Micro combined heat and power (CHP) plants operating through an organic Rankine cycle (ORC) using renewable energy are analyzed. The reference system is designed to produce 50kWe. The heat sources of the system are geothermal energy at low temperature (80–100°C) and solar energy. Two...

A micro combined heat and power (CHP) plant operating through an Organic Rankine Cycle (ORC) using renewable energy is analysed. The reference system is designed to produce 50 kWe. The heat sources of the system are geothermal energy at low temperature (80–100 °C) and solar energy. The...

Glass heat pipe solar collectors are becoming very popular for heating/sanitary water production. The use of a double glass system, with vacuum in between (Dewar scheme), allows to minimize heat dispersion to the environment, and to reach potentially temperature levels in competition with much...

Selecting the best design options for turbo-expanders to be used in Organic Rankine Power Cycle applications is a difficult task, with special reference to the low-temperature applications (T150°C) which are relevant for specific fields in rapid development (geothermal binary plants, solar...

In this paper, a zero-dimensional model for the design of radial turbo-expanders for ORC applications is discussed, with special reference to the estimation of losses and efficiency; a comparison between different fluids (R134a, R1234yf, R236fa, R245fa, Cyclohexane, N-Pentane) is presented and...

The thermodynamics of compression and expansion processes in turbomachinery are examined. Rational efficiencies are defined and their relation to isentropic and polytropic efficiencies are discussed. Multistage turbines with extractions are optimized. This approach yields expressions that are...

Coal gasification is seen as an attractive way for hydrogen production. The main advantage of this approach is the low fuel price compared to reforming of natural gas. On the other hand, considering the EU climate policy, the emission of CO2 has to be reduced. The CO2 capture from the raw syngas...

In this paper an exergo-environmental analysis of a reverse osmosis desalination plant in Gran Canaria (Canary Islands, Spain) has been performed using real plant operation data. The plant has a nominal capacity of 82,000 m3/day. Different configurations are possible depending on the energy...

The stochastic nature of several renewable energy sources has raised the problem of designing and building storage facilities, which can help the electricity grid to sustain larger and larger contribution of renewable energy. Seawater pumped electricity storage is proposed as a good option for...

Application of a pipeline at the lower side of copper roofs to use them as solar collectors was investigated. An optimized module capable of converting a wide fraction of solar radiation into heat, and at the same time preserving the esthetic quality of the roof, was designed. Exergy analysis,...