SMA HM-20 - Entering Peak Load Shaving

10 Configuration of the SunnyHomeManager system
SMA Solar Technology AG
Operating manualHM-20-BE-en-1946
The time period control for battery charging competes with the regular control of a battery or hybrid inverter. As soon
as a time period for battery charging has been defined, the values energy self-sufficiency / self-consumption quota and
self-sufficiency quota / self-consumption quota are therefore hidden in the energy balance of the system. Background:
Due to set specifications of the battery charging power and time periods, it is likely that energy from the utility grid is
also used for charging the battery. This can distort the above-mentioned values significantly and permanently. Should
all time frames be removed at a later time, incorrect values might then be displayed.
You can specify time periods for several days as well as several consecutive time periods within a specific day.
Procedure:
1. In the Time period area click on .
2. Enter time interval (in 15 minute steps).
3. Select the period for which this time interval shall apply.
4. Enter the charging power in W.
5. To enter another time period, click on again and repeat the procedure.
6. You can undo unwanted entries with .
7. Confirm all your entries with [Save].
10.4.6 Entering Peak Load Shaving
This function was primarily developed for the Belgian Market and may not be useable yet in other countries.
In addition to optimizing the self-consumption portion by integrating electrical loads into the energy management
system and what is known as atypical grid use (switching on loads specifically at times when your solar system is
providing a lot of its own energy), you can save further electricity costs by reducing your power consumption from the
utility grid through intelligent setting of your battery storage system.
An increased energy demand at certain times of day (e.g. in the morning or in the evening) leads to so-called load
peaks, which can have you classified into a higher tariff category.
The battery-storage system allows you to capture, i.e. "shave" these load peaks with stored electric current. The
following settings are used for this:
Setting Explanation
Peak load shaving By activating the operating mode "Peak load shaving", you can specify the maximum power
supply from the utility grid as well as a limiting value for the portion of the total storage ca-
pacity of the battery system for the peak load shaving.
Purchased energy
limit
Range: 0kW to
100000kW
Default: 0kW
The purchased energy limit specifies the maximum power that may be drawn from the trans-
mission line. When this power is exceeded, the energy required is drawn from the battery.
• As soon as the battery is discharged, the corresponding load can no longer be
operated.
• In order to be able to operate a load despite the battery's insufficient state of charge,
the purchased energy limit can be increased temporarily; see 'adaptive increase'. In this
case, the load is operated with electric current additionally drawn from the utility grid,
which needs to be compensated for as well.
SOC limiting value
Range: 0% to 100%
Default: 50%
By entering a SOC (state of charge of the battery) limiting value, the total storage capacity
of the battery system can be divided:
• Below the limiting value: used for peak load shaving
• Above the limiting value: used for increased self-consumption
If the value 40% is entered, for example, 60% of the battery charge can be used at times
when the currently generated solar power is insufficient for the required electricity supply; a
base of 40% is reserved for shaving current peaks.