The present work relies on the topic of energy storage for Heat and Electricity applied to Heat Pump Water Heaters coupled with photovoltaic plants for Domestic Hot Water production. The main idea is to evaluate the possibility to exploit the water tank as heat storage for the produced photovoltaic energy and, where appropriate combined with electrical storage. For this reason, two heat pumps with different volume size have been chosen and smart control strategies have been applied while monitoring the water temperature in the tank. Calculations account on tapping profile inferred from monitored data of a representative end-user in a Mediterranean small island. Results show how the combination of smart control strategies and battery systems is the most suitable solution in order to fulfil the domestic hot water energy demand by renewable sources while maintaining comfort requirements. © 2019. The Authors. Published by International Solar Energy Society Selection and/or peer review under responsibility of Scientific Committee