Prediction of emission intensity for 1 MW onshore H-OTEC in Malaysia

抄録

Ocean Thermal Energy Conversion (OTEC) is a potential green renewable energy source, especially for tropical coastal areas. The system utilizes the temperature difference between surface and deep seawater to convert into electrical energy. The system is referred to as Hybrid-OTEC (H-OTEC) when coupled with seawater desalination. This paper investigated the emission intensity of a 1 MW H-OTEC proposed in Malaysia via Life Cycle Assessment. The inventory data for the working cycle and structure is obtained by scaling up the 3 kW H-OTEC pilot plant in Malaysia. Two upscaling methods were investigated, namely the conventional 0.6 rule and the newly proposed “Thermodynamics scaling method”. The 1 MW H-OTEC is shown to associate with 71.5 g CO2-eq/kWh of emission intensity, 85% lower than the small-scale pilot plant and becomes comparable to mainstream renewable energies. In addition, the Thermodynamics scaling method is more reliable for H-OTEC upscaling, otherwise would result in about a 25% underestimation in emission intensity prediction. Further upscaling of H-OTEC will bring its emission intensity to a more competitive level with the other large-scale mainstream renewable energies, making it a more favourable choice for Malaysia’s future renewable energy mix.