Developments in sustainable energy and environmental protection

This special issue on sustainable energy and environmental protection concerns with simulation and modelling aspects in this research filed. This editorial introduction “EI” highlights the different articles presented and discussed in this issue. In this issue, simulation and modelling were implemented to study environmental aspect such as; the three-pass perforated tube, heat pipe-based radiator, energy storage and recovery, efficiency of PEM fuel cell. In this special issue, simulation and modelling to optimise the building heating efficiency was presented. Vehicle engine with alternative fuel systems is also presented, mainly the gasoline direct injection and the stirling engine. Water quality and the rehabilitation of Lake Izvorul Muntelui in Romania is presented. Finally, this issue is concluded with an article regarding an important environmental issue such as the fire risk simulation system for multi-purpose building based fire statistics.The contents of this issue will be discussed in details in the following sections.