UC Irvine

The residential sector is responsible for 20% percent of total U.S. emissions. Emissions from the residential sectors can largely be traced to energy use in buildings. The demand for energy has been on a steady rise despite limited accessibility of non-renewable resources. Solid oxide fuel cells (SOFC) comprise an alternative technology which has high fuel to electricity efficiency, and can be powered by renewably sourced fuels. In this study, the waste heat from the fuel cell is captured and processed either through an Organic Rankine Cycle (ORC) to provide extra power or absorption chiller (AC) to provide cooling for meeting the power and cooling demand of a residence or community. A spatially resolved dynamic model was developed in Matlab/Simulink to study dynamic characteristics of an SOFC system based on a previous model developed at the National Fuel Cell Research Center. A dynamic model was developed for the ORC and AC in Matlab/Simulink to study the dynamic characteristics of the combined system. This model was then used to evaluate the performance of the system in terms of efficiency, capacity, and dispatchability, based upon measured load profiles of residential buildings. Dynamic data from a residential complex were used as an input to evaluate the dynamic system model. The SOFC was capable of following the highly dynamic load with an average electrical efficiency of 46%. Seven present more power was produced through the ORC cycle with 10 % efficiency. The AC generated an average 125 kW of cooling with an average COP of 1.08.