Sessy is a Dutch home battery made by Charged B.V. The original unit stores 5 kWh and units can be combined, and a 15 kWh Sessy Plus has been announced. It is managed through the Sessy app and web portal, and can also be steered through an open API.
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Sessy works as an energy device rather than a voice-controlled gadget. It stores surplus solar power, can follow dynamic energy prices, and can read a P1 or CT meter. Sessy's own app and portal handle everyday use, while a local REST API, an official Homey app and a community Home Assistant integration cover automation.
That suits Dutch households with solar panels who want a battery that Home Assistant or Homey can steer. It is weaker for anyone expecting Matter, Alexa or Google Home, and we found no Zonneplan integration, so dynamic trading is tied to the suppliers Sessy lists.
Source: Sessy app and portal explainer
The renewed app and web portal show energy insights per day, week, month and year, a power flow diagram, the current energy price and self-sufficiency. Operating mode and energy contract are chosen in account settings. We found the portal address but could not verify store links for the app.
Official supported by the brand Community built by someone else Not found searched, nothing found Unconfirmed sources conflict or could not be opened
| Platform | Status | What it means | Sources |
|---|---|---|---|
| Connection | |||
| Local network | Yes | The Home Assistant integration connects to the Sessy dongle by a hostname such as sessy-xxxx.local, and Sessy publishes an OpenAPI 3.0.3 description of a REST API for it. We could not confirm from Sessy's pages whether the dongle uses Wi-Fi or Ethernet. | ha-sessy Sessy API description |
| Proprietary radio | Yes | For Sessy Plus, a news report says the communication hub connects by Ethernet cable and broadcasts its own radio signal to the battery, with no SIM card needed. | Solar Magazine: Sessy Plus |
| P1 and CT meters | Yes | The Home Assistant integration and the Homey app both support a Sessy P1 meter. The Home Assistant integration also lists a CT meter, and the Homey app lists a Sessy CT. | ha-sessy Sessy on Homey |
| Modbus | Unconfirmed | The Homey app lists a Sessy Modbus device type. We found no Sessy page that documents Modbus, so the details are unconfirmed. | Sessy on Homey |
| Bluetooth, Zigbee, Z-Wave, Thread | Not found | No mention found on the Sessy pages we opened. | Searched, no source |
| Matter | Not found | No Sessy Matter announcement or support found when we searched. | Searched, no source |
| Voice assistants and ecosystems | |||
| Google Home | Not found | No Sessy Google Home support found when we searched. | Searched, no source |
| Amazon Alexa | Not found | No Sessy Alexa support found when we searched. | Searched, no source |
| Apple Home | Not found | No Sessy Apple Home or HomeKit support found when we searched. | Searched, no source |
| Dynamic energy contracts | Yes | With a dynamic contract Sessy fetches the current price every 15 minutes. Dynamic mode charges when energy is cheap and supplies power when it is expensive, and Eco mode also charges in the cheapest hours. | Sessy app and portal explainer |
| Frank Energie and Eneco | Unconfirmed | A comparison page by Zonneplan says trading on energy markets with Sessy needs SessyConnect and a dynamic contract from Frank Energie or Eneco. That page comes from a competing battery seller, and we did not find the same list on Sessy's own pages. | Zonneplan: Zonneplan vs Sessy |
| Zonneplan | Not found | We found no integration between Sessy and Zonneplan. Zonneplan's own page presents the two as alternative batteries and ties its market trading to a Zonneplan energy contract. | Zonneplan: Zonneplan vs Sessy |
| GridEase | Official | Sessy describes GridEase as a mode where a third party you choose operates the battery for grid services such as balancing, imbalance markets, GoPacs and emergency power. | Sessy app and portal explainer |
| Open platforms and developer access | |||
| Home Assistant | Community | A community integration by an individual developer installs through HACS and talks to the battery locally. It provides battery and meter sensors, power strategy and setpoint controls, EPEX prices, firmware updates and Energy Dashboard meters. It needs the local username and password from the device sticker. We found no built-in Home Assistant integration. Sessy itself says Home Assistant or Homey can control the battery in open mode. | ha-sessy Sessy app and portal explainer Home Assistant integrations |
| Homey | Official | Homey lists an official Sessy app published by CHARGED B.V. It works on Homey Cloud, Homey Pro, Homey Pro mini and Self-Hosted Server with Homey 12.13.0 or newer, and Homey Bridge is not listed. It supports Sessy, CT, Modbus, P1 and solar system devices and monitors and controls the battery. | Sessy on Homey Sessy on Homey (French listing) |
| evcc | Community | There is no official evcc support. Users on the Sessy forum report connecting evcc through the local API, with only Normal, Hold and Charge modes available. | Sessy forum: evcc |
| Domoticz | Unconfirmed | Sessy's forum lists Domoticz among external integrations. We did not find or open a Domoticz plugin page, so the details are unconfirmed. | Sessy forum: evcc |
| My Home Battery app | Community | An independent iPhone app by Patrick van Zweden monitors and controls a Sessy battery over the local network. Its listing says Sessy is the only battery supported so far. | My Home Battery (App Store) |
| openHAB | Not found | No binding found when we searched. | Searched, no source |
| Node-RED | Not found | No dedicated node found when we searched. | Searched, no source |
| Samsung SmartThings | Not found | No integration found when we searched. | Searched, no source |
| Hubitat | Not found | No driver found when we searched. | Searched, no source |
| Control4 | Not found | No integration found when we searched. | Searched, no source |
| IFTTT | Not found | No Sessy service found when we searched. | Searched, no source |
| Philips Hue | Not found | No integration found. | Searched, no source |
| Sessy local API | Official | Sessy publishes an OpenAPI 3.0.3 description (v1.1.0) of a REST API with JSON bodies. It covers power status, the active strategy, a power setpoint (only in the API strategy), energy totals and a dynamic schedule with EPEX day-ahead prices. The document does not cover authentication or the base address. A forum user reports that the local API needs no login, which is unconfirmed by Sessy. | Sessy API description Sessy forum: evcc |
Checked 11 November 2026 against the brand's own pages, app store listings and each project's own page. “Not found” means we searched and found nothing, not that it is impossible. Compatibility changes often. Spot an error? Tell us and we will fix it.
Not that we could find. No Sessy Matter announcement or support found when we searched.
Not that we could find. No Sessy Alexa support found when we searched.
Not that we could find. No Sessy Google Home support found when we searched.
Not that we could find. No Sessy Apple Home or HomeKit support found when we searched.
Yes, through a community-built integration. A community integration by an individual developer installs through HACS and talks to the battery locally. It provides battery and meter sensors, power strategy and setpoint controls, EPEX prices, firmware updates and Energy Dashboard meters. It needs the local username and password from the device sticker. We found no built-in Home Assistant integration. Sessy itself says Home Assistant or Homey can control the battery in open mode.
Not that we could find. No integration found when we searched.
Yes, officially. Homey lists an official Sessy app published by CHARGED B.V. It works on Homey Cloud, Homey Pro, Homey Pro mini and Self-Hosted Server with Homey 12.13.0 or newer, and Homey Bridge is not listed. It supports Sessy, CT, Modbus, P1 and solar system devices and monitors and controls the battery.
Not that we could find. No driver found when we searched.
Answers come from the sourced table above. See how Sessy compares with all brands on the smart home brand statistics page.
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