"The next step up from hydroponics is the orbital space farm, as envisaged by artist Frank Tinsley in 1954. The great coils you see in the giant dish contain chlorella algae; the wonder food of Future Past that was, along with yeast, supposed to replace bread as the staple of all mankind.
Back in the 1950s, this didn't seem like such a crazy idea. On paper, chlorella looked like a winner. Not only was the microorganism 50 percent protein with the complete set of amino acids, but it was also chock full of calories, fats and vitamins. Furthermore, all you needed to grow it was sunshine, water and carbon dioxide. And it grew in incredible quantities with one pilot plant projecting yields of 40 tons of dry weight protein per acre. At this rate, a farm the size of Rhode Island would feed the entire planet and cultivating one fifth of the Earth's surface would not only provide food, but all of the fuels needed for every major industry on the planet. All that needed to be overcome were "minor technical difficulties."...
