Report (Part 2): Sustainable Development Convention 2002

SOLO: Solar Desalination

Time: 30 October 2002, 16:00-17:00 Location: Salle B Chair: Werner Kasel, IBEX Presenters/ Participants: Prof. Anne Dimitrov, Geneva Engineers School (EIG)
Yves Meillier, Designer of Project, Skuns Ltd
Antonio Pedro Alvez Lopez, Cape Verde Representative
Werner Kasel, IBEX Investment Group Reporter: Simon Hetherington (ICVolunteers) Languages: English Key words: SOLO, desalination, solar energy, water

An interesting workshop took place outlining in some detail the hopes and aspirations of both the project and its promoters. It led to a wide and lively discussion from the room raising many interesting points concerning such things as cost and manufacturing. The main outcome of the workshop was that the project was very much worthwhile.

The chair Werner Kasel, IBEX, introduced the panelists and asked for one of them to describe the project.

Anne Dimitrov (EIG) using a projector first introduced the Geneva Engineers School and its chemical engineering department where preliminary tests for the desalination units have been conducted. She explained that the project was designed to create autonomous desalination units using solar power, a powerful process of about 45Kw solar energy collectors to produce a quantity of up to 5,000 liters per day of purified water from brackish, brine or salt water. She pointed out that 1.1 billion people still have limited access to improved water supply and that the project has far reaching implications throughout the globe. She went on to describe how the process of desalination works. Previous desalination techniques have used such methods as distillation, reverse osmosis, freezing, ion exchange and solvent extraction to change undrinkable water into drinkable water. In 2002 a new system of desalination was created and a prototype was built that could produce 1.2 liters of drinking water per hour. The aim of the project is to develop a better prototype that could produce 5000 liters of drinking water per day from real sources of salty water.

Yves Meillier, Skuns Ltd, explained in more detail how the solar panels would work and how the membranes that desalinate the water would work. He pointed out the desalination units would be mainly confined to tropical seaside and dessert areas due to the need for high sunshine levels and that the conditions of the location could have dramatic affects on the performance of the unit. Such things as sand and dust are very bad for the membrane and the unit works better in humid climates. The units themselves are relatively simple to operate with 2 fans and pumps and thus need little technical knowledge to operate them. This in turn makes them relatively inexpensive at only ,000 per unit producing water at .6 per cubic meter. He went on to talk about a personal survey he had conducted, which suggested that there was a very high demand for this technology especially from hospitals, hotels and small remote villages. Mr. Meillier ended by explaining a little about the desalination project being set up in Cape Verde, which was set up there because of its similar size of population to Geneva and because of the climate.

Surprising Issues

• The cost of membrane (up to 85% of costs)
• If the new type of membrane is produced many others will become obsolete leading to companies being reluctant to produce them.
• A problem with manufacturing anywhere else but Switzerland. It appears that the membranes have to be manufactured with Swiss precision.

Interesting Questions

Q. What filters do you use?
A. Dynamic filters unlike any preceding ones, possibly similar to a centrifuge.

Q. Can it be used for irrigation purposes?
A. No, it would be extremely expensive, as the economies of scale do not apply to this technology.

Conclusions
The project has far reaching potential in many parts of the world, and as Werner Kasel proposed at the end of the workshop 'the 21st Century is a Century of water and no one is willing to share'. If successful this project will empower many people providing them with cheap drinkable water, although, there are still many hurdles to overcome.