6 research outputs found
Inflatable plastic solar still with passive condenser for single family use
Plastics have been the preferred choice of material for the commercial production of the solar stills. However, most of the currently available solar stills are either too big or too small for satisfying drinking water needs of a single family. Furthermore, methods for increasing the production of water from a solar still are often difficult and costly to integrate in a solar still. Here, we show the effect of adding a plastic channels as passive condenser on an inflatable solar still. The still has a basin area of 1.8 m2. The tests were performed in lab conditions at different water temperatures. The production of water achieved from the still at a water temperature of 73 ° C was 0.75  l/h. Furthermore, the production of water increased to more than 0.95  l/h with use of air flow over the the passive condenser to mimic wind or with use of wet tissue on the passive condenser to mimic evaporation cooling.Accepted Author ManuscriptChemE/Transport Phenomen
Electrocatalysis for the Hydrogen Economy
This chapter deals with the concept of “hydrogen economy”, which was introduced by John O.M’ Bockris in 1972. We summarize the fundamental principles and the progress for the reactions relevant to the hydrogen economy, namely the hydrogen and oxygen evolution for water electrolyzers, and the hydrogen oxidation and oxygen reduction for fuel cells. The activity of each reaction can be correlated to a single descriptor, i.e. the adsorption energy of a key reaction intermediate, following a volcano-type relationship. Highly active materials can be prepared with the aid of modern computational and experimental tools. Nevertheless, to develop catalysts that are substantially more active and reach the performance of ideal catalysts, the focus must be placed on materials that can break the energetic scaling relations between intermediates. The systems of choice are acidic water electrolyzers or fuel cells, using noble metals for the catalytic material, despite the great progress made in the field of alkaline systems. However, to realize the concept of hydrogen economy on a large scale, the electrode material for either reaction must combine activity, stability and abundance