Describir: Flat plate collectors :

 _    _     ______   _    _     _____    _____     _    _     _____   
| |  | ||  /_   _// | |  | ||  |  ___|| |  __ \\  | || | ||  / ____|| 
| |/\| ||   -| ||-  | |/\| ||  | ||__   | |  \ || | || | || / //---`' 
|  /\  ||   _| ||_  |  /\  ||  | ||__   | |__/ || | \\_/ || \ \\___   
|_// \_||  /_____// |_// \_||  |_____|| |_____//   \____//   \_____|| 
`-`   `-`  `-----`  `-`   `-`  `-----`   -----`     `---`     `----`  
                                                                      
   ___    
  / _ \\  
 | / \ || 
 | \_/ || 
  \___//  
  `---`