In Poland an increase in the of number solar thermal collectors is observed in household applications. For economic and ecological profitability the creation of a solar thermal installation design in a proper manner is essential.

In order to determine solar installations size, software calculating future solar heat gains is used. SHW software is an examples of such software. The aim of this work was to compare the simulation results with the real results of the solar installation operation. The comparison was performed by an example of a single-family house with flat plate collector installations located in south-east Poland. This installation supports domestic hot water preparation in a house occupied by four people (in two-year period of analyses). The additional heat source in this building is a gas boiler. Solar fraction parameter values were chosen for this comparison. Solar fraction is calculated as a ratio of solar heat gains used in the domestic hot water preparation process to the heat desired for domestic hot water preparation. The real results of Solar Fraction turned out to be higher than the simulation results from May to August (there were many days with Solar Fraction = 1). A difference of 20–50 percentage points was observed (Solar Fraction). Apart from this period no special differences were observed.

Additionally analyses of differences between solar heat gains calculated by Get Solar simulation software with real values (for analyzed building) was performed. This simulation analysis was done before process of building installations.

The current task explores automatic generation control knowledge under old-style circumstances for a triple-arena scheme. Sources in area-1 are thermal-solar thermal (ST); thermalgeothermal power plant (GPP) in area-2 and thermal-hydro in area-3. An original endeavour has been set out to execute a new performance index named hybrid peak area integral squared error (HPA-ISE) and two-stage controller with amalgamation of proportional-integral and fractional order proportional-derivative, hence named as PI(FOPD). The performance of PI(FOPD) has been compared with varied controllers like proportional-integral (PI), proportional-integralderivative (PID). Various investigation express excellency of PI(FOPD) controller over other controller from outlook regarding lessened level of peak anomalies and time duration for settling. Thus, PI(FOPD) controller’s excellent performance is stated when comparison is undergone for a three-area basic thermal system. The above said controller’s gains and related parameters are developed by the aid of Artificial Rabbit Optimization (ARO). Also, studies with HPA-ISE enhances system dynamics over ISE. Moreover, a study on various area capacity ratios (ACR) suggests that high ACR shows better dynamics. The basic thermal system is united with renewable sources ST in area-1 also GPP in area-2. Also, hydro unit is installed in area-3. The performance of this new combination of system is compared with the basic thermal system using PI(FOPD) controller. It is detected that dynamic presentation of new system is improved. Action in existence of redox flow battery is also examined which provides with noteworthy outcome. PI(FOPD) parameters values at nominal condition are appropriate for higher value of disturbance without need for optimization.