Rigid low cost solar thermal panels

Abstract

A rigid solar thermal panel created from thin flexible materials, including a solar absorber layer of a metal sheet coated with a solar absorbent material having dimples, a tensioned optical film above an upper surface of the solar absorber layer, and an insulation layer. The insulation layer is spaced apart from a lower surface of the solar absorber layer to form a cavity. The dimples project into the cavity and at least one of the dimples is in contact with the insulation layer, thereby providing rigid support for the rigid solar thermal panel.

Description

BACKGROUND[0001]Solar thermal panels capture solar radiation in the form of heat. An absorber, typically a metal plate or foil coated with a specialized solar absorber or black paint, converts incident solar radiation into heat through the process of solar absorption. The absorbed heat can be used in many ways, including to directly heat air in a forced air heating system or water in a forced hot water system, or to evaporate a fluid in an absorption chiller of a refrigeration cycle. The amount of solar energy available for use is described by what is known as the solar constant, which is a measure of unit energy per unit time per unit area of incoming solar electromagnetic radiation. The solar constant is typically represented in kilowatts per square meter (kW / m2), and the average value of the solar constant has been determined to be about 1.361 kW / m2. Accordingly, over the span of an hour, a one square meter solar panel with 100% conversion efficiency would generate approximately ...

AI Technical Summary

Benefits of technology

The present invention is about solar thermal panels made from thin flexible materials that can be lighter, rigid, and highly efficient. The panels have a cavity filled with a metal sheet coated with a solar absorbent material, a tensioned optical film above the metal sheet, and an insulation layer. The metal sheet includes dimples that provide rigid support for the panel. The method of manufacturing the panel involves creating dimples in the metal absorber sheet, placing an optical film on top, and applying a force to secure the optical film to the solar absorber layer. The resulting panel is much lighter than traditional rigid panels, but performs just as well if not better. The technical effect of this invention is that it allows for the creation of efficient, rigid solar panels using flexible materials that are lighter than traditional materials, resulting in cost savings for manufacturing, transportation, and installation.

Problems solved by technology

All solar thermal panels have less than 100% collector efficiency due to energy and power loss and dissipation.

As a result, a large solar thermal panel, particularly with glass glazing, would weigh too much for economical fabrication, shipping, and installation.

Because of weight and size limitations of the rigid glass and frame materials, the largest practical solar thermal panels have generally been less than 32 square feet, and panels of that size have weighed several hundred pounds.

Even with a flexible glazing (e.g., optical film) in place of solar glass, the rigid frame of a typical solar thermal panel is heavy and limited in length, restricting the panel length to just a few feet.

Images