$$$ Power pricing $$$

Team, there is an electricity retailer (amberelectric.com.au) that sells power at ~ wholesale + distribution + $15 fixed/month. This is appealing but only as long as you can load shed when required... (eg: pool pump, air con, clothes dryer, hws). Ideally, this will be achieved by receiving a price signal into SHAC and then programming accordingly. Amberelectric have a great help desk and I have received the attached information - a .pdf but am struggling with the next step. I am hoping it distils down to extracting the latest forecast variable rate "wholesalekWHPrice" - which I have highlighted in yellow and using this to update a SHAC user variable. I am thinking that this can be done using a scheduled script operating every 30 minutes. Can anyone help? with thanks....

PS - I could not upload the .json but this link should get to it.. https://mail.google.com/mail/u/0?ui...977457&th=1772885fab80de71&view=att&disp=safe

 

This looks pretty straightforward,
I was unable to get the .Jason as per link, but

Have you tried a sending a http post command from postman or other platform, as per attached 210122 Amberelectric email.PDF, I tried it, it returned a error 502 internal server error... so not sure if I am missing something?

That would be the first step, once the http post command works, the rest is easy...

 

great work Pie Boy. I got it to work via Postman as you can see here. You might have missed putting the postcode into the body of the request. The piece of data I now need to extract is the numerical value at line 709 which is - "1.0109" in this example. I need to write this to a CBusUserParameter every 30 minutes and then do my load management from there. thanks again

 

Cool, yeah i had double quotes on my body message, removed them and then all good, rookie mistake....
Try this, this works for me to receive the complete post response body message and decode the json
you can then access the bits you need within the message table like this
log(message.data.staticPrices)
log(message.data.variablePricesAndRenewables)
are you after specifically the wholesaleKWHPrice value? we will probably need to use some other parameters in the table to find this value, probably a small loop that looks for something inside all the table index then returns a match on the index of the piece we need to look at for the data

eg if we can nail down something specific in the table index that only exists in this piece we can work with that

Code:

function post_request(url, payload)
 require('json')
  ltn12 = require('ltn12')
  http = require ("ssl.https")

  response_body = {}

  res, err = http.request{
    url = url,
    method = 'POST',
    headers =
    {
      ["Accept"] = "*/*",
      ["Content-Type"] = "application/json",
      ["Content-Length"] = #payload
    },
      source = ltn12.source.string(payload),
    sink = ltn12.sink.table(response_body)
 
  }

  if response_body then
   resp = table.concat(response_body)
  resp = json.decode(resp)
    return resp, res, err
  else
    return nil, err
  end
end



message, res, err = post_request('https://api.amberelectric.com.au/prices/listprices', json.encode({postcode = "3232"}))

log(res, err)
log(message)

--log(message.data.staticPrices)
--log(message.data.variablePricesAndRenewables)

 

great - that works fine. The piece of data I need is in line 709. where to now?

 

what exactly are you trying to achieve? will the below achieve this?

here is something to get you started not sure its the most efficient code but without putting to much thought into it here goes, add in below the other code etc

Code:

function find_period(msg, period_tofind)  --"2021-01-27T13:30:00"
 
  for index = 1, #msg.data.variablePricesAndRenewables do
  -- find period and return
    if msg.data.variablePricesAndRenewables[index].period == period_tofind then
    log ('Found period', msg.data.variablePricesAndRenewables[index].period, 'at index', index )
      return msg.data.variablePricesAndRenewables[index].period, index
  end
end

end

local period, index = find_period(message, "2021-01-27T13:30:00")

--now we know the index for the time period we are after, which is individually different from 
all other entries we can get all the data associated with this index like this
 -- message.data.variablePricesAndRenewables[index].period

-- this is as per the amber doc to calculate the formula
log(message.data.staticPrices.E1.totalfixedKWHPrice + message.data.staticPrices.E1.lossFactor *
  message.data.variablePricesAndRenewables[index].wholesaleKWHPrice)

 

thank you again. I played with a variant of what you propose. I found that if I enter the number [50] instead of index, I consistently get the record I am looking for. Here is what I used to get the import price after getting the .json

message, res, err = post_request('https://api.amberelectric.com.au/prices/listprices', json.encode({postcode = "3232"}))

-- Extract Usage price and post to user variable Elec_usage_price (250/23)

staticiprice = (message.data.staticPrices.E1["totalfixedKWHPrice"])
variprice = (message.data.staticPrices.E1["lossFactor"])*(message.data.variablePricesAndRenewables[50]["wholesaleKWHPrice"])
usageprice = staticiprice + variprice

SetUserParam(0, 23, usageprice)

so I am in business - your help appreciated.....

 

Good you got it working for you,

Just so you know, the data you are after at index 50 is Unlikely to 100% always be at that index, it is a possibility under some conditions as amber update its data, its index may move around, as far as I can tell in that table message.data.variablePricesAndRenewables the only thing that is individual in each index element is the time stamp, so to be 100% sure if would use the time stamp to find the index, which is what the code above did,

but hey, whatever works is all good.

 

thanks for the warning - I'll do some more due diligence. I've noticed the row numbers move around a bit as the 30 minute refresh approaches

 

Amberelectric has now released a new API that uses a "GET request" and is way more accurate than the earlier version (as it is now account specific). I've got it working with postman and on the SHAC with the received data looking like this but I cannot get it to isolate the (2) particular values that I need. the first block for "feed-in" tariff and the second block is "general" tariff related and I need the value of "perKwh" in both cases. Any suggestions?

Extract buy/sell prices using new Amber API 27.06.2021 11:08:19
* table:
[1]
* table:
[startTime]
* string: 2021-06-27T01:00:01Z
[renewables]
* number: 16.907
[perKwh]
* number: -12.69729
[endTime]
* string: 2021-06-27T01:30:00Z
[spikeStatus]
* string: none
[estimate]
* bool: true
[spotPerKwh]
* number: 12.14517
[channelType]
* string: feedIn
[type]
* string: CurrentInterval
[date]
* string: 2021-06-27
[nemTime]
* string: 2021-06-27T11:30:00+10:00
[duration]
* number: 30
[2]
* table:
[startTime]
* string: 2021-06-27T01:00:01Z
[renewables]
* number: 16.907
[perKwh]
* number: 20.06872
[endTime]
* string: 2021-06-27T01:30:00Z
[estimate]
* bool: true
[spikeStatus]
* string: none
[tariffInformation]
* table:
[period]
* string: offPeak
[spotPerKwh]
* number: 12.14517
[channelType]
* string: general
[type]
* string: CurrentInterval
>
At this stage, I have tried
<
eprice0 = message.table.[1]["perKwh"] or
eprice0 = message.data.[1].[perKwh]
>
and lots of other permutations and combinations but without success - I am just guessing and need some knowledgable input please.
cheers

 

solved it myself (for once)

needed some brackets but here's the answer for others

eprice0 = (message[1]["perKwh"])