The guaranteed SoC requirement is exactly what I was looking for, so I’ll use HomeFlux for the 30% minimum at 06:30 rather than building a separate guard around it.
Good point on the Hybrid EMS fallback as well. I’ll keep that outside HomeFlux as a small independent Homey watchdog whose only job is to return the SMA to its native EMS if HomeFlux becomes unavailable. That fits nicely with the 802/803 handover I already tested.
I’m away now, so I’ll leave everything unchanged and pick up the Hybrid EMS integration/testing after my holiday. Thanks for implementing this so quickly!
Hello,
I have spend half the night to add this because i find this is a fundamental feature.
At this point i am testing the… Solar inverter malfunctions . So homeflux now is only buying energy, evade import at high tariff and saves battery while only guarding my energy consumption with peak guard..
Happy holiday and thanks for your valuable time!
HomeFlux EMS is currently undergoing certification. Once that process is completed, the refined EV charging logic will be included in a subsequent live release.
For EV planning, the intended approach is to let the vehicle or vehicle app provide the actual charging requirement to HomeFlux through the existing Flow card.
For example:
If a specific trip is planned, the vehicle app can send: 80% SoC required by 07:00, guaranteed = Yes.
If no specific trip is planned, it can send a default availability requirement such as: 30% SoC required by 06:30, guaranteed = Yes.
The guaranteed target is treated as a minimum requirement, not as a maximum charge level. HomeFlux may therefore continue charging beyond 30% whenever favourable tariffs, PV surplus or other configured charging opportunities are available.
When a new requirement is sent, it replaces the previous planning target for that EV. This allows the vehicle app to dynamically switch between a normal daily reserve and a higher SoC requirement for a planned journey.
In this setup, the vehicle or vehicle app determines how much energy is required and by when, while HomeFlux determines how that requirement can be met most efficiently within the configured energy strategy.
One additional refinement is currently in development. In the current test release, the EV will charge correctly, but HomeFlux does not yet have an explicit end-of-charge signal from every possible charger integration. The development version therefore supports an additional Flow card that can be triggered when the vehicle stops charging.
If that stop signal is not available, HomeFlux can also detect the end of the charging session indirectly: once the measured grid/load consumption falls back to approximately the learned average household consumption from before the EV charging session, the EV-related grid-import allowance is released again. This prevents HomeFlux from continuing to reserve grid-import capacity for an EV that is no longer charging.
Hi Davy, congratulations on this great step! HomeFlux is developing incredibly fast, and I really think it has the potential to become one of the most appreciated Homey apps. The combination of smart energy optimisation, flexibility and the way you keep adding practical features is very impressive. Great work — and well deserved!
Thank you so much! There was only one point holding the release back: the number of Flow cards — and I agree
All battery, EV and HVAC cards have now been replaced with new cards that only show the devices and functions you have actually configured. Existing cards will continue working invisibly for backwards compatibility, and the new version has been submitted.
One remaining question before I continue testing Hybrid EMS with my SMA Sunny Tripower Smart Energy + SHM2 setup.
For the Flow card “Set external EMS battery setpoint” / set_external_ems_setpoint, what exactly should be fed back to HomeFlux while SMA/SHM2 is handling self-consumption?
Should this be:
the actual measured battery power currently used by the inverter, or
the setpoint/requested power of the external EMS?
With SMA/SHM2 I currently have reliable measured battery power, but I have not found a reliable readback of the internally accepted/requested battery setpoint. I therefore do not want to use measured battery power as a proxy unless that is the intended contract.
For Hybrid EMS, you can feed the actual measured battery power back to HomeFlux. You do not need to retrieve the internal requested/accepted SMA/SHM2 setpoint.
Although the Flow card is currently called “Set external EMS battery setpoint”, the value is used by HomeFlux as feedback of the effective battery power while control is delegated to the external EMS.
So in your SMA/SHM2 setup, the reliable measured battery power is the correct value to use.
Please use the HomeFlux sign convention:
positive = battery discharge
negative = battery charge
If SMA reports the opposite sign, simply invert it before sending it to HomeFlux.
While HomeFlux itself has battery control, feedback through this card is ignored.
I’ll rename the visible Flow card text in a future version to something clearer, most likely “Report external EMS battery power”. The existing Flow card itself will remain compatible.
This Flow card is only used to improve HomeFlux’s internal energy and cost calculations while control is delegated to the external EMS.
It is not used as the primary control or safety feedback signal. HomeFlux continues to monitor the P1/grid measurement independently to verify the actual power exchange with the grid.
So if the external battery-power value is temporarily unavailable or slightly delayed, HomeFlux still has the P1 measurement as its reference for what is actually happening at the grid connection.
This version mainly contains two things to verify.
1. EV – Smart / Standard grid budget
For chargers without direct Ampere control, HomeFlux now uses the configured Smart and Standard current as the maximum EV grid budget.
Example for 3-phase:
Smart 6 A → maximum about 4.14 kW
Standard 16 A → maximum about 11.04 kW
Please check especially whether additional household consumption, such as an oven, cooking hob, or heat pump, no longer increases the detected EV load and therefore does not increase the EV grid budget.
Peak Guard always remains the hard upper limit.
2. External EMS battery card
The existing Flow card:
Set external EMS battery setpoint
is now called:
Report external EMS battery power
Please verify that:
existing Flows keep working without changes;
the card does not need to be added again;
reported battery power still reaches HomeFlux correctly;
external EMS / battery planning continues to work normally.
The card ID and behavior are intentionally unchanged; only the visible name was changed.
Thanks — both changes are directly relevant for my setup.
The new Smart/Standard grid-budget logic looks especially useful for my 3-phase Zappi setup. I’ll verify that extra household loads no longer inflate the detected EV load/grid budget, while Peak Guard still behaves as the hard upper limit.
The renamed external EMS battery card also makes the Hybrid EMS intent much clearer. Good to know the card ID and behaviour stay unchanged, so existing Flows should remain compatible.
Auto-update is enabled here, so 0.7.15 will probably install overnight. I’m still on holiday at the moment, but later this coming week I’ll be back home and can properly test both the EV behaviour with the car connected and the Hybrid battery feedback in the real installation.
. So homeflux now is only buying energy, evade import at high tariff and saves battery while only guarding my energy consumption with peak guard..
