Hij @RobbertV !
I”m a new user of your app and liking it very much so far, thanks for the effort!
Just bumped into the issue that cost calculation seems off, in this example the device used 0.41kWh, and the dynamic tariff used at the time was €0.22 per kWh. (I use the value of Homey Energy Variables) That should equate to a cost of €0,09, but it shows €0,04. Am I doing something wrong, or how is the calculation done?
Thanks in advance,
Michiel
Hi Michiel,
It’s a bit hard to determine what is going wrong. It can be the given price value from homey energy or maybe because the duration is over 2 hours (started in hour 1 with price x & ended in hour 2 with price y)
What PowerPrice does (when you update on price change) is a price calculation per different price points, when you finish then we combine the all prices together. To reflect correct usage costs for the duration.
Can you share your flow?
Hi @RobbertV , thanks for the swift reply.
In this case the device only ran for 25 minutes and didn’t enter the new hourly price range.
This is the flow i use, based upon the examples shared by you before.
Hereby the flow, apologies for my poor mspaint skills.
P.S. How do you recommend to summerize the session costs into a grand total, so at the end of the month you know how much energy in total (and costs) one device has used?
Your flow seems correct.
I think that the misperception is with the value of the energy variable for current price value. 0,22 is the placeholder text value. It normally shows the actual value, but in this case not. That is an issue on Homey’s system 
Comparing my own situation; it displays als € 0,22 as well, but when looking at the actual price in the energy tab I’m currently at € 0,25.
I self don’t use the homey provided prices, I make use op PowerByTheHour app. Since the dynamic tariffs weren’t available from homey when creating this.
Hi @RobbertV , thanks for the clarifications, by using the PowerByTheHour dynamic energy prices the calculation seems to be correct. I’ve logged a ticket with Athom to make them aware of the bug (if they weren’t already).
Is your app mainly designed to focus on session cost instead of total cost as well?
I see your app is much more accurate in calculating session kWh compared to the PBTH app, however, PBTH is shipped with a nice overview of cost per day, month, year, etc, which I would like to replicate with your Power Price app.
I’m now purging each session cost to a logical variable per day, and after applying math flows to calculate monthly and yearly cost. I’m not sure if this is the most sensible way of doing this, or if you might have a better way to accomplish this goal. Thanks in advance for any advices!
Since today I see indeed that the homey energy value is indeed way off on what it supposed to be. I unable to set the correct value in Homey energy.
I know noticed since from today onwards I have 15 min price changes (Tibber).
Currently at time of writing Homey does support it, but with incorrect values,
PBTH app is currently broken and the Tibber app only supports hourly rate.
Is your app mainly designed to focus on session cost instead of total cost as well?
Yes the app is mainly focussed on session costs, it is possible to get more data via Homey Insights. However that is not that advanced as what you are looking for.
Depending on your needs you could add more PP virtual devices and let them track usage based on time. F.e. I have a total kWh usage per day running for our house:
But as you already do by usage external flows/apps it’s also possible to achieve that, all depends on the needs.
Does this app use quarterly rates?
Or are you planning to do so?
