If we have to go to 15 minutes data then I have to added 3 variables per hour to keep the 8 hour price list.
That’s needed to get then on the dashboard.
How to get them in the app for the virtual device is an equal thing.
Getting them out of the JSON file is also a point to notice.
An good reason for Homey to come with variable arrays
Some info.
That 15 minute mark is not new in the industrie.
Many years ago there where special contracten for the max kWh that may used in the 15 minutes.
Were very precise meter to checked that.
No bug. It just takes the lowest and highest 4 hours in the entire range. It is just intended as a visual aid to see where the lowest/highest prices are. Nothing more…
I’m relatively new to programming and currently making some advanced flows with Homey.
I just switched to a dynamic energy contract where I would like to benefit from the low energy prices or when solar energy is available e.g. to charge my car.
I use the PBTH app in homey for the prices and would like to use the forecasted price data to either charge the car over night or not depending if I need it the next day and/or if solar energy may be available today/tomorrow.
I use the “time required till full car battery” (based on current battery % and average charge load) as a variable and would like to get as an output the lowest average cost for the required time + at what timeslot. I could then make a trigger/notification if i would like to proceed with proposed plan or delay charge till next day (where this calculation repeats).
How do I get the lowest average cost (for the required charge time) + timeslot?
I currently use the card “average price coming [Time required full battery] is lowest for [xx hrs] before 8:00hr”. This does not allow to look in the future and use this as a trigger (if average is above a certain threshold or if weather forecast for tomorrow is looking sunny)
I have found the card to obtain the next day electricity prices as a text/JSON but am not familiair on how to use this.
Hi @R_Ligtenberg ,
Use one of the cards
Just calculate each hour the remaining hours you need to charge and probably the hours that are left until you need the car again.
So you don’t have to deal with a list of prices.
_
Furthermore, you usually also have this factor as well:
When you want to start driving at X o’clock, then regardless of the most advantageous hour and/or PV results, the car should eventually be charged at some point anyway, depending on the current battery level and the desired level.
Here is a “departure time dependent latest time to start charging” flow set:
I am using the first card currenlty but it is a conditional card which activates once the average price level is lowest for specified number of hours. Usually this would be during night time as prices are lower. I want to get notified in the evening already whether the night lowest average price (for remaining charge time) is higher than a pre-set value. That would give me the option to choose dependent if I do not require the car for the next day(s).
It should then work kind of similar to the Tibber app smart charging scheme where you provide the time and days in the week when you need the car to be ready. Tibber then looks at cheapest time to charge the battery based on the boundary conditions.
Is there a card or function that I could use to trigger an early heads-up?
Dynamic prices are forecasted 24hrs but in the flowcard tags I only get to current hr+8 which is not sufficient if I want to have it backcalculated automatically and notify me in advance. I’m not sure if cheapest hour and lowest price are the best parameters to use in this case. I would rather look at cheapest overall for charge time required. Basically an average lowest cost for total charging duration (avoiding start/stops in case of eratic price behavior).
The optimum timing to start charging would actually turn out differently using averages vs using cheapest hr/price especially since cheapest hr/price is preceded by an initial decline from a higher price. At its lowest point the price may already start to climb again shortly after which would have started the charge command too late.
You are right, the limitation to the next 8 hours is a bit of deficit of the App. You might help a bit with using lowest nth price of today and tomorow, if the remaining time is much more than the next 8 hrs-prices, but it still won#t be perfect. I won’t propose average prices.
To me in praxis the 8 hrs limitation does not harm very much, but if you see such a price effect, you can intervene by de-activating and activating the flow or adding a variable that the flow would be only recongised, if the remaining time is 8, 9 or whatever hrs to that time.
The other way would be discuss via github PTBH, if it is possible to lift this limitation - or you really ask for how you can calculate the nth lowest prices out of the json result by an app or via Homey Script. I would like that solution, too.
best regards
Yeah the tags end at +8h, but I wasn’t referring to that; like i wrote
Like DirkH already wrote, I also think the card with “when price becomes one of Y lowest in the X hours before [time]” basically can do the job, as trigger; it is not limited to midnight or just +8 hours if I’m informed well.
So, this is possible to use as action trigger: when price becomes one of 2 lowest in the 3 hours before 07:00
When you’d like to get informed at, say, 6PM today, about the cheapest hours before tomorrow 7AM, I"m afraid you’ll have to use the JSON & homeyscript.
Or,
You can kindly request for a THEN flowcard, like, “Return the X hours when price becomes one of X lowest before [time]”
Hi,
I’m trying to createa advanced to to use Price now trigger but for some reason I just cant get it to work. Here my testing flow, any ideas what is wrong. Nothing happens.
As you don’t mention for how long you’ve waited, and if the price got < 0.15 in the meantime:
Do realize the flow will only trigger if the price was below 0.15 first.
Now the flow has been active from the yesterday and the price has been lower in some hours but the flow hasn’t started. Tried also higher card with low € settings but no luck eather.
