Next to your existing panels
The built-in AC inverter works with single- and three-phase inverters of any brand.
Sessy home battery
Sessy: the Dutch home battery next to your existing solar panels
Sessy has its own built-in inverter, so it works alongside almost any existing solar inverter, single- or three-phase. Choose 5 or 10 kWh and easily add a second or third Sessy later.
- 5 / 10 kWhtwo versions
- 5.2 / 10.4 kWhusable capacity
- 2.2 / 1.7 kWcharging / discharging per Sessy
- 10 yearswarranty on the battery
Sessy
Versions and combinations
Both versions use the same inverter and software. You get more power by combining several Sessys, optionally spread over the phases.
Sessy 2.0 per version
| Version | Total (kWh) | Usable (kWh) | Charging (kW) | Discharging (kW) | Weight (kg) |
|---|---|---|---|---|---|
| 5 kWh | 5.5 | 5.2 | 2.2 | 1.7 | 46 |
| 10 kWh | 11 | 10.4 | 2.2 | 1.7 | 96 |
Part of the capacity is not used to extend battery life. Dimensions: 41 × 20 × 67 cm (5 kWh) and 41 × 27 × 78 cm (10 kWh).
Multiple Sessys 10 kWh
| Number | Usable (kWh) | Charging (kW) | Discharging (kW) | Active phases |
|---|---|---|---|---|
| 1 | 10.4 | 2.2 | 1.7 | 1 |
| 2 | 20.8 | 4.4 | 3.4 | 1 or 2 |
| 3 | 31.2 | 6.6 | 5.1 | 1, 2 or 3 |
According to the Sessy datasheet. The 5 kWh version has the same power per Sessy.
What Sessy can do for you
Use your own solar power
With 'Zero on the meter' you use as much of your own generation as possible.
Dynamic contract
In dynamic mode Sessy charges at low and discharges at high prices, if your contract allows it.
Open, no mandatory subscription
App, online portal, local API and cloud API, also for Home Assistant or Homey.
Expansion, solar panels and energy management
| Expansion | Multiple Sessys can be combined; power and capacity add up per Sessy. |
|---|---|
| Solar panels | Suitable next to existing single- and three-phase PV inverters of any brand. |
| Sessy guideline | Sessy advises one 5 kWh per 3,000–4,000 kWh consumption and the 10 kWh from 5,000 kWh. We calculate your own situation. |
Backup power
The standard version does not provide backup power. The datasheet mentions a 48 V port for, among other things, a compact backup solution; we only offer it once it is confirmed for your situation.
- During a power cut the standard Sessy switches off, like the grid.
Placement and warranty
| Placement | Indoors (IP20), wall mounted or standing, 0–35 °C |
|---|---|
| Noise | 30–40 dBA nominal |
| Efficiency | Round-trip 85% according to Sessy |
| Warranty | 10 years on the battery (6,000+ cycles), 5 years on the inverter |
Does Sessy suit you?
A good fit if
- You already have solar panels and want to keep your inverter.
- You want to start small and expand later.
- You want open integrations without a mandatory subscription.
Worth considering
- Need backup power or more power per appliance? ATMOCE, Midea or Pylontech often fit better.
- Sessy is installed indoors; for outdoor placement we look at another brand.
At a glance: Sessy 5 kWh and 10 kWh
- Version & capacity
- 5 and 10 kWh versions; usable 5.2 / 10.4 kWh
- Power
- 2.2 kW charging / 1.7 kW discharging per Sessy
- Connection
- Single-phase connection; works with single- and three-phase inverters
- Expansion
- Multiple Sessys can be combined, also spread over phases
- Backup power
- Not with the standard version
- Placement & warranty
- Indoors (IP20); 10 years battery / 5 years inverter
Further reading: buying questions for all five brands · choosing the right capacity · savings calculator
Sources: sessy.nl/specificaties, Sessy 2.0 datasheets 5 kWh and 10 kWh (sessy.nl, September 2025) and the Sessy FAQ on power. Subject to change. Price and availability after advice.
Is Sessy the right choice for you?
We compare your consumption, connection and wishes with the five brands we work with and give you a substantiated proposal, without obligation.