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I'm glad you raise this point. I think if we are going to stick huge solar farms in the desert we need to either (a) minimize the surface area (since it will be

I'm glad you raise this point. I think if we are going to stick huge solar farms in the desert we need to either (a) minimize the surface area (since it will become uninhabitable) and also figure out how to minimize the impact of thermal pollution on surrounding areas or (b) figure out how not to sterilize the area. Since I doubt anyone right now is in the mood for (b), I think we should be arguing strongly for (a). Thermal pollution on this scale is also going to cause local (or non-local) climate change, and we're going to need to deal with this at some point. There are no free lunches. The best way to get an extra kW is to save it by improving efficiency or not wasting it in the first place. (Just as it's almost certainly cheaper to prevent the Earth from getting fucked up, complete with deflecting asteroids, than it is to colonize Mars.) (Funnily enough, when I was designing a science fiction setting in the 1980s -- and of course like anyone paying attention I was already worried about global warming -- I posited that we'd be worrying about thermal pollution in the future. I thought we'd be using fusion power incredibly wastefully (flying cars, etc.) but life is always more complicated, and instead we're going to have thermal pollution from solar.)

JoeAltmaier 11y ago
Solar is doomed by that logic then. Because its effectiveness is exactly related to its physical and thermal footprint. We are already working on making the most of every square meter (conversion efficiency, concentrating the sunlight, using the most consistently-lit sites) so no help there. So if energy must be generated, a) is a lost cause. If this project is economically successful the next step is more desert consumed, and so on forever until its all gone.
- pjc50 11y ago
  Size of solar plant (from http://www.afdb.org/fileadmin/uploads/afdb/Documents/Environmental-and-Social-Assessments/Morocco_-_Ouarzazate_Solar_Power_Station_Project_II_-_ESIA_Summary.pdf http://www.afdb.org/fileadmin/uploads/afdb/Documents/Environ... ): 3000ha, or 30km^2 Size of Sahara desert: 9,400,000km^2 I make that 0.00032% of the desert consumed.
pjc50 11y ago
Care to put some magnitude numbers on that "thermal pollution" effect? How does it compare to, say, the emission of warm water from conventional power plants into the marine environment? Or urban heat islands? How is the albedo of the plant versus that of the existing terrain? I'm also confused about the idea of a desert "becoming" uninhabitable. The whole discussion reminds me of people talking about bird death effects only related to wind power, ignoring all other environmental and man-made causes. I do accept that the desert is an ecosystem of its own and the usual checks should be made that you're not eradicating the sole habitat of an endangered species. Edit: there's even an environmental impact check in that EISA PDF from my other comment. The Ouarzazate solar complex study area is not part of any protected natural zone; however, the following are located on its outlying zones: The Mansour Ed Dahbi artificial lake, part of RAMSAR (site of the dam – located 6 km South of the site); The Bouljir dorcas gazelle reserve (13 km to the North-West of the site); The Iguernane Reserve (15 km to the North–West of the site); The key site of Sbaa Chaab (20 km East of the site); The Biosphere Reserve (solar complex in buffer zone B of the Biosphere Reserve). None of the plant species found in the project site and its environs is considered rare or endangered. The solar complex project site is considered to be of low heritage value. The areas with high heritage value are located on the eastern and western reaches of the project site.
- JoeAltmaier 11y ago
  That's exactly the misconception folks have about desert right there, in that quoted "becoming". The idea is that deserts are worthless, containing no life. Probably because they contain nothing that humans value for their own comfort. Yet deserts have lots of life, unique life, that because of the harsh environment is exquisitely tuned to the desert environment. This is the stuff that will be lost if the sunlight is gone, the heat goes away, the moisture balance is upset by so much shade. Plentiful shade and cool and wet are good for people; disaster for the desert ecosystem. The 'thermal pollution' is, curiously, cooling instead of heating in this case. Light is turned to electricity instead of falling on the ground and becoming heat.
  - azinman2 11y ago
    We need it to counteract global warming
upofadown 11y ago
The ground absorbs most of the solar radiation anyway. So having some of that radiation hit some black pipes is not going to change the amount of heat generated in any significant way. So you need to explain what you mean by "thermal pollution".
- Tloewald 11y ago
  The albedo (reflectivity) of typical desert landscape is going to be higher than that of solar collectors (which, by definition, are trying to collect sunlight). Large cities, which are not specifically trying to collect sunlight, already have climatic effects (because they absorb more heat). I'm not down on solar, just pointing out it has its own potential downsides which shouldn't be ignored.

