The US Patent and Trademark Office has issued LightManufacturing a patent for a system that uses concentrated solar thermal energy for molding plastic.

The company claimed that the technology allows low-cost manufacturing of large plastic objects like water tanks and boats without the use of fossil fuels.

LightManufacturing founder and CEO Karl von Kries said the company’s technology eliminates the energy costs of roto-molding or vacuum-forming plastic parts, while offering opportunities to simplify and reduce the cost of the molding system.

The company’s Solar Rotational Molding (SRM) systems can be dropped onto unimproved land and these are shipped into 20ft ISO shipping containers.

SRM systems do not require building, a concrete pad or grid energy connection.

"This ease of installation means customers can put inexpensive production capacity in new markets, or put manufacturing close to customers to reduce transport costs", von Kries said.

The patent depicts the use of heliostats (sun-tracking mirrors) to concentrate heat in a plastic molding system.

An array of the company’s ‘H1’ heliostats produce heat for melting the plastic and a photovoltaic array on the roof of the container provides energy to rotate the molds and operate other equipment.

LightManufacturing estimates that the now-patented processes can be deployed on more than 49% of the Earth’s land area.

"SRM systems do not require building, a concrete pad or grid energy connection."

As most of the solar technology firms work on methods for producing electricity, LightManufacturing solely concentrates on applying solar heat to manufacturing processes, the company said.

Von Kries said that enormous opportunities exist to harness solar thermal energy for industrial applications.

"Many processes that burn natural gas or other fossil fuels to generate heat is a candidate for conversion to solar thermal, and the plastic molding processes covered by this patent happen to be two of the best first applications of our technology," von Kries added.

The company’s H1 heliostat delivers more than 2,000W of energy to a target – or over 230,000 lumens for lighting applications.

It also offers the lowest cost-per-reflected watt of any commercially available heliostat and provides easy setupm and optional wireless control, the company said.

Image: LightManufacturing secures patent for solar plastic molding technology. Photo: courtesy of LightManufacturing