System Designs
During the day the sun has different positions. For low concentration systems (and low temperatures) tracking can be avoided (or limited to a few positions per year) if nonimaging optics are used. For higher concentrations, however, if the mirrors or lenses do not move, then the focus of the mirrors or lenses changes (but also in these cases nonimaging optics provides the widest acceptance angles for a given concentration). Therefore it seems unavoidable that there needs to be a tracking system that follows the position of the sun (for solar photovoltaic a solar tracker is only optional). The tracking system increases the cost and complexity. With this in mind, different designs can be distinguished in how they concentrate the light and track the position of the sun.
Read more about this topic: Solar Thermal Energy, High-temperature Collectors
Famous quotes containing the words system and/or designs:
“Television is an excellent system when one has nothing to lose, as is the case with a nomadic and rootless country like the United States, but in Europe the affect of television is that of a bulldozer which reduces culture to the lowest possible denominator.”
—Marc Fumaroli (b. 1932)
“He began therefore to invest the fortress of my heart by a circumvallation of distant bows and respectful looks; he then entrenched his forces in the deep caution of never uttering an unguarded word or syllable. His designs being yet covered, he played off from several quarters a large battery of compliments. But here he found a repulse from the enemy by an absolute rejection of such fulsome praise, and this forced him back again close into his former trenches.”
—Sarah Fielding (1710–1768)