Marstek Venus E 4.0 pre-sale: 5 kWh, 3 kW battery
Pre-orders are open for the Marstek Venus E 4.0, the new generation of Marstek's plugin home battery. It stores 5 kWh of solar power, delivers up to 3 kW and connects to a standard socket. Three units combine for 15 kWh. Pair the Marstek Venus E 4.0 with our Performance 2000 kit or with the solar kit you already have.
What is the Marstek Venus E 4.0?
The Marstek Venus E 4.0 is a home battery with 5 kWh of storage and 3 kW of charge and discharge power. It connects to your home's circuit through a socket, not to your solar panels, so it works with new and existing solar kits.
How the Venus E 4.0 works
A Marstek Smart Meter in your electrical panel measures what your home takes from and sends to the grid. When your panels produce more than you use, the battery stores the surplus. When you need more, it discharges, up to 3 kW. The Marstek app controls it, and AI mode plans charging around your electricity tariff.
What is new compared with the Venus E 3.0
| Venus E 3.0 | Venus E 4.0 | |
|---|---|---|
| Storage | 5.12 kWh | 5 kWh |
| Charge and discharge power | 2.5 kW | 3 kW |
| Maximum system with Smart Box | Three units, 15.36 kWh | Three units, 15 kWh and 9 kW |
| Weight and footprint | — | 21% lighter, 7% smaller footprint |
Source for weight and footprint: Marstek's launch announcement, June 2026.
Key specifications
| Specification | Marstek Venus E 4.0 |
|---|---|
| Capacity | 5 kWh per unit |
| Battery cells | Lithium iron phosphate (LiFePO4), 314 Ah |
| Charge and discharge power | 3 kW |
| Backup socket | 3 kW, for devices plugged into the battery |
| Expansion | Up to three units with the Marstek Smart Box: 15 kWh, 9 kW |
| Cycle life | 10,000+ cycles |
| Warranty | 10 years |
| Expected lifespan | 15 years |
| Connection | Schuko cable to a standard socket |
Why the Marstek Venus E 4.0 matters for you
The Marstek Venus E 4.0 stores a full day's surplus from a larger solar kit and gives it back in the evening, with enough power for several appliances at once.
It stores the surplus of a 2,000 W kit
The Performance 2000 kit has four panels with 1,940 Wp in total. On a sunny day, a 2 kWh battery is full by late morning; the 5 kWh Venus E 4.0 keeps storing into the afternoon.
You save about €250 a year
With this battery you save about €250 a year, on top of what the panels save directly. The figure assumes:
- The battery fills with surplus on 200 days a year.
- About 4.25 kWh of each 5 kWh charge reaches your appliances after conversion losses.
- Each kWh costs €0.29, the EU average household price in the second half of 2025 (Eurostat).
4.25 kWh × 200 days = about 850 kWh a year. Your result depends on where you live, your consumption and your tariff.
It covers evening peaks
With 3 kW of output, the Venus E 4.0 runs a 2 kW oven and a fridge at the same time on stored solar power.
It keeps essentials running in a power outage
The 3 kW backup socket powers the devices plugged into it, such as a fridge, a router or a laptop. It does not power your home's wiring.
It is recognized by the industry
The tech site inside digital gave the Venus E 4.0 an Editor's Choice award at Intersolar Europe 2026 for its price per kWh of storage.
It is easy to set up
You connect the Venus E 4.0 to a socket and pair it with the Marstek app. The Smart Meter goes in your electrical panel and is installed by a qualified electrician.
Which Robinsun kit is right for you?
The Marstek Venus E 4.0 suits a 2,000 W kit or an existing solar system.
| Option | Panels | Panel power | Maximum output | Mount | Storage |
|---|---|---|---|---|---|
| Performance 2000 | Four Aiko Neostar 3P 485 Wp | 1,940 Wp | 2,000 W | Balcony, wall, flat roof, tile roof or metal roof | Add a Venus E 4.0 with Smart Meter |
| Venus E 4.0 on its own | Your existing kit | — | 3 kW from the battery | — | 5, 10 or 15 kWh, with or without Smart Meter |
For an 800 W kit, the Venus E Mini stores 2 kWh. See all our solar kits with storage or our guide on how to choose your home solar battery.
Frequently asked questions
When will my Venus E 4.0 ship?
The Marstek Venus E 4.0 is on pre-sale: you order it now and we ship it as soon as stock reaches our warehouse. Our team gives you the expected shipping date before you order, and we keep you updated by email until your battery ships.
Do I need the Smart Meter with the Venus E 4.0?
Yes, if you want the Venus E 4.0 to store your solar surplus automatically. The meter tells the battery when your home is sending power to the grid. Without it, you use manual schedules or charge from the grid. A qualified electrician installs the meter in your electrical panel.
Will the Venus E 4.0 work with my existing solar system?
In most cases, yes. The Marstek Venus E 4.0 connects to your home through a socket, on the AC side, not to your panels or inverter. That is why it works with most plugin solar kits and many rooftop systems. To store surplus automatically, it needs the Marstek Smart Meter.
Will the Venus E 4.0 power my home during a power outage?
The Venus E 4.0 has a 3 kW backup socket that keeps the devices plugged into it running during a power outage, such as a fridge, a router or a laptop. It does not power the lights and sockets wired into your home. Runtime depends on the charge level and what you plug in.
How do I expand the Venus E 4.0 later?
You combine up to three Marstek Venus E 4.0 units with the Marstek Smart Box. Together they store 15 kWh and deliver up to 9 kW. Start with one unit today and add more when your consumption grows. Our team checks with you what your home needs.
Pre-order your Venus E 4.0 today
The Marstek Venus E 4.0 stores 5 kWh of your own solar power, delivers 3 kW and grows to 15 kWh. Pair it with the Performance 2000 kit and a mount for your balcony, wall or roof.
Get the Performance 2000 with mount and battery
Already have a solar kit? Pre-order the Venus E 4.0 on its own or contact us and we help you choose.
