The Suncone Solar Power Generator

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PROJECT NARRATIVE

1. State-of-the-Art

 Focusing solar energy to high intensity can provide high temperatures at the target (focal point) in order to drive high-efficiency heat engines for the production of electricity or for other purposes. Parabolic trough reflectors have been used effectively in this role. Parabolic dish mirrors can achieve higher temperatures and higher efficiencies.

The problem with parabolic dish mirrors is that considerable precision is required in their construction and maintenance. The mirror facets are fairly expensive to manufacture. Each facet must be mounted on a very rigid structure and must be precisely aligned to keep the sun's image on the target. About once a week, each mirror must be re-aligned. Another problem with parabolic dish reflectors is that they have been known to start fires in grass when accidentally pointed in the wrong direction. They can also cause damage to human eyes if the mirror points in a direction that causes sunlight reflection toward a person or if the person looks at the target (focal point).

A new system called “Suncone” provides an inexpensive method of producing high-temperature solar energy collection using plastic films. Figure 1 in the Appendix shows an artist's conception of the Suncone solar collector. Like the parabolic dish, it must be pointed toward the sun but requires less precision than a parabolic dish or parabolic trough. Air pressure within the enclosure and diagonal interior wires maintain the rigid configuration.

Table 1: Efficiency Comparisons of Various Solar Technologies

The table above compares Suncone with other types of solar electric power generator systems. The solar collection efficiency of the CSP devices depends on the temperature of the target. The CSP devices in the table were calculated at comparable temperatures. The CSP devices in the table were calculated at comparable temperatures. The comparison is not totally fair to photovoltaic systems, because the concentrator systems require turbines and generators. Even so, photovoltaics produce power at a higher cost per kilowatt-hour.

U.S. Patent 4,267,824 (2) describes an inflatable solar concentrator that consists of a flexible material inflated to the shape of a cone with a transparent end covering. Internal air pressure maintains the shape. The problem with this design is that the entire cone is supported by its narrow end. Thus, wind could easily blow the cone to the side. If guy wires are used, they tend to crumple the narrow part of the cone. Other concentrating cone designs have been patented, but none of them incorporate the unique features of Suncone that make it inexpensive and robust.

Introduction | Part 1 | Part 2 | Part 3 | Part 4 | References