I said it "could be." never said it will.
An average worker in such an industry makes over $100k in salary and benefits in California. The project will cover 7,025 acres, or 11 square miles. The parabolic reflectors will require daily cleaning to keep dust from reducing the thermal efficiency. How many people will it take, and at what cost of resources?
Now I can wag it at about 2500 or more employees performing daily maintenance. Since this isn't exactly a skilled job, let's assume they make $60k in salary and benefits. That amounts to about $150 million annual costs just for labor. What about the costs of the specialized cleaning equipment, supplies, fuel, etc.
I based the approximate 7025 acres at 2 manhours of labor a day per acre. I allotted each employee with 1904 annual hours. 2080 hours minus 4 weeks annual vacation - 16 hours average sick leave. Use your own numbers as you wish and ratio them with my 1904, pay, and man-hours per acre. Annual maintenance is 5,128,250 man-hours. At 1904 hours per man, that's 2693 employees.
I'm all ears for what you think the true costs will be.