© 2023 by XOLTA
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5.2.1.2 Grid tariff optimization
Grid tariff optimization is an improved mathematical algorithm based on the solar max self-consump-
tion mode and takes additional information such as weather forecast, historical load and electricity
price into account. The goal is to minimize the electricity cost for the user. The XOLTA system looks into
the high and the low price for each day and determines the day’s low price and high price regions.
The target is to allow charging from the grid in the low-price region and avoid import from the grid in
the high-price region, in addition to the utilization of solar production. By operating this mode, users
can expect to see a further decrease in energy bills compared to the maximizing solar self-consumption
mode, based on the differences between the high and low prices of the day.
The XOLTA system also takes the weather forecast and historical load profile of the user into account,
so that the system can estimate whether it is necessary to charge from the grid and how much energy
to store in the low-price region.
Figure 5.4. presents grid tariff optimization example. High-price and low-price regions are indicated in the
top figure, whereas the planned charge according to weather and historical consumption is shown in the
bottom figure.
Figure 5.4:
Grid tariff
optimization example
6
5
4
3
2
1
0
3.5
3
2.5
2
1.5
1
0.5
0
00:00
04:00
08:00
12:00
16:00
20:00
100
80
60
40
20
0
2.5
2
1.5
1
0.5
0
00:00
04:00
08:00
12:00
16:00
20:00
00:00
dkk/kwh
Price
Reserved SOC
Consumption
kwh
kwh
Possible economic saving 12%
DETAILS
POWER
High price consumption
