Sustainable Energy Source for Water Pumping at Puttalam Salt Limited
The cost of grid based electrical and diesel sea water pumping to salt fields is one of the major cost components out of the total production cost in Puttalam Salt Limited, situated in northern part of Sri Lanka. In order to explore ways and means to improve the energy efficiency and alternative resources to meet the energy requirement a feasibility study was conducted using power system simulation software, (HOMER) and also detailed technical, environmental and financial tools. This research study is conducted to evaluate the performances and applicability and propose the most suitable sustainable renewable energy source and methodology for water pumping to salt fields instead of currently utilized grid based and fossil fueled energy supply. Preliminary results obtained by simulation software shows that direct wind mill pumping and solar PV water pumping was found to be unfeasible due to its limited pumping capacity and high investment cost. More over solar PV does not seems much feasible due to its high cost of energy (0.234 US $/kWh) compared to wind powered rivals in this type of applications. Based on comparisons of the analysis it is seen that the wind/ grid combined configuration of 04 units of AOC15/50 model (50kW manufactured by AOC Renewable Energy – Canada) wind turbine units with 150kw inverter seems to be a logical supplement for water pumping energy requirement than using grid based electricity which costs 0.201 US $/ kWh. The solution in this research affords an attractive 60% annual average renewable fraction as well as an approximate 215.8 tCO2(eq) of annual Carbon Footprint saving. Also it assures a moderate Discounted Payback Period of 6 years and 5months with a 15% of Internal Rate of Return.