SMA SI 3.0-11 Quick Reference Guide V.4.0 - Manual (Page 12)

3 Information and System Description SMA Solar Technology AG
12 FSS-IS-en-40 Installation Manual - Quick Reference Guide
3.3 System Description
The SMA Flexible Storage System supports increased self-consumption through the following measures:
• Intermediate storage of excess PV energy with Sunny Island
• Load control and PV system monitoring with Sunny Home Manager
The Sunny Island uses the connected battery for the intermediate storage of excess PV energy. The Sunny Island measures
the grid feed-in and the purchased electricity with the SMA Energy Meter or via the energy meter on the Sunny Home
Manager. The battery management uses this data to regulate the charging and discharging of the battery. The grid
feed-in and the purchased electricity are transmitted to the Sunny Island via Speedwire. To enable this, the Sunny Island
must be fitted with the Speedwire data module Sunny Island.
The Sunny Home Manager receives location-based weather forecasts via the Internet and uses these to create a
production forecast for the PV system. In addition, the Sunny Home Manager determines how much energy is typically
consumed in a household at different times of the day and uses this to create a load profile of the household. The
Sunny Home Manager uses the production forecast and the load profile to determine favorable times for increased
self-consumption and selectively switches, for example, the loads connected to the SMA radio-controlled sockets on and
off. If required by the grid operator, the Sunny Home Manager also monitors the active power feed-in of the PV system.
If the set maximum value for active power feed-in is exceeded, the Sunny Home Manager sends power reduction
commands to the SMA PV inverters. The PV system can consist of PV inverters with BLUETOOTH communication and PV
inverters with Speedwire communication.
Prevention of derating losses
The SMA Flexible Storage System prevents derating losses which may arise due to the limitation of active power feed-in.
This is achieved by regulating the operation times of time-independent loads and the time and duration of battery
charging in accordance with the PV production forecast and the consumption forecast.
Deactivation of the intermediate storage of PV energy during certain charging procedures
To increase the service life of the battery, the SMA Flexible Storage System regularly carries out full and equalization
charges (see the Technical Information "Battery Management" at www.SMA-Solar.com). During this charging process,
the intermediate storage of PV energy is deactivated and electricity may have to be purchased to perform the full and
equalization charges.
The Sunny Home Manager does not support wind power inverters or CHP plants
The Sunny Home Manager only supports PV inverters. If your system combines various AC power sources
(e.g., PV system and small wind turbine system), the Sunny Home Manager can only detect the PV inverters and limit
their power. In the Sunny Home Manager system, no wind power inverters or CHP plants are displayed in
Sunny Portal. Since the data from wind power inverters or CHP plants is not taken into account by the Sunny
Home Manager, the data calculated in Sunny Portal and the displayed diagrams may be inaccurate. However, you
have the option of displaying the wind power inverters via the Sunny Explorer software and configuring them if
necessary (see documentation of Sunny Explorer).
Example: The current daily forecast of the system predicts a limitation of active power feed-in around noon when the
energy requirement of the loads is very low and PV production is high. For this reason, derating losses can be expected.
According to this forecast, the system only begins to charge the battery in the late morning. The derating losses will be
reduced or avoided by charging the battery at this later time. The total excess PV energy generated in the morning will
be fed into the utility grid without derating losses (for details on power control, see Planning Guidelines
"SMA Smart Home").