A hybrid energy system, based on renewable energy sources and with hydrogen storage, can become an alternative for stand-alone electricity and heat supply. The objective of this work is to evaluate the feasibility of a completely renewable supply of power and heat for an isolated household, and...

Development of the utilisation of renewable energy sources and energy efficiency represents the main policy for sustainable development. The overall target of the European Union Directive on the promotion of the use of energy from renewables (RES) is to achieve at least a 20% share of energy...

This paper presents the possibility of exploiting low-temperature heat from the generators' cooling system within a hydro power plant, using a HTHP (high temperature heat-pump) that enables heating at up to 85 °C.

This article examines different passive and active heating systems for swimming pools. The passive systems introduced in this article are:

The first Romanian passive office building has been constructed by the AMVIC Company in Bragadiru, 10 km south of Bucharest. The overheating rate and the cooling load are higher for a passive building than for a standard building. The internal heat sources and the maximum allowed indoor...

A stand-alone power system that consists of a photovoltaic array and wind generators for the exploitation of renewable energy sources (RES), and that is capable of storing excessive energy in the form of hydrogen via water electrolysis for subsequent use in a polymer electrolyte membrane (PEM)...

Hybrid renewable power generation systems considering storage of energy and/or hydrogen involve considerable complexity as heterogeneous equipment need to be interconnected and activated or deactivated at different time instances. This work employs generic and flexible decision making models to...

The variable electricity output of the RES (renewable energy sources) power plants, such as wind and hydropower, is an important challenge for the electricity system managers. This paper addresses the problem of an electricity system supported mainly on hydro, thermal, and wind power plants. A...

The high wind and solar potential along with the extremely high electricity production cost met in the majority of Greek Aegean islands comprising autonomous electrical networks, imply the urgency for new renewable energy sources (RES) investments. To by-pass the electrical grid stability...

Unlike the present energy system based on fossil fuels, an energy system based on renewable energy sources with hydrogen and electricity as energy carriers would be sustainable. However, the renewable energy sources in general have less emergy than the fossil fuels, and their carriers have lower...