Answer: About 12.5% of the Sonora Desert, or 15,000 square mile/9.5 million acres. Compare this to the 450 million acres currently used as crop land (the majority of which is irresponsibly and inefficiently used for animal feed--more on the gross inefficiency of meat production compared to vegetable/grain production for human comsumption in a later post) and 500 million acres used as grazing land!! I already posted this statistic, but found a link that explains the calculations . . .
Link to the calculations and statistics:
In response to any concerns about the potential environmental impact of these algae farms, consider that the apparatuses necessary to produce the algae could be built where little to no foliage is currently existing, and would actually provide shade to create habitat for many desert dwelling species. And also consider that the toxicity of biodiesel (b100) is negligible, whereas diesel and gasoline are both highly toxic and pose long term hazards to plant, animal and human life.
The magic of mirrors . . . most of us gaze into these reflective surfaces every day to do hair, brush teeth, and get presentable for a day at work or school. They allow astronomers to gaze deep into space, give drivers a rear-view, and now with centuries-old technology, with some new innovations, mirrors could generate enough electricity to power the whole country by utilizing a combined area of only 92 miles by 92 miles!!! That's only twice the size of the county I currently abide in (Albany County, Wyoming)!!! This is also similar to the area that is currently being heavily disturbed and significantly impacted by coal mines in this country.
Obviously these fields of mirrors would be spread across the country, minimizing any environmental impact, but this would entirely do away with the need for the excessively destructive practices of coal mining, natural gas production, etc., etc., to meet the current electricity needs of the United States!!!! Not to mention that this process would absord some degree of the sun's radiation, thus aleviating some degree of the greenhouse effect!!
The only potential environmental hazard would be birds running into the mirrors, though with some ingenuity and research there should be some means of preventing the inadvertant avian kamakazes from mistaking the mirrors for open sky, else the warped reflection would be deterant enough.
Check out this article, which gives a breakdown of this land area, and some other facts regarding this amazing energy technology:
YEAH, BUT WHAT ABOUT CARS AND TRUCKS AND TRAINS?
Insofar as liquid fuel for automobiles and trains, Biodiesel produced from algae could supply the nations need for diesel fuel with only 125 miles by 125 miles of Southwestern desert with current technology (12.5% of the Sonoran Desert's landmass).
Healthy and sustainable answers for our world and environment are there!! Now let's make it happen!!!