Effects of the electricity consumption profile on the optimal renewable energy supply

The transition to weather-dependent renewable energy sources makes managing the temporal distribution of energy demand pivotal. This paper examines how the distinct characteristics of load profiles affect the levelized cost of electricity (LCOE) and the optimal technology mix of a hybrid renewable energy system (HRES) covering a pre-defined ratio of the electricity consumption. The proposed method involves the physical modeling of photovoltaic (PV) and wind turbine (WT) power production and the joint optimization of the operation of three energy storage technologies, namely lithium iron phosphate (LFP) and sodium-sulfur (NaS) batteries and hydrogen, and the installed capacities of all components with linear programming. All results are presented as a function of the renewable coverage ratio, enabling analysis across the entire pathway of a renewable energy transition. Nine measurement-based load profiles are considered, representing all combinations of three daily and three seasonal consumption trends. The LCOE of supplying the least favorable load profile is up to 88% higher than that of the most favorable one for small-scale systems consisting of four households supplied by only PV and LFP. This difference reduces to 42% if all five technologies are included in a town-sized community, which highlights the benefits of larger-scale energy communities with a diverse technology mix. The seasonal consumption habits are found to have a greater impact on the optimal cost and sizing than daily usage behaviors. Renewable energy production has largely different costs at different parts of the year, calling for a shift in the paradigm that energy efficiency is judged based on the amount of consumed or saved energy, since changes in the temporal distributions are becoming equally important.