Artificial desert provides answers about solar energy in extreme environments

2020-06-17

[ingress]In a transparent tent deep down in the factory premises of Absolicon, fans hum and visibility is poor. In the center one can imagine the company’s solar collector T160. 27 kg of sand from Chile has been imported to create an artificial desert and tearing sandstorms, with the goal of investigating the performance of solar collectors in extreme environments.[/ingress]

Absolicon has for twenty years carried out research on solar energy and the possibilities to absorb and convert solar radiation into process heat for industries and district heating.

The result is the company’s latest solar collector Absolicon T160 which delivers heat up to 160 degrees to customers around the world. The Absolicon T160 has been tested at the Swiss Institut für Solartechnik (SPF) in Rapperswil and achieved the highest optical efficiency to date for a small commercial trough and was the first of its kind to be certified according to Solar Keymark,the European standard for performance and quality.

“We know that our solar collector is one of the best of its kind and performs above normal levels in what can be described as a normal environment. Now we want to find out more about how the solar collector works in extreme conditions, explains Jonatan Mossegård, technical manager at Absolicon.

Absolicon’s T160 has a patented trackingsystem that allows the solar collector to follow the movement of the sun during the day. Thanks to its rotating position, the hypothesis of the project is that the Absolicon T160 can easier self-clean itself in dusty environments compared to flat solar panels or fixed solar collectors.

“We feel relatively confident that the rotation brings several clear advantages,” explains Jonatan Mossegård.

One advantage is that some dust and sand simply fall off the solar collector during the day as it rotates to follow the sun. Another is that the T160 turns the receiver glass to the ground during the night. This reduces the condensation on the surface and the risk of dust reacting with the moisture and forming a permanent coating, called cementation.

Perform tests in the Atacama Desert

Absolicon made the decision to let Elias Forsgren test the hypothesis within the framework of his master’s thesis at Umeå University.

The choice of extreme environment fell on the Atacama Desert in Chile. The reasons to investigate this particular place are several.

“The Atacama Desert is one of the most sun-irradiated places in the world. At the same time, it is one of the driest places you can imagine with almost no rain throughout the year,” explains Elias Forsgren.

Solar radiation makes the site extremely suitable for the use of solar energy, but the lack of rain creates challenges as the self-cleaning function of the solar collectors depends on rainwater.

“We know that other installations have encountered problems with the contamination of dust and sand. The dirt reduces transmission and also increases the risk of cementation” , says Elias Forsgren.

Mining industry in Chile interesting

Back to the plastic tent in Absolicon’s premises. The tests with desert sand are examined in two stages, on two continents. Elias has constructed a test station ready to be shipped to the Atacama Desert in Chile to collect data on site. The results are then compiled with observations from the artificial desert created in the tent of Absolicon to draw definitive conclusions about the performance of solar collectors in the extreme environment.

Absolicon currently has seven active framework agreements for the production of solar collectors in South Africa, Kenya, Cyprus, Mongolia, Ecuador, India and Peru. Pilot installations are also planned together with AB Inbev, the world’s largest producer in the brewing industry, and Saline Water, the world leader in desalination of seawater to address water scarcity in areas threatened by drought.

It is hoped that in the near future they will also be able to offer Absolicon’s sustainable energy solutions to industries in areas such as the Atacama Desert. Chile, including its mining industry in the region, is of interest to Absolicon.

“We know that the solar conditions are perfect, and believe that ongoing projects will prove that the environmental challenges are manageable and that our solar collectorse are performing well despite the conditions,” says Jonatan Mossegård.

The project is part of SIKT – a three-year project run by the High Coast Industry Group. SIKT is financed by the European Regional Development Fund, Region Västernorrland, Härnösand, Kramfors and Sollefteå municipality and participating companies.