Hoymiles MS-A2 Review: The simplest balcony power station storage unit

The triumph of balcony power plants is unstoppable in Germany too. More and more people are generating their own energy at home. However, to ensure that too much electricity produced is not simply lost and fed into the power grid, there is the option of collecting surplus energy with a so-called balcony power plant storage unit. The recently introduced Hoymiles MS-A2 is a particularly innovative solution, as our test reveals.

Technical data

Hoymiles MS-A2 test: design and workmanship

The Hoymiles MS-A2 micro storage unit is designed to make it much easier to connect a storage solution for balcony power stations. The manufacturer advertises that the solution can be connected to your own balcony power station in just 7 seconds and is ready for use.

The new retrofit solution is compatible with all standard balcony power stations and is weatherproof to IP65, meaning it can also be used outdoors. In addition to the Hoymiles MS-A2, the scope of delivery includes a plug-and-play cable, a wall bracket and operating instructions.

The storage solution itself presents itself as a rather plain gray box with black design elements, which has various LED displays on the front that provide information about the charging status, the WLAN connection and more.

Two buttons (a power button and a settings button) ensure simple and intuitive operation, while integration takes place via Wi-Fi and Bluetooth, allowing the storage solution to be easily set up and monitored via a smartphone and accompanying app.

There is a Schuko plug and a power connection on the side, which testify to the ease of installation. At the rear, the MS-A2 has a generous heat sink and a protected air outlet.

Hoymiles MS-A2: Structure and battery

The manufacturer has undoubtedly not promised too much when it comes to the assembly of the Hoymiles MS-A2, as it is extremely simple. At least once you have balanced the 32 kg colossus out of the box and put it in its place.

To get started, all you have to do is unplug the existing micro inverter and connect it to the MS-A2. This is connected between the inverter and the mains and supplied with power as normal via the socket.

This is not only particularly simple and convenient, but also avoids potential complications, as the inverter of the energy storage system does not have to be set to the power output and MPPT of the micro inverter of the balcony power station. Connect, supply with power, done.

Under the hood of the MS-A2 is a 2.24 kWh battery that relies on modern and safe LiFePO4 technology. This is particularly durable and should withstand more than 6,000 charging cycles without any problems. It can easily withstand temperatures from 0°C to 55°C when charging and scores points with discharge temperatures from -20°C to 55°C.

A maximum charging capacity of 1,800 watts of solar energy is possible, provided your inverter allows it. A maximum of 800 watts can be fed into the household grid.

Hoymiles app and practical test

The AC connection of the Hoymiles MS-A2 naturally makes it very easy to set up. Simply connect the existing Schuko plug from the inverter to the energy storage system and you’re ready to go.

The app is of course the linchpin for operation. It provides information about the efficiency of the energy generation on the start page and clearly shows how much energy is being generated, supplied for domestic use and stored in the MS-A2.

Here you can also clearly see how much energy comes from the inverter, how much is contributed by the energy storage system and how much energy is released into the power grid. The values can of course be adjusted individually.

Statistics are also provided for the day, month, year and total energy generated. Further information can be called up in the menu of the storage unit itself. For example, about the operating temperature, energy curve or charging status. In the settings, the “Operation Mode” section can be used to set the “Portable Power Station Mode” and adjust the charge level.

You therefore specify the charging status at which the MS-A2 should either use the stored energy itself or be used as a power station for household devices. In the “Load Power Settings” area, the power can also be freely set up to a maximum of 800 watts. This means you can set whether and if so how much energy should be fed into the household grid.

The “Power Curves” can also be used to set how much energy should be fed into the household grid at what time of day. The off-grid mode also allows use in the event of a power failure. In this case, the earthed socket to which the inverter is connected becomes an output to which other electrical appliances can be connected and supplied with power if required. Very practical.

Hoymiles MS-A2 Review: Conclusion

The Hoymiles MS-A2 is an exciting energy storage solution for balcony power plants that scores points above all for its simplicity. Unpack it, connect it to the inverter and get started.

Thanks to the practical and clear app, you can always keep an eye on energy generation and demand and can set how much energy is to be used or fed in and when in just a few simple steps.

The weatherproof and robust design and high-quality workmanship are also impressive. With up to 2.24 kWh, the MS-A2 can also store a lot of energy and easily supply electrical devices with energy as a power bank in the event of a power outage or when traveling.

The Hoymiles MS-A2 is therefore the perfect addition for anyone who operates a balcony power station and does not yet have a storage unit. Not least because of its simple and innovative setup, but also because of its truly impressive performance values.