Solar panels and mirrors need to be cleaned almost daily if efficiencies are to stay where they need to be. Dust is not transparent, so even just one gram of dust per square meter of solar panel area can reduce efficiency by around 40 percent<http://www.tandfonline.com/doi/abs/10.1080/14786450500291834#.UbIQLWRATzc>. At that rate, it doesn't take long in a dusty desert for the problem to become intractable.
In the desert near Abu Dhabi in the United Arab Emirates the Middle East's first large CSP plant recently faced down the dust issue. In order to reach the 100-megawatt-capacity goal of the Shams 1 plant, developers had to add substantially more mirrors<http://www.bloomberg.com/news/2010-10-27/dust-blocking-sun-s-rays-at-solar-plant-in-uae-masdar-official-says.html> to the plant than planned due to dust in the atmosphere. Scott Burger<http://www.greentechmedia.com/research/analysts>, an analyst at Greentech Media's GTM Research who focuses on the region, said the plant probably ended up costing three times the initial estimate, thanks in part to dealing with that dust. And now that it is built, Shams 1 sends a series of trucks<http://spectrum.ieee.org/energywise/green-tech/solar/how-do-you-clean-258048-solar-thermal-mirrors-trucks-with-robot-arms> up and down the lines of 250,000 mirrors every day, using robot arms to spray that precious water and clean away the dust. On Wed, Mar 5, 2014 at 10:36 AM, ChemE Stewart <[email protected]> wrote: > Steam Boilers, Steam Turbines and flat mirrors are a matured technology, > have been in use for 100 years > > > On Wed, Mar 5, 2014 at 10:34 AM, Jed Rothwell <[email protected]>wrote: > >> ChemE Stewart <[email protected]> wrote: >> >> >>> 400 MW Natural Gas plant would cost $400M VS. $2.2b with much less >>> equipment and would generate CO2 to feed the trees. :) >>> >> >> On the other hand, over the life of a natural gas plant you have to pay >> for a lot of gas, whereas sunlight is free. >> >> $2.2 billion is a lot of money, but the cost should fall if the >> technology continues to be developed. It comes to $5.5 per gigawatt. That >> is cheaper than nuclear power. The Southern Company is now building two >> nuclear plants, for a total of 2 GW I think. The cost is $14 billion, $7 >> billion per GW: >> >> >> http://online.wsj.com/news/articles/SB10001424052748704804204575069301926799046 >> >> That is despite the fact that nuclear power has been developed for 60 >> years. Plus nuclear uranium fuel does cost something, albeit less than coal >> or gas. >> >> - Jed >> >> >
