Abstract:
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Reducing dependence on fossil fuels is the need of the hour as climate change threatens to disrupt the world’s ecosystems. Nowhere are these effects more apparent than in small oceanic coral atolls. Balancing the energy needs of urbanising populations with the fragility of these systems is a challenge. This thesis examines the current energy model of two Indian Ocean islands in the Lakshadweep Archipelago (Minicoy and Kadmat), and proposes two new energy models which include renewable energy systems that may partially replace diesel, become economically profitable and do the least damage to fragile marine ecosystems. The current energy model and characteristics of both islands were studied and restricted all potential interventions from areas within reef lagoons which contain potentially vulnerable ecosystems like lagoonal patch reefs, seagrass meadows and reef crests. These habitat maps are notional, and not based on ground-truthed data. However, it serves as a heuristic approach to exploring alternate energy systems in atolls like Lakshadweep. The simulation programme HOMER was used to explore different available hybrid energy systems and to evaluate their technical and economic performance. The simulation analysed, combined and compared the feasibility of using several alternate systems consisting of floating PV panels, windturbines and diesel generators (which are currently the primary source of energy on the islands). Several hybrid models were obtained which were analysed with the statistical software Minitab to identify an optimal hybrid model. For Minicoy, a hybrid system with 300 kW of floating PV panels, 7 wind turbines and 600 batteries (15 string of 40 batteries each, connected in parallel with a voltage for each string of 480V) to supplement existing diesel generators was determined as the optimal system achieving 21% of renewable energy production. For Kadmat, a hybrid system with 800 kW of floating PV panels, 1 wind turbines and 1200 batteries supplementing existing diesel generators was identified as the ideal combination achieving 28% of renewable energy production. It must be emphasized that these models need to be evaluated against ground-truthed habitat maps of the lagoon. These heuristic models would reduce diesel consumption in a 16% for Minicoy and a 29% for Kadmat; and would also reduce the total cost for both islands, 8% for Minicoy and 12% for Kadmat, with a low initial investment of 2.4 million dollars for each island. Despite these models would have a low impact in the local ecosystems, they would affect them. So, in the final analysis, this project raises larger questions of how best to mitigate the global effects of climate change, when these measures may impact local ecosystems, that are already succumbing to a changing climate. For atolls like Lakshadweep, we must be careful that the cure does not turn out to be worse than the disease. |