Solarwatt shows new photovoltaic home storage system

Solarwatt is showing a new energy storage system for single-family-home rooftop solar arrays. The single-phase Battery-Vision product can be configured with a capacity of 5.2 kWh and be expanded up to 18.2 kWh. It can be installed as a DC or AC variant.

That versatility makes the product equally suitable for new installations and retrofits. The storage unit, designed by BMW, contains lithium iron phosphate cells that can be stacked on top of one another in a modular manner. Battery-Vision features a unit with feet, for the floor, and a module that always forms the top. Both units each have 2.6 kWh capacity. Up to five additional 2.6 kWh battery modules can be added.

The nominal voltage of the system is 57.6 V, on the DC side. The battery voltage can be between 40 V and 480 V. Charging and discharging takes place with a maximum of 50 A. Temperatures of a maximum of 55 C are permitted during normal operation. The lowest temperature when charging should not be below 0 C. When discharging, however, the temperature can be as low as -10 C. In addition to the possible temperature range, the IP65 protection of the product housing also enables the system to be installed outside.

Battery-Vision can only be combined with the Solarwatt Inverter vision one 1.0 and vision three 1.0 products. The inverter is available in five power classes from 6 kW to 12 kW at the DC photovoltaic input. All come with two maximum power point (MPP) trackers, each with one input. The maximum system voltage is 600 V. The short-circuit current on the MPP tracker must not exceed 20 A.

“The battery absorbs a lot of energy very quickly and can then release it just as efficiently when needed (performance rate 1C),” says Solarwatt Chief Product Officer Peter Bachmann. “This is of utmost importance when charging an electric car or operating a heat pump with the help of the storage unit, for example. Our new generation of storage units reacts around three times faster than comparable products from our competitors.”

The inverters also enable a supply of single-phase emergency power from the battery. The inverter switches over independently in less than 20 milliseconds, ensuring an uninterrupted power supply. Solarwatt specifies the switchover time as less than 20 milliseconds. The maximum output of the emergency power supply is between 3 kW and 6 kW. The system can also charge mains power if it is available at a reasonable price through the use of dynamic electricity tariffs.

The Solarwatt product has passive cooling, which reduces the noise level during operation by 35 decibels. Solarwatt offers a guarantee of up to 10 years on the system.

From pv magazine Deutschland.