JoeAltmaier 11y ago

Solar is doomed by that logic then. Because its effectiveness is exactly related to its physical and thermal footprint. We are already working on making the most of every square meter (conversion efficiency, concentrating the sunlight, using the most consistently-lit sites) so no help there. So if energy must be generated, a) is a lost cause. If this project is economically successful the next step is more desert consumed, and so on forever until its all gone.

pjc50 11y ago
Size of solar plant (from http://www.afdb.org/fileadmin/uploads/afdb/Documents/Environmental-and-Social-Assessments/Morocco_-_Ouarzazate_Solar_Power_Station_Project_II_-_ESIA_Summary.pdf http://www.afdb.org/fileadmin/uploads/afdb/Documents/Environ... ): 3000ha, or 30km^2 Size of Sahara desert: 9,400,000km^2 I make that 0.00032% of the desert consumed.

pjc50 11y ago

Care to put some magnitude numbers on that "thermal pollution" effect? How does it compare to, say, the emission of warm water from conventional power plants into the marine environment? Or urban heat islands? How is the albedo of the plant versus that of the existing terrain? I'm also confused about the idea of a desert "becoming" uninhabitable. The whole discussion reminds me of people talking about bird death effects only related to wind power, ignoring all other environmental and man-made causes. I do accept that the desert is an ecosystem of its own and the usual checks should be made that you're not eradicating the sole habitat of an endangered species. Edit: there's even an environmental impact check in that EISA PDF from my other comment. The Ouarzazate solar complex study area is not part of any protected natural zone; however, the following are located on its outlying zones: The Mansour Ed Dahbi artificial lake, part of RAMSAR (site of the dam – located 6 km South of the site); The Bouljir dorcas gazelle reserve (13 km to the North-West of the site); The Iguernane Reserve (15 km to the North–West of the site); The key site of Sbaa Chaab (20 km East of the site); The Biosphere Reserve (solar complex in buffer zone B of the Biosphere Reserve). None of the plant species found in the project site and its environs is considered rare or endangered. The solar complex project site is considered to be of low heritage value. The areas with high heritage value are located on the eastern and western reaches of the project site.

JoeAltmaier 11y ago
That's exactly the misconception folks have about desert right there, in that quoted "becoming". The idea is that deserts are worthless, containing no life. Probably because they contain nothing that humans value for their own comfort. Yet deserts have lots of life, unique life, that because of the harsh environment is exquisitely tuned to the desert environment. This is the stuff that will be lost if the sunlight is gone, the heat goes away, the moisture balance is upset by so much shade. Plentiful shade and cool and wet are good for people; disaster for the desert ecosystem. The 'thermal pollution' is, curiously, cooling instead of heating in this case. Light is turned to electricity instead of falling on the ground and becoming heat.
- azinman2 11y ago
  We need it to counteract global warming

upofadown 11y ago

The ground absorbs most of the solar radiation anyway. So having some of that radiation hit some black pipes is not going to change the amount of heat generated in any significant way. So you need to explain what you mean by "thermal pollution".

Tloewald 11y ago
The albedo (reflectivity) of typical desert landscape is going to be higher than that of solar collectors (which, by definition, are trying to collect sunlight). Large cities, which are not specifically trying to collect sunlight, already have climatic effects (because they absorb more heat). I'm not down on solar, just pointing out it has its own potential downsides which shouldn't be ignored.