  Due to the 2012 change in the renewable energy act the feed-in tariffs and as
result the number of newly installed photovoltaic systems decreased
dramatically in Germany. Therefore, there was the need, particularly, in the
residential sector to develop new business ideas for photovoltaic systems. In
context of this development, combined photovoltaic and heat-power systems were
analyzed, which provide not only electricity but also heat throughout one
entire year. Flexibilities are provided in form of thermal and electrical
storage systems leading to many possible setting options requiring an
elaborated control management. In this paper, a new optimized control algorithm
is proposed that in contrast to standard strategies can operate optimal even
under incorrect weather and load forecasts. A predictive controller based on a
mixed integer optimization problem and an additional so called secondary,
rule-based controller is combined. The controller is based on several input
data. Depending on the choice of these data the PV-CHP hybrid system can be
used for different control strategies, like maximum self-consumption, minimum
CO2 emission or minimum operational costs. The main focus in this paper is to
study if the flexibility potentials of the combined thermal and electrical
storage systems can ensure a market oriented or a grid-friendly behavior. This
is studied in five control options. As a result we found that the control
algorithm is stable and able to adapt to the different conditions. In
conclusion, it was discovered that the storage systems play a crucial role in
terms of forecast differences and parameter changes. Storage systems are as
expected the key-element for the flexibility of PV-CHP hybrid systems.
