Nordpooli boiler

 // https://elspotcontrol.netlify.app/
// This version: 18.1.2023


// Find the time from time period starting here and lasting this many hours
let period_start = 23;
let period_length = 22;

// If period_start refers to this hour today, this should be 0. If the it is tomorrow, it must be 1.
let period_day = 0;

// Request cheapest hours for this length. Set this to typical length needed for f. ex. water heater.
let needed_length = 3;

// Turn off after this many hours. May be good to keep this longer than needed_length, as
// f. ex. heating water may sometimes take longer
let turn_off_hours = 5;

// If fetching prices fails, use these schedules. Crontab format
let defaultstart = "0 1 2 * * SUN,MON,TUE,WED,THU,FRI,SAT";
let defaultend = "0 1 7 * * SUN,MON,TUE,WED,THU,FRI,SAT";

// Maximum average hourly price. If hourly price is higher than this, do not turn switch on!
// This setting still sets the schedule, but sets switch off both on start and stop.
// If you want, you can manually then turn the scheduled time on.
// By default, and if you do not want to uset this, set this very high.
// The price is EUR per megawatthour, not including taxes! So eg. for a price of 50c/kWH, use 500
let max_avg_price = 999999;

// Crontab for running this script. Good to keep this way
// This means that this script is run at random moment during the first 15 minutes after 18.00
// Random timing is used so that all clients wouldn't be polling the server exactly at same time
let minrand = JSON.stringify(Math.floor(Math.random() * 15));
let secrand = JSON.stringify(Math.floor(Math.random() * 60));
let script_schedule = secrand+" "+minrand+" "+"18 * * SUN,MON,TUE,WED,THU,FRI,SAT";
print(script_schedule);


// Number for this script. If this doesn't work (as in earlier versions), get it from this url (use your own ip) http://192.168.68.128/rpc/Script.List
let script_number = Shelly.getCurrentScriptId();



// You can check the schedules here (use your own ip) http://192.168.68.128/rpc/Schedule.List

function maybe_over_midnight(hour) {
  if (hour>24) {
    return hour-24;
  }
  else {
    return hour;
  }
}


function find_cheapest(result) {
    print("HTTP response is", result);
    if (result === null) {
        updateSchedules(defaultstart, defaultend, true);
    }
    else {
        print("Finding cheapest hours");

        let prices = JSON.parse(result.body);

        let hourly_prices = prices["hourly_prices"];
        let num = 0;

        let cheapest_period = {};
        cheapest_period["period_price"] = 999999999999;

        for (let i = period_start; i < period_start + period_length; i++) {

            let hour = i;

            if (i >= 24) {
                hour = hour - 24;
                period_day = 1;
            }

            let hr = JSON.stringify(period_day)+"."+JSON.stringify(hour);

            hourly_prices[hr]["period_price"] = 0;

            for (let a = 0; a < needed_length; a++) {
                let ah = hour + a;
                let ahday=period_day;
                if (ah >= 24) { ah = ah - 24; ahday=1; }
                let ahh = JSON.stringify(ahday)+"."+JSON.stringify(ah);
                hourly_prices[hr]["period_price"] = hourly_prices[hr]["period_price"] + hourly_prices[ahh]["price"];
            }

            if (hourly_prices[hr]["period_price"] < cheapest_period["period_price"]) {
                cheapest_period = hourly_prices[hr];
                cheapest_period["hour"] = hour;
                print("cheapest");
            }

            print(hour, hourly_prices[hr]["time"], hourly_prices[hr]["price"], hourly_prices[hr]["period_price"]);




        }
        print("Cheapest hour", cheapest_period["time"], cheapest_period["period_price"], "average",
            cheapest_period["period_price"] / needed_length)

        // Set the timers
        let timespec = "0 0 " + JSON.stringify(cheapest_period["hour"]) + " * * SUN,MON,TUE,WED,THU,FRI,SAT";
        let offspec = "0 0 " + JSON.stringify(maybe_over_midnight(cheapest_period["hour"] + turn_off_hours)) + " * * SUN,MON,TUE,WED,THU,FRI,SAT";

        // Check the avg price if the switch should or should not be turned on.
        let turn_on=true;

        if (cheapest_period["period_price"] / needed_length > max_avg_price) {
          print("Turning off!");
          turn_on=false;
        }

        updateSchedules(timespec, offspec, turn_on);
    }
}


function updateSchedules(timespec, offspec, turn_on) {

    print(Shelly.call("Schedule.DeleteAll"));




    print(Shelly.call("Schedule.Create", {
        "id": 0, "enable": true, "timespec": timespec,
        "calls": [{
            "method": "Switch.Set",
            "params": {
                id: 0,
                "on": turn_on
            }
        }]
    }
    ));


    print(Shelly.call("Schedule.Create", {
        "id": 0, "enable": true, "timespec": offspec,
        "calls": [{
            "method": "Switch.Set",
            "params": {
                id: 0,
                "on": false
            }
        }]
    }
    ));

    // Schedule for the script itself
    print(Shelly.call("Schedule.create", {
        "id": 3, "enable": true, "timespec": script_schedule,
        "calls": [{
            "method": "Script.start",
            "params": {
                "id": script_number
            }
        }]
    }));

    //Stop this script in one minute from now
    Timer.set(60 * 1000, false, function () {
        print("Stopping the script");
        Shelly.call("Script.stop", { "id": script_number })
    });

}


function updateTimer() {
    print("Starting, fetching hourly prices");
    Shelly.call("HTTP.GET", { url: "https://elspotcontrol.netlify.app/spotprices-v01-EE.json", timeout:60, ssl_ca:"*"}, find_cheapest);
}


updateTimer();