Harnessing the Sahara

This sounds like the power of recycling; the same concept occurred a month or two ago.

The main problems associated with solar farms in the dessert are wind blown sand plus high day time and low night time temperatures.

A light dust deposited on the surface of the cells can reduce output by up to 30% and the abrasive nature of sand will quickly erode the cell (or a thin glass covering over the cell) and the support frames.

The high ambient day time temperature will reduce both performance of the cell and the cell life. Typically cells degrade over a 4-6 year period. Assume on reducing this to 30 months maximum.

The differential between day and night time temperature causes a lot of expansion and contraction, leading to joint failures and circuit breakdowns. The oil industry deals with this problem by heating electrical cabinets overnight and cooling them in the daytime. Heating a complete solar array may be less practical.

High light levels are no substitute for pointing the arrays directly towards the sun. Typical performance increase for sun follow arrays over fixed arrays are 25-35%. My company has developed a low cost, low tech solution for large sun follower arrays that can be built and maintained in the third world. It is more robust than anything else on the market but we would not recommend it for Saharan conditions.

Finally, processing silicon requires temperature controlled clean room conditions and highly skilled labour. The Sahara dessert is not the place I would choose to set up and run a clean room, or recruit, retain and house a specialised workforce.

why would anyone want to put that kind of power generation in that location anyway?

scottymac

It depends on the quality of the sand, for example, how much of the Sahara sand is Silica (Si O2)?

Most sand that I have been in contact with is a mixture of Quartz and Feldspars plus a little iron oxide, and if the sand in the Sahara is such then it will be totally useless?

Xanasax