The paper investigates the potential of using lumped stationary battery energy storage systems (BESS) in the public low-voltage distribution grid in order to defer upgrades needed in case of large penetration of electric vehicle (EV), electrified heat pump (HP) in presence of photovoltaic (PV) panel on the view of techno economic optimal sizing taking the consideration of season-based diurnal dynamics. The BESS is primarily dimensioned for the peak shaving operation targeted for the counterbalance of overloading of transformer; BESS also participates in arbitrage (buy low, sell high) application. The paper assesses the effects of a PV-BESS combination and the control of such a system with the help of a newly devised season specific BESS control protocol that ensures the availability of energy for peak-shaving purpose (namely peak period in winter) and it participates in arbitrage. The objective of this paper is to develop and detail the method of optimum sizing energy storage for grid connected distribution systems using newly devised BESS control protocol and investigate its sensitivity to factors which are known to influence energy system performance and hence storage requirements. The results provide insight into the dimensioning and the required specification and configuration of BESS.