What is the efficiency of parabolic trough collector?
The parabolic trough collector (PTC) technology is the most recognized in solar concentration technique and offers good thermal efficiency up to 400° C [3] while the reflectivity of parabolic through consists of aluminum or polished glass could reach 88.5% or 95%, respectively [16].
What is the efficiency of parabolic?
The process is economical and, for heating the pipe, thermal efficiency ranges from 60-80%. The overall efficiency from collector to grid, i.e. (Electrical Output Power)/(Total Impinging Solar Power) is about 15%, similar to PV (Photovoltaic Cells) but less than Stirling dish concentrators.
What is the efficiency of parabolic dish collector?
Within CSP technologies, parabolic dish concentrators are the most efficient of all solar collector types due to a combination of dual axis tracking and high concentration ratios [2]. The optical efficiencies noted for different dish concentrators range from 78% to 89% [3].
What is the function of a parabolic trough?
The parabolic trough reflector is a solar thermal energy collector designed to capture the sun’s direct solar radiation over a large surface area and focus, or more generally “concentrate it” onto a small focal point area increasing the solar energy received by more than a factor of two which means more overall heat …
Which is the advantage of parabolic trough system?
The low cost provided by parabolic troughs is the greatest advantage. The cheapest source at present is solar parabolic troughs. Considerable working experience has been gained from their working over the years. Parabolic troughs generate very high temperatures which are suitable for steam generation.
What is optical efficiency?
The optical efficiency (dimensionless) of a receiver tube is defined as the fraction of the incident solar radiation energy on the glass cover which is transferred to a heat transfer fluid as thermal energy inside the absorber tube [10].
What is difference between parabolic trough and parabolic dish?
Parabolic trough is a line focus system which concentrate the heat of the sun on a series of long tube called heat collecting element whereas parabolic dish is a point focus system that uses a prabolic shaped reflector to focus on single point.
What is the main disadvantage of parabolic trough reflector?
Disadvantages: Sun tracking is necessary to maintain solar collection by parabolic troughs otherwise the output will reduce. This increases cost and maintenance associated in maintaining the moving structures. High concentrated sunlight is essential for good working of a parabolic trough.
What is the purpose of parabolic dishes?
Parabolic dish systems use mirrors that are mounted over a parabolic-shaped dish to focus the sun’s rays onto a receiver. The latter is mounted at the focal point of the dish along with a heat engine (Stirling or Brayton cycle engine), which has thin tubes inside it.