hours_needed
The number: this many cheap hours the plant needs now.
Hours · EMS · Storage
Hours Demand: how many cheap hours does your EMS need?
Hours tells your energy manager how many cheap grid hours the battery needs right now — from state of charge, household load and PV — and at which clock times.
Example: cloudy today, sun tomorrow
The battery sits at 28%. Overnight the house still needs power. PV is weak today, strong tomorrow midday. Hours fills only the gap — not the whole battery.
- Battery (SOC)
- 28%
- Load left until tomorrow
- 8 kWh
- PV tomorrow midday
- 22 kWh
- Grid hours now
- 3 hours
Concrete clock times the EMS can apply:
01:00
02:00
03:00
Illustrative example, not live data. Real values need a site profile and API key.
How Hours calculates
Three inputs stop the EMS from guessing.
-
Know the state
How full is the battery, what will the house still use, what will PV add?
-
Find the gap
Hours covers until the next good sun — not the whole week’s load.
-
Pick cheap hours
As many grid hours as needed, at the cheapest spot-price times.
What your EMS gets back
One POST /v1/decision/hours-demand call returns the decision, not a raw chart.
charge_hours
The timestamps and prices — so the optimizer does not have to search.
Until PV carries
The horizon ends at the next good sun, not at “charge the whole week”.
In plain words
Do I need a programmer for this?
Loxone has ready PicoC guides. If you build an EMS, you fetch the number over REST. A free Community account is enough to try it.
How is this different from cheap-hour windows?
Windows says which N hours are cheapest. Hours says how many hours this plant needs now, because storage, load and PV look like this.
Are the example numbers live data?
No. They explain the logic. Live values need a plant profile in the portal and an API key. The technical spec is in Docs.
Put Hours into your EMS
Community to try it. Spec and Loxone guide to install. PV Forecast supplies the sun.