Details on technical concept and requirements The technical concept The WaterPyramid is a uniquely designed foil structure, utilizing energy from the sun to evaporate dirty or polluted source water and to condense high quality drinking water. The concept is primarily based on the solar still principle, but the WaterPyramid is the first, stable application optimized for large ground areas. Being able to cover these large areas, allows the capturing of large amounts of sun-energy and subsequently the production of substantial amounts of drinking water. The WaterPyramid can provide communities of hundreds of inhabitants with enough drinking water to fulfill the basic water needs. Hybrid system: solar distillation and rainwater harvesting Apart from the solar driven type of water production, the WaterPyramid is a hybrid system in that it can also be used for rainwater harvesting if the climate conditions are such that a rainy season occurs. The harvested rain water is gathered in a large water tank and purified (using filtering and silver disinfection techniques) for drinking water purposes. Various types of water are produced In operating the WaterPyramid, various types of water are produced such as: 1. Drinking water, for direct and local consumption; 2. Bottled water, to market; 3. Distilled water for industry-, veterinary and medical use 4. Water used for washing and cooking; 5. Water for agricultural applications. Easy to maintain, durable and flexible The WaterPyramid is simple to install, to operate and to maintain. It can be operated by a locally recruited labor force. The technology used is sustainable and the materials used reflect the high quality of the design. The WaterPyramid is designed using a modular concept leaving space for future expansion on demand. As source water clients have the flexibility to use salt water, brackish water or polluted river water. Appropriate Technology Appropriate Technology (AT) forms the backbone of the WaterPyramid: The concept is environmentally friendly due to a very low energy consumption (the desalination process is solely driven by sun energy) and minimal production of air pollution and brine. The WaterPyramid can be maintained by a locally recruited workforce and offers local communities the ability to increase their income. Last but not least, due to the low operational cost, the WaterPyramid can easily compete with other desalination technologies. Technical Details WaterPyramid with a total area of 600 m and situated under favorable tropical conditions, can produce up to 1.250 liters of fresh water a day. The production rate is dependant on site specific situations factors such as climate and temperature, cloudiness and wind activity. Desalination is driven by the sun and the energy needed for pressuring the WaterPyramid is obtained using solar cells in combination with a battery back-up system. Intermittent peak demands in electricity, related to e.g. (borehole) pumping and maintenance, are covered using a small generator system.