More efficient and cheaper solar panels developed

Milnes Family introduced new materials to an already existing technology.


The construction engineer Osvaldo Milnes had almost twenty years of experience with heating systems at the beginning of the decade when by pure coincidence an idea that was to revolutionize his life appeared before his eyes. While working on a drip irrigation system, he discovered the high temperatures that the water absorbed while circulating through certain plastic tubes.

Not too long went by before he had produced what is now the star product of the company Calder Solar: an efficient panel made with cheaper and more resistant materials that have very low maintenance costs compared to conventional systems and a lifespan of 20 years.

The formula was based on replacing key materials. The top was replaced with a double layer of polycarbonate to favor the greenhouse effect inside the box, while the eight meters of copper piping were replaced with 40 meters of polypropylene, which prevented freezing and the subsequent destruction of the device, which has a 20-year lifespan.

“These synthetic materials allow the system to be connected directly to the drinking water grid, which prevents heat loss – calculated as up to 50% in traditional panels – and temperatures of up to 60º C (140º F), considering that both personal hygiene as well as washing dishes only requires around 38º C (100º F),” says Tomás Milnes, a professional architect who works with his father in the Calder Solar company.

For a typical house that requires around 50 liters (13.2 gallons) of hot water for each of its members per day, the Milnes’s system promises an installation cost of up to 40% less (calculated at US$ 1,400), monthly savings of around US$ 40 in gas, and a return on your investment in two years.

Fantastic projections

Calder Solar’s adventure has earned it prizes, the latest of which was the Avonni Prize for energy, awarded by the nonprofit Chilean institution Foro Innovación together with the communications media, government agencies, and private companies.

For Tomás Milnes, this acknowledgement has been the culmination of “my father’s trajectory and an eight-year process that has concluded with an optimal product.” In addition, he affirms that “it comes at precisely the right time,” as President Michelle Bachelet recently ratified a law to promote clean energy.

The law, which could be materialized by the end of the year, when the technical requirements are determined, considers tax breaks that cover the full cost of installing panels in new homes worth up to US$ 75,000 and a minimum of 20% in properties of up to US$ 170,000.

Anticipating this almost certain increase in demand, Calder Solar has entered into a partnership with THC Chile, which will provide the water distribution systems and will undertake the mass production of its star product, which will be called Ecopanel.

Parallel to the eventual operations with domestic real estate developers, the company will continue to serve the 100 customers between Antofagasta and Chillan – along almost 1,800 km (1,100 miles) of Chilean territory from north to south – to satisfy their need for hot water in bathrooms, kitchens, and swimming pools with a proven technology that could also be implemented in other countries in the medium term.