Cost of dispatchable electricity from concentrated solar power, solar tower plants, with 10 hours’ molten salt thermal energy storage

Mechanical Engineering Department, College of Engineering, Prince Mohammad Bin Fahd University, Al Khobar, Saudi Arabia

^* Corresponding author: a.a.boretti@gmail.com

Abstract

While there is a consensus that concentrated solar power solar tower plants with thermal energy storage 10 hours may permit the production of dispatchable electricity at 6 c/kWh, without a single plant utility size produced and operated featuring this technology at this cost, the recent experience of Crescent Dunes has clearly shown that this is not the case. Crescent Dunes started operation in October 2015 demonstrating since the very beginning the lack of maturity of this specific technology, with lack of production or no production at all, every single month since then. As the 110 MW plant of cost about 1 billion $ US has been shut down after less than 4 years of operation, and a total production of only 418, 849 MWh, that is less than the 500, 000 MWh expected every year for 25 years, this translate in a total cost, excluding repairs and maintenance costs incurred in the 4 years, of 2.38 $ per kWh of unpredictable electricity. This experience suggests that every estimation of costs and performances should be based on data of plants built and operated, and to avoid the use of models not yet validated to predict performances of novel plants. There is a mature solar thermal technology, and this is the parabolic trough.