Sustainable energy through multigeneration systems

Multigeneration (e.g. cogeneration and trigeneration) systems simultaneously produce power and useful heating/cooling effects. They have the advantage of very high efficiency of primary fuel utilization, and offer opportunities for significant reduction in carbon emissions compared to the single generation (i.e. power only) mode. This paper focuses on the evaluation of overall performance of multigeneration systems using different prime movers for a comparative assessment. An 'Electrical Equivalent Efficiency' of a multigeneration plant has been proposed. Such an overall efficiency has been evaluated for three major prime movers i.e. diesel/gas engine, gas turbine and steam turbine in the multigeneration mode. An integrated system for production of fresh water, cooling and power (for tropical coastal areas) has also been proposed and analysed. In all cases, it was observed that there is a significant improvement in primary fuel utilization efficiency (as high as 19%), leading to a significant potential (as high as 50%) for reducing carbon emissions. © Common Ground, Ravi Prakash, Alex Henham, All Rights Reserved.