Battery for PV Balcony System - Multiple Output Options
A storage unit for the balcony power plant stores the excess electricity generated by the panels at midday – more than the flat currently needs – and releases it again in the evening. These storage units are available individually, for retrofitting an existing balcony power plant or for expansion. The range includes: Growatt NOAH 2000 and NEXA 2000, Anker SOLIX Solarbank 3 E2700 Pro and the EcoFlow DELTA 2.
A comparison of the storage systems
| Storage | Capacity | Expandable up to | protection rating | Charge cycles | Warranty |
|---|---|---|---|---|---|
| Growatt NOAH 2000 | 2,048 kWh | 8,192 kWh | IP66 | 6,000 | 10 years |
| Growatt NEXA 2000 | 2,048,kWh | 8.19 kWh | IP66 | 6,000 | 10 years |
| Anker SOLIX Solarbank 3 E2700 Pro | 2,688,kWh | 16.13 kWh | IP65 | 6,000 | 10 years |
| EcoFlow DELTA 2 | 1,024,kWh | 2,048 kWh | – | 3,000 | 5 years |
| EcoFlow DELTA 2 Max | 2,048,kWh | – | – | 3,000 | 5 years |
All figures are taken from the manufacturer’s specifications on the product. All storage units use lithium iron phosphate (LFP) cells. According to the manufacturer, Growatt, NOAH 2000, NEXA 2000 and EcoFlow DELTA 2 Max can be controlled via the app using Wi-Fi and Bluetooth.
Two ways to integrate the storage unit
The Growatt NOAH 2000 is positioned between the modules and the micro inverter. It supplies direct current, so the inverter remains necessary. It is available as a ready-to-use combination with the Growatt NEO 800M-X and a 5 m Schuko cable as part of the storage-inverter sets. It charges at up to 1,800 W.
The Growatt NEXA 2000 has its own 230 V AC output. According to the data sheet, it charges at up to 2,000 W and delivers up to 800 W. The NEXA expansion module provides additional capacity, with 2.048 kWh each. The Anker SOLIX Solarbank 3 E2700 Pro can be expanded to 16.13 kWh according to the data sheet.
The EcoFlow DELTA 2 and DELTA 2 Max are portable energy storage units that can also be used independently of the balcony power plant. The DELTA 2 can be expanded by 1.024 kWh with the DELTA-2 on storage unit.
Check before buying
Three factors determine whether a storage unit is compatible with your existing balcony power plant: the power output of the modules, as each storage input has an upper limit; whether the existing micro inverter continues to operate or the storage unit performs grid feed-in; and the installation location. The Growatt storage units and the Anker are rated to IP65 or IP66; the catalogue does not specify a protection rating for the ‘EcoFlow DELTA’; they must therefore not be left outdoors unprotected. The data sheet specifies which modules and inverters the manufacturer approves.
Complete systems comprising modules, inverters and storage units can be found under Balcony power plants with storage. Storage units for a rooftop system with a hybrid inverter can be found under Storage units for inverters.
For photovoltaic systems and their essential components, no value added tax is charged where the conditions of Section 12 (3) of the German VAT Act (UStG) are met. You state during the ordering process whether they apply to you.
Frequently asked questions about balcony power plant storage systems
Can I connect a storage unit to my existing balcony power plant?
Yes, these devices are designed for this purpose. The data sheet specifies which modules and inverters a storage unit is compatible with; with the Growatt NOAH 2000, the micro inverter remains part of the system.
How much storage capacity does a balcony power plant need?
That depends on your evening consumption. The storage units here have a capacity of 1 to 2.7 kWh and some can be expanded; for the Growatt, this goes up to around 8 kWh, and for the Anker, up to 16.13 kWh.
Can I expand the memory later?
For the Growatt NEXA 2000, this can be done using the NEXA expansion module; for the EcoFlow DELTA 2, using the DELTA-2 additional storage. According to the data sheet, the NOAH 2000 and Anker Solarbank 3 Pro are also expandable.