How it works

When data is fetched, where it comes from and what happens when Frank Energie's service has a problem.

Update schedule

Data	Fetched	Notes
Prices of today and tomorrow	Every 60 minutes	Every 15 minutes from 12:00 (Dutch time) until tomorrow's electricity prices are there
Monthly costs and invoices 🔑	Together with the prices	When logged in
Daily and monthly usage and costs 🔑	Every 3 hours, every hour while yesterday's gas or electricity is not complete yet (1.8.4)	Groups Daily usage and costs, Monthly usage and costs
Contract price resolution 🔑	Every 6 hours	Group Costs and invoices
Energy dashboard statistics 🔑	Every 3 hours, every hour while yesterday's gas or electricity is not complete yet (1.8.4)	Group Energy dashboard statistics
Price analysis	Every quarter hour, and when new prices arrive	Calculated locally; only the solar forecast is read from another integration

Cost data stays together. Monthly costs, daily and monthly usage and costs, and the statistics are fetched on their own schedules. As soon as one of them receives data for a new day, the integration refreshes the others right away, so they don't show different days because of the schedule. If Frank Energie itself has not published one of them yet, they can still differ for a while; see Known issues.

Between fetches the sensor states still change: at every quarter hour (:00, :15, :30, :45) the price sensors move to the current slot, using the prices already fetched.

Frank Energie usually publishes tomorrow's prices around 13:00. Because of the faster checks after 12:00 they appear in Home Assistant within 15 minutes of publication.

Between 00:00 and 01:00 UTC Frank Energie's service has a daily maintenance window. The integration does not fetch then and keeps showing the prices it has.

Where the prices come from

Entry	Prices
Not logged in	Frank Energie's public prices for the Netherlands, per quarter-hour or per hour (your choice)
Logged in	The prices of your own contract and address, in your contract's resolution. Belgian customers get Belgian prices.

If your account has no prices for electricity or gas on a day (for example without a gas contract), the public prices are used for that part, so the sensors keep working.

Days, time zones and daylight saving

• "Today" and "tomorrow" are Dutch calendar days (Europe/Amsterdam), because that is how the energy market works. This matters only when your Home Assistant is in another time zone.
• A normal day has 96 quarter-hour or 24 hourly electricity prices. On the day the clock goes forward there are 92 or 23, on the day it goes back 100 or 25.
• How times are written in attributes is your choice, see Time zone for price times.

When something goes wrong

Situation	What the integration does
Frank Energie can't be reached or returns an error	Keeps the last prices as long as they still contain upcoming prices, and logs a warning. Tries again at the next update.
No usable prices left	Entities become unavailable until a fetch succeeds.
Monthly costs or invoices fail, prices work	Prices keep updating. The cost and invoice sensors keep their previous value; a warning "Could not fetch …" is logged.
Daily or monthly usage fails	The other one still updates. The failed one keeps its previous value, but last month's numbers are never shown as this month's.
Access token expired	Renewed automatically and saved. You notice nothing.
Renewal refused	Home Assistant asks you to re-authenticate.
Solar forecast integration slow or broken	The price analysis continues without solar after at most 10 seconds.
Home Assistant starts while Frank Energie is down	The integration retries by itself until it succeeds.

Requests to Frank Energie

The integration is careful with Frank Energie's service:

Setup	Requests per day (about)
Not logged in	50 to 60
Logged in, all groups on	135 to 165

The usage, statistics and price resolution requests are only made when their sensor group is on. The first import of the Energy dashboard statistics fetches 30 days with a pause of 5 seconds between days.

Privacy and security

• Your password is not stored. Home Assistant keeps your e-mail address, an access token and a refresh token in its own configuration storage.
• The integration talks only to Frank Energie's service.
• The integration never writes tokens or passwords to the log.
• The diagnostics download removes tokens, e-mail address, address and site reference.
• The integration only reads data. It cannot change your contract or anything else in your account.