1. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left and middle: horizontal primary axes and linear drives [37], left autonomous [5]; right: multilever heliostat [47]

2. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left: elevation axis at ground level, linear and rim drive, small extra mirror for off-set correction [43]; middle: big carousel type heliostat with framework pylon [21]; right: ground anchor, framework pylon and cable drives [20]

3. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left: locking of elevation drive during stow (for locking the black bolt is positioned by the azimuth drive into the gray cramp) and framework facets; middle: concrete heliostat; both seen at Themis solar power plant; right: Yoke [61]

4. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left: pretensioning of azimuth drive via spring to reduce impact of back lash; right: elevation axis between torque tube and mirrors to avoid huge bearings around continuous torque tube and to reduce lever arm of gravity loads of mirror panel [17]

5. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left and middle: rotation by variation of center of gravity by water channel system [6], if rolling on ground (left) no locking of orientation is possible and high mass would be needed for wind load resistance; right: hydraulic drive with fluid containers [18] (no test results known)

6. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left: inflatable heliostat [41]; right: target aligned heliostat with ganged facets [48]

7. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Left: ganged normal vectors: ends of parallel orange vectors to the sun move on spherical shapes. The blue normal vectors of the mirror planes are fixed to the green vectors to the receiver and to the ends of the orange sun vectors and can be connected by a horizontal rod (blue) to realize ganged normal vectors (compare Ref. [29]); right: ganged heliostats according to Ref. [30] (not tested yet).

8. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Rim drives; left and middle: with vertical primary axis and suspension of mirror facets [65] (left) or with stretched membrane, chain-rims and suspension of rim of secondary axis [64] (middle); right: with horizontal primary axis [10] (not tested yet)

9. From: Survey of Heliostat Concepts for Cost Reduction
Date of download: 10/28/2017
Copyright © ASME. All rights reserved.
From: Survey of Heliostat Concepts for Cost Reduction
J. Sol. Energy Eng. 2013;136(1): doi: /
Figure Legend:
Approaches for lowering mirror panel at storm condition (not tested yet)