Thermal performance prediction of a solar hybrid gas turbine

The present work focuses on a modelling procedure to simulate the operation of a solar hybrid gas turbine. The method is applied to a power generation system including an heliostat field, a receiver and a 36 MW commercial gas turbine. Heat is provided by concentrated solar power and integrated by fossil fuel. A detailed modelling of the gas turbine (GT) is proposed to predict the performance of commercial GT models in actual operating conditions. Advanced software tools were combined together to predict design and off-design performance of the whole system: TRNSYS® was used to model the solar field and the receiver while the gas turbine simulation was performed by means of Thermoflex®. A detailed comparison between the solarized and the conventional gas turbine is reported, taking into account GT electric power, efficiency and shaft speed. All thermodynamic parameters such pressure ratio, air flow and fuel consumption were compared. The main advantage of solarization is the fossil fuel saving, but it is balanced by a relevant penalty in power output and efficiency.

► A solar hybrid gas turbine (GT) was modeled in off design conditions.
► A commercial two-shaft GT was chosen because of the complex regulation.
► Performance of the solar hybrid GT were compared against the pure fossil GT.
► Solarization gives rise to a reduction in GT power output and electric efficiency.