Solar thermal energy array and drive

Abstract

Disclosed are systems and methods for controlling arrays of solar thermal energy collectors. Rows of the array are actuated sequentially or consecutively rather than concurrently.

1 . A solar thermal energy collector array comprising
 a) a plurality of rows of solar thermal energy collectors comprising a first solar thermal energy collector row and a second solar thermal energy collector row,   b) a plurality of electric motors comprising a first motor configured to position the first solar thermal energy collector row and a second motor configured to position the second solar thermal energy collector row,   c) a plurality of inclinometers comprising a first inclinometer and a second inclinometer, the first inclinometer being coupled with the first solar thermal energy collector row and the second inclinometer being coupled with the second solar thermal energy collector row,   d) a row controller in communication with the plurality of electric motors and the plurality of inclinometers, the row controller being configured to sequentially actuate
 i) the first motor to position the first solar thermal energy collector row according to a position of the first solar thermal energy collector row as indicated by the first inclinometer, and 
 ii) the second motor to position the second solar thermal energy collector row according to a position of the second solar thermal energy collector row as indicated by the second inclinometer. 
   
     
     
         2 . An array according to  claim 1  wherein the row controller comprises a field-mounted enclosure in the immediate vicinity of the plurality of rows. 
     
     
         3 . An array according to  claim 1  and further comprising a central controller in communication with the row controller, the row controller being configured to calculate a setpoint for the row controller and the central controller not being configured to calculate a setpoint for the row controller. 
     
     
         4 . An array according to  claim 3  wherein the central controller is configured to provide an instruction to the row controller to position the rows controlled by the row controller to a position selected from a stow, track, lag, defocus, and wash position. 
     
     
         5 . An array according to  claim 4  wherein the central controller is configured to provide said instruction in response to a temperature of a working fluid in said array. 
     
     
         6 . An array according to  claim 4  wherein the central controller is configured to provide said instruction in response to a weather sensor. 
     
     
         7 . An array according to  claim 4  wherein the central controller is configured to provide said setpoint in response to a signal indicative of an operating condition of said facility that extracts work from heated working fluid of said array. 
     
     
         8 . An array according to  claim 1  and further comprising a central controller in communication with the row controller, the central controller being configured to provide a setpoint representative of row angle to the row controller. 
     
     
         9 . An array according to  claim 8  wherein said setpoint representative of row angle is sufficient to place the rows controlled by the row controller to a position selected from a stow, track, lag, defocus, and wash position. 
     
     
         10 . An array according to  claim 9  wherein the central controller is configured to provide said setpoint in response to a temperature of a working fluid in said array. 
     
     
         11 . An array according to  claim 9  wherein the central controller is configured to provide said setpoint in response to a weather sensor. 
     
     
         12 . An array according to  claim 9  wherein the central controller is configured to provide said setpoint in response to a signal indicative of an operating condition of said facility that extracts work from heated working fluid of said array. 
     
     
         13 . An array according to  claim 1  wherein the plurality of rows comprises a number of rows, said number being at least five, the plurality of electric motors comprises at least said number of motors respectively coupled to said rows, the plurality of inclinometers comprises at least said number of inclinometers respectively coupled to said rows, and said row controller is configured to sequentially but not simultaneously actuate any of said number of motors. 
     
     
         14 . An array according to  claim 13  wherein said number is at least ten. 
     
     
         15 . An array according to  claim 13  wherein said number is at least fifteen. 
     
     
         16 . An array according to  claim 1  wherein the solar thermal energy collectors are trough collectors. 
     
     
         17 . An array according to  claim 16  wherein the trough collectors each have a chain and sprocket drive coupling the electric motors and the collector troughs. 
     
     
         18 . An array according to  claim 16  wherein the trough collectors each have an aperture less than about 3 meters. 
     
     
         19 . An array according to  claim 18  wherein the aperture is less than about 2 meters. 
     
     
         20 . A method of positioning a plurality of rows of a solar thermal energy trough collector array comprising sequentially and not simultaneously positioning any of the number of rows of the array, the number being at least two. 
     
     
         21 . The method of  claim 20  wherein the number is at least five. 
     
     
         22 . The method of  claim 20  wherein the number is at least ten. 
     
     
         23 . A method according to  claim 20  wherein the rows are positioned consecutively.