renewable electricity production
thermochemical cycle allowing to store energy in the form of solid sulphur
PEGASUS will investigate a novel power cycle for renewable electricity production combining a solar centrifugal particle receiver with a sulphur storage system for baseload operation. The proposed process combines streams of solid particles as heat transfer fluid (proppant) that can also be used as catalyst in the framework of a thermochemical cycle allowing to store energy in the form of solid sulphur, rendering thus a solar power plant capable of round-the-clock renewable electricity production.
Pegasus project has the following main objectives:
Improve proppant properties as thermal fluid and SO3-splitting oxide catalysts synthesizing particles performing conversion exceeding 65% of the thermodynamic value; deactivation along first 1000 hours of exposure to reaction conditions lower than 15 %, characterized by a solar absorptivity higher than 0.85 with cost lower than 1€/MWhth.
Demonstrate particles performance in a prototype 500 kWth centrifugal particle solar receiver for heating such particle streams to temperatures in excess of 900°C and assure storage capacity for at least 6 hours.
Design, build and operate a prototype 50kWth sulphuric acid decomposition cascade consisting of an SO3 decomposer and a H2SO4 evaporator/heat exchanger using moving heated proppant particles as the heat source.
Demonstrate sulphuric acid decomposer technology on a 500kWth-scale operating it in a closed-loop assembly with the centrifugal particle solar receiver, under real solar irradiation achieving sulphuric acid decomposition with more than 40 % reactor efficiency.
Develop and realize a novel lab-scale sulphur burner able to modulate in a range of 10-50 kWth with combustion efficiency higher than 99%, power densities higher than 1,5 MW/m3 and flame temperatures higher than 1400°C.
Demonstrate the feasibility of the over-all proposed process on a scaled-up 5MWth power level, assess the technology vs. the targets set and evaluate its potential with respect of realizing a sulphur storage cycle enabling solar power production at a LCOE of 0.08 €/kWh.