Operational Strategies of Wet Cycle Micro Gas Turbines and Their Economic Evaluation

Abstract

The simultaneous expansion of variable renewables and combined heat and power (CHP) plants in Europe has given rise to a discussion about their compatibility. Due to the concurrence of high wind power generation and high heating loads, it has been argued that only the flexible, electricityoriented operation of CHP plants could go along with the extended penetration of renewables in the European energy system. The current work focuses on the wetcycle simulation of a Turbec T100. Three operational strategies are applied on the heat and electricity demand data of a public building, to assess the economic and environmental performance of the wet cycle. The operation of the micro gas turbine (mGT) is modeled in aspen plus, and the model is validated with data found in the literature. The economic aspects of the operational strategies are assessed with a financial model, which takes into account the current CHP policy incentives and price levels. Furthermore, the advantages and drawbacks of wet operation are highlighted by its comparison to the typical heatdriven operation of drycycle mGTs, with a reference to the same case study. It is shown that the wetcycle turbines have a higher number of full load equivalent operating hours and can achieve higher investment payback, with minor drawbacks to their overall environmental performance.