Design of Heliostat Field for an Unfired Solarized Micro Gas Turbine in a Closed Cycle with Mass Flow Control Regulation

Design of Heliostat Field for an Unfired Solarized Micro Gas Turbine in a Closed Cycle with Mass Flow Control Regulation

Francesco RovenseMaria Speranza Bomentre Manuel Antonio Silva Perez Vittorio Ferraro Mario Amelio 

Department of Mechanical, Energy and Management Engineering, University of Calabria, Via P. Bucci Edificio Cubo 46 C, 87063, Arcavacata di Rende (CS) Rende, Italy

Department of Energy Engineer, Escuela Técnica Superior de Ingeniería Universidad de Sevilla, Camino de los Descubrimientos, s/n. 41092 Sevilla, Spain

Corresponding Author Email:
18 March 2018
28 May 2018
30 September 2018
| Citation



Interest in smart networks has increased over the past decade. One of the main advantages is the possibility of producing electricity on site and autonomously. In this scenario, small or very small generators, installed near of the places of consumption, play a fundamental role. A real possibility is offered by the Micro Gas Turbine (MGT). Such a machine has the possibility to follow the electric load of the network and is also suitable to use solar energy as a source of heat in the cycle, through the concentration of direct normal radiation (DNI). With the solar power supply, the regulation capacity of the MGT can be exploited in order to convert all the thermal power collected.

In this work, the solar field, of an unfired closed solarized micro gas turbine employing air as working fluid with mass flow control system, has been analyzed. The mass flow control system is able to adjust the mass flow rate by means of a variation in density, to control the turbine inlet temperature (TIT), as the incoming thermal power varies. The volumes of the engine, as well as the speed triangles, do not change; therefore, by keeping a TIT constant, it is possible to control the power production, according to the incident solar radiation, without a degradation of efficiency. The concentrating solar tower and receiver systems are able to produce thermal power suitable in MGT and in this case represent the only one heat source. The heliostats field control system operates together with the mass flow one, so the optimization of the solar field plays a fundamental role in controlling the TIT and increasing the energy production. This article illustrates the study of the heliostat field suitable for the aforementioned control system. Different heliostats size and solar multiple (SM) have been taken in to account to choose the best configuration of the solar field. The analysis has been carried out by the open source Solar PILOT, while the weather data of Seville town have been considered. The results show that the heliostats field best configuration allows getting a substantial energy production and let to adjust the solar flux precisely in order to control, with the mass flow control system, the TIT.


concentrating solar power, micro gas turbine, CSP, control system, heliostats

1. Introduction
2. Methodology
3. Results
4. Conclusions

Special thanks to Matteo Gallina for his precious support and to researchers of the Thermodynamics Department of University of Seville for their essentials suggestions.


[1] Noussan M, Roberto R, Nastasi B. (2018). Performance indicators of electricity generation at country level—the case of Italy. Energies 11(650).

[2] Ferraro V, Mele M, Marinelli V. (1975). Sky luminance measurements and comparisons with calculation models 73(13): 1780-1789.

[3] De Rosa A, Ferraro V, Kaliakatsos D, Marinelli V. (2008). Calculating diffuse illuminance on vertical surfaces in different sky conditions. Energy 33(11): 1703-1710.

[4] Lo Basso G, Nastasi B, Salata F, Golasi I. (2017). Energy retrofitting of residential buildings—How to couple combined heat and power (CHP) and heat pump (HP) for thermal management and off-design operation. Energy and Buildings 151: 293-305.

[5] Castellani B, Gambelli AM, Morini E, Nastasi B, Presciutti A, Filipponi M, Nicolini A, Rossi F. (2017). Experimental investigation on CO2 methanation process for solar energy storage compared to CO2-based methanol synthesis. Energies 10(855).

[6] Rovense F. (2015). A case of study of a concentrating solar power plant with unfired Joule-Brayton cycle. Energy Procedia 82: 978–985.

[7] Rovense F, Amelio M, Scornaienchi NM, Ferraro V. Performance analysis of a solar-only gas micro turbine, with mass flow control. Energy Procedia 126: 675–682.

[8] Rovense F, Amelio M, Ferraro V, Scornaienchi NM. (2016). Analysis of a concentrating solar power tower operating with a closed joule Brayton cycle and thermal storage. International Journal of Heat and Technology 34(3): 485-490.

[9] Noussan M, Nastasi B. (2018): Data analysis of heating systems for buildings—a tool for energy planning, policies and systems simulation. Energies 11(233).

[10] Rovense F, Perez MS, Amelio M, Ferraro V, Scornaienchi NM. (2017). Feasibility analysis of a solar field for a closed unfired Joule-Brayton cycle 35(Sp.1): S166-S171.

[11] Amelio M, Beraldi P, Ferraro V, Scornaienchi M, Rovense F. (2016). Optimization of heliostat field in a thermal solar power plant with an unfired closed Joule-Brayton Cycle. Energy Procedia 101: 472-479.

[12] Saito H, Latcovich J, Fusselbaugh M, Dinets M, Hattori K, Sakaki N. (2003). Microgas Turbine, Risks and Markets, IMIA Conference, Stockholm- September 2003.

[13] Technical Description T100 Natural Gas, T100 micro turbine system; D 14127-03 Version 3 09/12/29.

[14]  AORA Tulip, Joining hands through sustainable energy for sustainable livelihoods; Overview of the Technology Solution. User Guide, 2016.

[15] Moreno TS. (2016). Solar resource assessment in Seville, Spain, statistical characterisation of solar radiation at different time resolutions. Solar Energy 132: 430-441. 

[16] Segal A, Epstein M. (2001). The optics of the solar tower reflector. Solar Energy Supplement 6(69): 229-241.

[17] Téllez F, Burisch M, Villasente, Sánchez M, Sansom C, Kirby P, Turner P, Caliot C, Ferriere A, Bonanos CA, Papanicolas C. Montenon A, Monterreal R, Fernández J. (2014). State of the Art in Heliostats and Definition of Specifications, STAGE STE Projec, Deliverable 12.

[18] Ávila-Marín AL. (2011). Volumetric receivers in solar thermal power plants with central receiver system technology. Solar Energy 85(5): 891-910.

[19] Gomez-Garcia F, González-Aguilar J, Olalde G, Romero M. (2016). Thermal and hydrodynamic behaviour of ceramic volumetric absorbers for central receiver solar power plants: A review.

[20] Grobler A, Gauché P. (2014). A Review of Aiming Strategies for Central Receivers, in Proceedings of the second, Southern African Solar Energy Conference, Port Elizabeth, South Africa, 2014.