “Get the price”
when
Item Renew_price changed
then
var Number tmp = executeCommandLine( Duration.ofSeconds(5), “wget --quiet -O - ‘https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=’ | jq ‘.data.Rows[0].Columns[0].Value’” )
Electricity_price.postUpdate( tmp )
end

Number Electricity_price “Electricity_price [%.2f]” (GF_Office)
Switch Renew_price “Renew_price” (GF_Office)

But i get an error in log view:
Failed to execute commandLine ‘[wget --quiet -O - ‘https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=’ | jq ‘.data.Rows[0].Columns[0].Value’]’

[Wolfgang_S]

You can use a ( single ) linux command in executeCommandLine but arguments have to be separated into single arguments of executeCommandLine. They have to be separated by commas.
executeCommandLine does not support the pipe ( | ) to be part of the command that is to be used.
This is why you need to create a script in the linux environment which contains all of your commands ( the complete piped command wget …jq …; it even would be possible to add more lines there ).
The use just that script as argument in executeCommandLine as written in my earlier post.

The script content will look like:

#!/bin/sh
wget --quiet -O - 'https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=' | jq '.data.Rows[0].Columns[0].Value'

Make it readable and executable:

chmod ugo+rx /path/to/your/script

[hafniumzinc (T)]

As a slight aside, the URL https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate= does not produce valid JSON so the earlier mentioned method of using the HTTP binding together with the JSONPATH transformation would likely not work.

Looks like @Wolfgang_S method is the way to go here.

I take that back. The following works fine:

UID: http:url:nordpool
label: HTTP URL Thing
thingTypeUID: http:url
configuration:
  authMode: BASIC
  ignoreSSLErrors: false
  baseURL: https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=
  delay: 0
  stateMethod: GET
  refresh: 60
  commandMethod: GET
  timeout: 3000
  bufferSize: 2048
channels:
  - id: value
    channelTypeUID: http:string
    label: Value
    description: ""
    configuration:
      stateTransformation: JSONPATH:$.data.Rows[0].Columns[0].Value

To get a usable Number type Item without messing about with files, you can use the Math Transformation Service provided by the SmartHomeJ repository, and then add a DIVIDE profile to the link between the Thing Channel and the Item.

UID: http:url:nordpool
label: HTTP URL Thing
thingTypeUID: http:url
configuration:
  authMode: BASIC
  ignoreSSLErrors: false
  baseURL: https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=
  delay: 0
  stateMethod: GET
  refresh: 60
  commandMethod: GET
  timeout: 3000
  bufferSize: 2048
channels:
  - id: value
    channelTypeUID: http:string
    label: Value
    description: null
    configuration:
      stateTransformation: JSONPATH:$.data.Rows[0].Columns[0].Value
  - id: value2
    channelTypeUID: http:number
    label: Value2
    description: null
    configuration:
      stateTransformation: JSONPATH:$.data.Rows[0].Columns[0].Value

[tnemrap (Michael Parment)]

How do i find on what page SE3 is on?

[jesper_landtved]

i think this is it.
https://www.nordpoolgroup.com/api/marketdata/page/29?currency=EUR&endDate=

[tnemrap (Michael Parment)]

This works well.
I now use the time prices to decide if i should start equipment e.g. poolheater.

[jesper_landtved]

Has NordPool changed their setup on the page I’m pulling data from?. I no longer get data from the site into OH3. it worked fine until now but not anymore.

[Wolfgang_S]

@jesper_landtved

it worked fine until now but not anymore

the curl example still seems to work.

[OMR (Ole Morten Rønning)]

Here is an alternative method: GitHub - kipe/nordpool: Python library for fetching Nord Pool spot prices.

[jesper_landtved]

does this commando still work? I get no value in Putty when I try it.

[Wolfgang_S]

@jesper_landtved

oes this commando still work?

which one ? Just tried following example and it seems to work
script contains:

#!/bin/sh
wget --quiet -O - 'https://www.nordpoolgroup.com/api/marketdata/page/47?currency=EUR&endDate=' | jq '.data.Rows[0].Columns[0].Value'

Executed on command line:

sh /tmp/a.sh

then returns:

"103,37"

[jesper_landtved]

it seems that it was a mistake in how I had set up static ip on my raspberry that was to blame for the problems. the commands and prices are now up and running again, thanks for the feedback.

[somy (mai)]

Hi all, I managed to set up the HTTP binding to poll the values into OpenHAB, however I have a bit difficulty to convert the number with “,” as decimal separator to float numbers. Any suggestion what to do? Many thanks

Below is my things:

Thing http:url:NordPool "NordPool EL Price" [
	baseURL="https://www.nordpoolgroup.com/api/marketdata/page/41?currency=DKK",
	refresh=1000] {
		Channels:
			Type string : Price "Price" [stateTransformation="JSONPATH:$.data.Rows[0].Columns[1].Value" ]
}

And item:

Number    NordPoolELPricePrice    "Price"           (gNordPool)    {channel="http:url:NordPool:Price"[profile="transform:JS", function="nordPoolPrice.js"]}

As you can see I tried to use transform profile which doesn’t seem to take any effect.

[Anders_Saederup (Anders Sæderup)]

hi, I know it’s a bit of an old thread, but how do you transfer the data to openhab, I’ve tried using the function node that was created as an example here node-red-contrib-nordpool-api-plus (node) - Node-RED
and then from that directly in to a number item, which also results in transferring the entire series of data to the same item. do you do it the same way or do use another approach?

Anders

[SHO (Steen Holm)]

Hi Anders, I was struggling to get openHAB or Influx to show a graph with data in the future, so I ended up with just created a page with web link to elspotpris.dk.
Only number I needed in openHAB is the Spot price including tax and vat. Big Timer change between low and high tax depending on the hour, each hour request to Nordpool, this also set time now to global.set, chart data add the tax and vat, a change switch filter out the spot price now and update the item from openHAB

Nordpool to openHAB.json (14.6 KB)

[Anders_Saederup (Anders Sæderup)]

thank you, it works well

[masipila (Markus Sipilä)]

Here’s a solution which fetches the prices from Entso-E Transparency platform

Control a water heater and ground source heat pump based on cheap hours of spot priced electricity

Update on Feb 22, 2024. The solution discussed in this thread evolved to a NPM package openhab-spot-price-optimizer. [image] The blue area in the figure above represents the spot prices. The yellow bars indicate when the heating of the house will be ON and the red bars indicate when the water boiler will be ON to heat domestic hot water. The solution can be used with any devices you can control with openHAB. Installation instructions and full documentation with examples can be found at Home…