Coupling of a Solid Oxide Fuel Cell Auxiliary Power Unit with a Vapour Absorption Refrigeration System for Refrigerated Truck Application

Abstract

Modeling studies have been carried out to investigate coupling of an solid oxide fuel cell auxiliary power unit (SOFC APU) with a small scale NH3–H2O based vapour absorption refrigeration system (VARS) for a refrigerated truck/trailer application, by using hot cathode exhaust from the SOFC stack to drive the VARS. A bottom up design and modeling approach has been adopted where the end requirements, cooling load in this case, are identified first followed by upstream modeling of the SOFC and VARS unit. This approach enables design of system/components to meet the desired end requirements rather than compromise or fall short of the desired goal.Initial modeling results show that it is indeed possible to couple an SOFC with a VARS on a small scale (< 10 kW cooling load) for the refrigerated truck application. As this novel strategy utilizes both heat and power from the SOFC it promises a higher total efficiency up to 80% and also removes a significant part of the load from the main diesel engine, thereby leaving the engine to carry out the task of only propelling the vehicle. The excess electrical power from the SOFC could also be used to charge the vehicle batteries.

Comparative study of solid oxide fuel cell coupled absorption refrigeration system for green and sustainable refrigerated transportation

“…It was found that the system depicted maximum COP of 0.45 at 154C desorber temperature. However, the results from the energy analysis of the VARS will not be presented here as there are plenty of studies available ( [18], [24], [37], [38]) of the thermodynamic analysis of NH 3 -H 2 O VARS.…”

“…The required refrigeration load inside the refrigerated space needed to be calculated accurately as the system size and its characteristics depend upon the load. The method developed by Venkataraman et al [18] was employed to calculate the thermal load of the refrigerated truck. The refrigeration load of a large refrigerated trailer (40 ton gross weight), medium refrigerated truck (12 ton gross weight) and small refrigerated van (1 ton gross weight) were taken from the work presented by Venkataraman et al [18] for the further calculation of the SOFC stack…”

“…Venkataraman et al [18] carried out simulation for an SOFC-coupled NH 3 -H 2 O VARS for refrigerated truck transportation. The initial results suggested that the designed system promised an efficiency of combined heat and power of 80% and that the SOFC could remove a considerably amount of load from the engine.…”

The Exergy Costs of Electrical Power, Cooling, and Waste Heat from a Hybrid System Based on a Solid Oxide Fuel Cell and an Absorption Refrigeration System

“…However, the authors did not report any productive structure, nor do they make a difference between product and residues costs. However, the idea of coupling a VAR system to a SOFC had already been previously reported by Venkataraman et al [11], in which they provide only a detailed thermodynamic analysis of the hybrid system for truck applications. Torres et al [12] presented the fundamentals of the methodology for determining exergy cost through the theory of the exergy costs, but they did not apply it to a system such as the one presented in this work.…”

Design and Optimization of a Fuel‐ and Air‐Preheater for Reversible Solid Oxide Fuel Cells

“…Waste heat recovery has been used in many aspects , . The exhaust heat from RSOFC is often used for heat exchanger or cabin heating . If exhaust heat from SOFC stacks is not used, it means that half the available useful fuel energy is wasted .…”