tariffs have already been successfully introduced in several countries and we
expect to hear a lot more about them in the future. In this article, we will
explore how system owners can make the most of this tariff model. Owners of PV
systems with a battery storage system are set to benefit the most from
time-of-use electricity tariffs. With the right settings, the storage solution
can be adapted to suit both the customer’s daily routine and the electricity
tariff. This means that PV systems will turn a profit much sooner and system
owners can also save on energy costs as they can draw the electricity they need
from the grid at the cheapest times. And the best thing is, Fronius already has
a solution to make this setup a reality – the Symo Hybrid inverter.
What are time-of-use
Time-of-use electricity tariffs mean that customers pay a
different rate for their energy at different times of day. There are usually
two to five different phases – this Australian example is made up of three:
/ Peak phase: electricity is most expensive during this phase as
there is a high demand for energy
/ Shoulder phase: customers pay a moderate price for energy during
/ Off-peak phase: the electricity price is lowest during this
phase, which is often during the night
The electricity tariffs often also depend on the time of year. In
summer, the peak phase usually occurs during the day, as large numbers of
air-conditioning systems are in use due to the heat.
What are the advantages of
time-of-use electricity tariffs?
Time-of-use electricity tariffs are intended to give customers an
incentive to use energy at times when the general demand is low, and therefore
the electricity price is at its lowest at these times. As a system owner, this
enables you to lower your electricity bills and play a role in load management
and reducing the load on the grid infrastructure. Of course, it is not always
possible to shift your energy consumption to the times with the lowest
electricity price. However, an energy storage system allows users to store
energy either when the electricity price is low or when there is sufficient PV
The Fronius solution for
time-of-use electricity tariff
Fronius already has a solution for countries where energy
providers offer time-of-use electricity tariffs – the Symo Hybrid inverter.
With the Fronius Symo Hybrid, users can define time periods for charging and
discharging the energy storage system. System owners can therefore adapt their
storage solution to their individual needs and avoid unnecessarily high costs
for extra – and above all, expensive – energy from the grid.
More specifically, this means that the battery is charged and
discharged at certain times in order to reserve capacity for times of the day
when the more expensive electricity rates are in force. For example, if the
electricity tariff is particularly high in the evening, users can ensure that
the battery has enough capacity in the evening to cover this expensive phase
with self-produced electricity.
This is achieved by applying settings that limit discharging
during the phase in which electricity is at its cheapest.
Some countries also allow batteries to be
charged with electricity from the grid. This makes it possible to charge the
battery cheaply during periods when the electricity tariff is less expensive
and then subsequently use this energy during the more expensive tariff phases.
There are also countries, such as Australia, which offer
time-dependent feed-in tariffs. Here too, the Fronius solution can be
configured take these time-dependent feed-in tariffs into account and therefore
allow the biggest possible yields to be achieved.
Would you like to know more? The “Time-of-use settings with
Fronius Symo Hybrid” white paper contains more information about time-of-use
electricity tariffs and real-life examples.