Solar power enhances recovery in old oil fields

摘要

Eighteenth-century gentlemen scientists discovered that sunlight could produce remarkably high temperatures under the right circumstances. When light passed through glass, it could be trapped inside a box as heat. In the 1770s, a Swiss naturalist named Horace de Saussure built a sturdy wooden box, which he lined with black cork on the inside and packed with wool on the outside, then sealed the opening with three layers of glass. When angled toward the sun, the inside of the box heated quickly to well above the boiling point of water. Actually, as long ago as ancient Greece, scholars had found that parabolic mirrors, such as are used in Newtonian telescopes, could be made to boil water by focusing the sun's rays on a metal bucket. If the bottom of a reflective trough is parabola-shaped, the sun's heat can be focused on a pipe, in as long a length as you can build.