An energy, exergy and economic modeling study based on utilizing waste heat energy of a C200 microturbine to power ORC, absorption chiller and desalination units
PhD ThesisThe motivation for this investigation into microturbine and desalination processes is the desire to combat problems caused by frequent high temperature conditions related to the spread of global warming. The small-scale power microturbine C200, designed by the Capstone Co., was chosen. Also, a single effect absorption chiller was employed in this study. The method of thermal vapor compression multi-effect distillation desalination was chosen as a potable water producer. Also, the organic Rankine cycle was powered by low-grade heat energy. Each model was simulated and investigated on a stand-alone basis under ISO conditions using off-design simulations. The ORC, absorption chiller and TVC-MED desalination process were separately driven with the same amount of fuel consumption into microturbine. All the base and proposed models were simulated by using a software package called IPSEpro. The economic accessibility and profitability of all the proposed models was examined.
Integrating the microturbine with the ORC unit led to the generation of an extra 4.10% of electric power compared to that produced by the absorption chiller, and 7.80% for TVC-MED desalination. However, the lowest carbon emission rate for all models was achieved by using a microturbine with TVC-MED desalination with a reduction of 46.80%. Accordingly, the EUF of the TVC-MED desalination was 9.20% higher than when an absorption chiller was used, and 42.40% higher than when ORC was used. ORC gained the lowest EUF. The higher rate of exergetic efficiency was found when utilising the microturbine with the single effect absorption chiller with a value of 31.00%, as compared to ORC and TVC-MED, which registered rates of 23.11%, and 22.42% respectively.
The results of economic study showed that, if the selling price was £0.023/kWh, then the profitability evaluation results would not be attractive for investment. However, if investment was made into a microturbine, then the electricity price could be set at £0.040/kWh or £0.060/kWh, resulting in a desirable economic feasibility for all combined models