German Red Cross Retirement Home Jungfernkopf

Secure power supply with Sunny Backup 5000

The German Red Cross in Kassel relies on solar power: the retirement home Jungfernkopf with 77 residents provides space for five common rooms that are grouped around four inner courtyards. The photovoltaic plant with a total power output of 57.6 kWp on the roof of the retirement home ensures a environmentally friendly solar power supply.

Thanks to the SMA Sunny Backup-System, the retirement home is optimally protected against power outage. In the event of a grid failure, the intelligent system automatically switches to Backup operation within only 20 ms: the main consumers will continue to be supplied from the battery or parts of the solar power plant.

Kassel, Germany

November 2008

Nominal power
57,6 kWp

Sunny Backup 5000
Sunny Mini Central 10000TL

Planning and realization
Solartechnik Stiens GmbH & Co. KG, Kaufungen

Plant size

  • 15 kW nominal power Sunny Backup
  • 57.6 kWp total PV power, thereof 33 kWp PV power at Backup
  • 1.200 Ah/48 V (58 kWh) battery

Information on the plant

  • Location: Kassel, Germany
  • Operator: German Red Cross, district chapter Kassel Wolfhagen e. V.
  • Planning and realization: Solartechnik Stiens GmbH & Co. KG, Kaufungen
  • Commissioning: November 2008

Power Consumers of Backup

  • Nurse call system
  • Telephone system
  • Heating
  • Kitchen components
  • Sockets in the common rooms


  • Sunny Backup 5000
  • Sunny Mini Central 10000TL


SMA Solar Technology AG
Sonnenallee 1
34266 Niestetal

Telefon: +49 561 95 22-4000
Telefax: +49 561 95 22-4040