Solar energy for power, heat and water: Airlight's Sunflower

The Sunflower is a versatile solar energy "harvester" by Swiss company Airlight Energy. It provides power, heat and water, and can be transported in a shipping container.

I love ingenious solutions to environmental problems, and this is one of the most interesting ones I've seen in years. I came across it in a New Scientist article by Paul Marks published in the 4 October 2014 issue, and available online as Sunflower solar harvester provides power and water. Below is what it looks like.

As it fits inside a single container, transport is relatively easy to any location. The dish is ten metres high and tracks the sun. Besides clean water and electricity, it can even provide refrigeration if a heat pump is used.

The article explains that the technology for the water-cooled solar panel was developed by Bruno Michels and colleagues at IBM, and Airlight have licensed the patents. I have noticed several possibly relevant World applications by Michels at the Swiss base of IBM, listed here.

Photovoltaic module cooling devices is obviously relevant, and is illustrated below.

The article explains that each panel holds 25 photovoltaic chips cooled by water flowing in microchannels. The cooling effect means that the panels operate at their optimal temperature, so a quarter of the panels are used to produce the same power as conventional panels.

The heated water can then drive a low-temperature desalinator in coastal areas, going through three cycles, producing 2500 litres of fresh water daily. Away from the coast a water purifier can be fitted. A relevant IBM patent document, Desalination system and method for desalination, is illustrated below.

The dish itself consists of numerous 1-metre mirrors, which direct the sunlight onto six panels which produce the panel. Normally the mirrors would be heavy, polished glass, but instead they are made of metallised foil, like chocolate bar wrappers.

Tests on an 18-mirror prototype showed a 30% efficency rate and a 50% heat efficiency rate. A 36-mirror version should be able to provide 12 KW of electricity and 20 KW of heat from 10 hours of sunlight.

I have found 18 World patent documents by Airlight which are on solar energy.

Tests are to be carried out in seven sites, probably in Morocco and India, with sales beginning in 2017. As might be expected, the entire design is meant to be low maintenance.