get the job done. Solar mechanical power production in the late nineteenth and early twentieth centuries did not meet either criterion. Despite warnings from noted scientists and engineers, alternatives to what seemed like an inexhaustible fuel supply did not fit into the U.S. agenda. Unfortunately, in many ways, these antiquated sentiments remain with us today. During the 1970s, while the OPEC nations exercised their economic power and as the environmental and "no-nuke" movements gained momentum, Americans plotted an industrial coup whose slogans were energy efficiency and renewable resources. Consequently, mechanical solar power--along with its space-age, electricity-producing sibling photovoltaics, as well as other renewable sources such as wind power--underwent a revival. And during the next two decades, solar engineers tried myriad techniques to satisfy society's need for power.They discovered that dish-shaped reflectors akin to Mouchout's and Eneas's designs were the most efficient but also the most expensive and difficult to maintain. Low-temperature, nonconcentrating systems like Willsie's and Tellier's, though simple and less sensitive to climatic conditions, were among the least powerful and therefore suited only to small, specific tasks. Stationary reflectors like those used in Adams's device, now called Power Tower systems, offered a better solution but were still pricey and damage prone.By the mid-1980s, contemporary solar engineers, like their industrial-revolution counterparts Ericsson and Shuman, determined that for sunny areas, tracking parabolic troughs were the best compromise because they exhibited superior cost-to-power ratios in most locations. Such efforts led engineers at the Los Angeles-based Luz Co. to construct an 80-megawatt electric power plant using parabolic trough collectors to drive steam-powered turbines. The company had already used similar designs to build nine other solar electric generation facilit...
