A pilot study on the coupling potential for a hydrokinetic turbine within the Amazon basin : - Optimization from an energy perspective

Sammanfattning: Many people around the world still lack access to a reliable electricity grid. Supplying electricity to remote off grid areas like villages around Leticia, Colombia is often interrelated with high costs and geographical limitations. Today most of the electricity demand is met through the usage of diesel generators. The generators are easy to use and have a relatively reliable functionality. However, fuel is expensive and there are other negative aspects as fumes and sound pollution. In order to provide a cleaner, more reliable and cost efficient alternative the company Jabe Energy AB has in cooperation with the volunteer organization Ankarstiftelsen developed a new type of hydrokinetic turbine (slow moving none damming turbine). Previous studies have shown that there is potential for hydrokinetic turbines to increase their power output simply by their relative placement (coupling potential). That is, it might be possible to extrude more power from a system where two hydrokinetic turbines are placed in a close relation rather than being completely separated. Since the turbine investigated is newly developed there have been no previous studies regarding its specific coupling potential. To investigate this potential given the conditions in the Amazon basin, a field study is conducted where measurements on water velocity at different heights in the water column is collected. The data is later used as input conditions for a turbine model developed in the program COMSOL. The aim is to use simulations in order to determine whether a turbine is sensitive for its relative placement to a former (coupling potential) and furthermore to investigate a possible optimal turbine coupling position. The results will show that the turbine is coupling sensitive and that there exists more advantageous placements. Comparing the best and worst case of the coupling study displays an 11.87% difference in possible energy output. The conclusion is that further empirical studies are necessary in order to validate the results. Finally a suggestion on how these studies should be conducted is presented and discussed.