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:
“Intimately concerned as we are with the system of Europe, it does not follow that we are therefore called upon to mix ourselves on every occasion, with a restless and meddling activity, in the concerns of the nations which surround us.”
—George Canning (1770–1827)
“My own thoughts
Are my companions; my designs and labors
And aspirations are my only friends.”
—Henry Wadsworth Longfellow (1807–1882)