Following 535 MWe parabolic trough systems supposed to be built by Israeli Solel Solar Systems (if they succeed to join forces with the right strategic partners and raise the required 2BnUSD), and about 500MWe Power Towers systems to be built by BrightSource -LuzII (if they succeed to build their first pilot plant to provide heat from the sun, early next year), and the today announced 177MWe deal based on Ausra Inc.’s linear fresnel reflectors, – it seems that parabolic dish and/or CPV are in line.
It is understandable why PG&E decided on the parabolic trough systems, as they are considered commercially available, and Solel has the know-how of the primary developers of this technology. Moreover, Solel, did not rest on Luz’s laurels, and enhanced the performance of their linear receivers. However, it seems that they have already pushed the envelope of these single-axis trackers….….. and does not have the long term commercial potential.
Until lately it was taken for granted that troughs and towers were having potential advantage for providing electric power to utilities, having high dispatchability capabilities, that gives them the ability to more closely match the utility load profile, over dish and CPV systems, which were having potential advantage for decentralized energy and mainly for remote areas, due to their modularity.
It seems that the coast is clear now for solar systems based on dish with high concentrators, based on enhanced two-axis tracking systems and with inherent storage and hybrid fossil capabilities. The remaining question is what will the PCU be based on? There are no operating commercial dish-Stirling power plants; from the development of viable Stirling engines there is ‘nothing to write home about’; and storage is currently not a considered viable option for dish-Stirling. Hence, it seems that there is room for PCU based on CPV or an innovative receiver feeding a gas/air turbine with very high temperature flux.
Moreover, there is room for doubt if all the above three – Solel’s trough, Ausra’s Fresnel and Bright Source’s towers – will really get under way in due time and provide electricity to PG&E as soon as 2010 (as suppliers claim).
Hence, Solar Dish, high temperatures receivers and CPV providers – buckle down!
