What could be fresher? On his way home from the office, the computer scientist harvests tomatoes from his company's rooftop greenhouse. The plants growing there thrive on the building's purified waste water and waste heat. Plantation systems such as this are still unheard-of in Germany. But they may make their debut soon: "In our inFarming project which is short for 'integrated farming' we are developing solutions that can be speedily implemented for the urban landscape. Our goal is to grow vegetables atop existing buildings," certified engineer Volkmar Keuter, project manager at the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT in Oberhausen, explains. Actually, there are many varieties of plants suitable for growing on city farms. "Along with vegetables and fruit, we also want to look into growing plants that produce active ingredients for medications."
The benefits: reducing the area required for agriculture, almost no transportation costs and, as a result, lower emissions - not to mention the boost in freshness when the tomatoes grow right on the consumer's roof. Waste heat from buildings and additional solar modules would be enough to supply the greenhouses with the energy they need. Semi-transparent solar cells are ideally suited for the purpose because they do not rob the plants of the light they need to grow. Water consumption is minimal, too: in a self-contained system, water used for the plants is circulated back, cleaned and reused. Multifunctional microsieves and photocatalytic and thus self-cleaning coatings keep the water quality high. Nutrients for the plants can even be filtered out of rainwater and waste water. "Our concept relies on hydroponic systems or hydrocultures. A thin, controlled film of water is all it takes for plants to absorb needed nutrients. The advantage: the yield is ten times higher, and soil is too heavy for many building roofs. That is why we are working on systems to supply plan
|Contact: Volkmar Keuter |