Guide
Multi-brand HEMS for Home Assistant: how does it work?
The HEMS is the brain of a solar installation with batteries. A manufacturer's HEMS only handles its own brand; TED Energy Controller relies on Home Assistant to control them all together.
In short
A HEMS (Home Energy Management System) is the software that decides, moment by moment, whether to charge or discharge the batteries and at what power, so that you use your own solar production. TED Energy Controller is a multi-brand HEMS for Home Assistant: Home Assistant provides each device's measurements and controls, TED provides the shared control logic. It reads the grid meter every few seconds, computes a single setpoint and splits it between every inverter and battery, whatever their brand.
What a HEMS does
A solar installation with batteries constantly has to make trade-offs: store the surplus rather than export it to the grid, draw from the batteries when the house uses more than the panels produce, and never exceed any device's limits.
The HEMS makes these decisions in a loop. It measures the grid exchange at the meter, picks a mode (charge, discharge or standby) and a power level, then sends setpoints to the inverters. The most common goals:
- zero export: keep the grid around 0 W so you do not give your production away;
- less import: cover the household consumption with stored energy;
- off-peak charging: charge from the grid when electricity is cheapest;
- battery protection: respect minimum and maximum state of charge and each device's power limits.
The manufacturer HEMS: effective, but limited to its brand
Every battery or hybrid inverter maker ships its own HEMS in its app. It knows its own devices perfectly, but ignores other brands: their state of charge, their power, their limits.
As soon as an installation mixes two brands (a Zendure battery added to a Deye hybrid inverter, an Anker SOLIX next to a Marstek…), two brains read the same meter and each makes its own decisions. At best they share the work badly, at worst they fight each other: one battery drains while the other stays full, or both oscillate.
The most common limits are covered on Go beyond the limits of your manufacturer's HEMS.
Home Assistant provides the devices, TED provides the logic
Home Assistant already talks to almost every piece of solar equipment through each brand's integration: state of charge, power values, charge or discharge setpoint. But it has no control loop able to split a setpoint between several batteries.
TED Energy Controller adds that central logic. It does not talk to the devices itself: it uses the entities the integrations already expose. Any brand present in Home Assistant can therefore be controlled, with no extra hardware.
The meter is read through Home Assistant (or directly on the local network for a Shelly), and setpoints go back through Home Assistant to each inverter. A device you cannot, or do not want to, control stays included read-only: it is taken into account without ever receiving a command.
Several batteries controlled as one
For the control loop, all your batteries form a virtual battery: one total capacity, one overall state of charge, one setpoint. TED works out what the house must absorb or supply, uses only the devices needed (the emptiest first when charging), shares the power according to each one's maximum power and respects the limits set for every device.
A faulty device (self-calibration, setpoint ignored, lost communication) is set aside, the others take over its share, then it is retested automatically. The principle is explained on the Virtual battery page.
With or without the manufacturer HEMS
- Assisted mode: one brand's HEMS keeps control of its devices, which are monitored; TED puts the others to work as reinforcement, as a secondary HEMS.
- Autonomous mode: TED alone regulates the whole installation around a target (for example 0 W at the meter), single or different depending on the time of year.
- Scheduled charging: grid charging from a calendar, or automatically during off-peak hours (French HP/HC and Tempo tariffs).
What you need for a multi-brand HEMS
- Home Assistant on your local network.
- Your inverters and batteries in Home Assistant, through each brand's integration: state of charge, power values and, to control them, a charge or discharge setpoint.
- A grid meter visible in Home Assistant: a sensor from your electricity meter, or a Shelly (Pro 3EM, EM…) in your consumer unit.
- An always-on machine: Home Assistant OS (TED installs as an app), a Synology NAS, a mini-PC or a Raspberry Pi with Docker.
Zendure (SolarFlow, Hyper) is tested and validated; Huawei, SMA, Victron, Deye, Anker SOLIX and the other brands present in Home Assistant are compatible through their integration. Details on the Compatibility page.
What about other tools?
EMHASS, Predbat, evcc or Omnibattery address related needs: planning around prices, charging an electric car, directly controlling a list of supported batteries. The Home Assistant HEMS comparison explains what each one does and which to choose.
Frequently asked questions
What does HEMS stand for?
Home Energy Management System. It is the software that decides when to charge or discharge the batteries, and at what power, so that you use your own solar production.
Is Home Assistant a HEMS?
Not on its own. Home Assistant connects and displays your devices, and its Energy dashboard measures the flows, but it has no control loop that splits a setpoint between several batteries. You can write one yourself with automations, or add a HEMS such as TED Energy Controller, which uses Home Assistant to reach the devices.
Can I keep my manufacturer's HEMS?
Yes. In assisted mode, one brand's HEMS keeps controlling its devices and TED adds the others as reinforcement. In autonomous mode, TED regulates the whole installation as one.
How many batteries can a multi-brand HEMS handle?
TED has no software cap with an ACCESS or FULL POWER license. The FREE license, free with no time limit, controls 2 inverters; monitored devices are unlimited.
Does the control loop depend on the Internet?
No: it runs locally and measurements stay at home. The Internet is only used for the periodic license check; the Privacy page lists exactly what is sent.
Further reading
Make several battery and inverter brands work together
Each manufacturer app ignores other brands. Here, they all work together under one setpoint.
Read the solutionVirtual battery: control several batteries as one
One setpoint for all your batteries: they share the work instead of getting in each other's way.
Read the solutionGo beyond the limits of your manufacturer's HEMS
One brand, few settings, a limited number of devices: go beyond these limits, with or without the original HEMS.
Read the solutionReady to make all your batteries work together?
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