Bluetti turns power stations into 800 W balcony storage

A large power station often simply sits around after a camping trip, in a motorhome or in the garden. In testing, the Bluetti Balco Transfer Hub turned it into grid-connected storage: Together with a Bluetti Elite 300 and a Shelly Pro 3EM, the system fed up to 800 W into the home grid and adjusted its output to current consumption.

When the household load rises, the hub increases the feed-in. When it falls, the hub reduces it again. The Shelly Pro 3EM measures electricity consumption for this purpose, while the Bluetti app integrates the smart meter into the control system. In everyday use, the combination therefore behaves largely like a conventional storage system for a balcony solar setup.

The crucial point lies inside: The Transfer Hub has neither its own battery nor a PV input or MPPT. The solar modules are connected directly to the power station; the Elite 300 has an MPPT input designed for up to 1200 W of solar charging power. Energy flows from the solar module through the battery and the power station’s AC output, via the hub, into the home grid. Because a power station’s 230-V output is not designed for direct grid feed-in, the hub provides the necessary grid-connected interface and stops feeding in when the grid is unavailable.

The combination can also feed surplus electricity into the grid: If the battery is filled to the configured charging limit and the solar modules continue to supply energy, up to 800 W of it can flow into the home grid. The hub itself remains a comparatively compact add-on device weighing around 4 kg and featuring IP54 protection. It draws a maximum of 850 W from the power station via AC and can charge at 2300 W in bypass mode.

So what does this change in practice? Anyone who already owns a compatible power station with several kilowatt-hours of capacity can also use it as stationary storage with little additional hardware, rather than buying a second battery. For a new balcony solar storage system, however, the balance looks different according to the heise test: Dedicated devices have their own PV inputs, require fewer conversion stages and are better suited to continuous stationary operation. The dynamic regulation worked reliably in testing, but the assessment applies to the tested combination and the current firmware version.