A polygeneration system is an energy system capable of providing multiple
utility outputs to meet local demands by application of process integration.
This paper addresses the problem of pinpointing the optimal polygeneration
energy supply system for the local energy demands of a livestock farm in
terms of optimal system configuration and optimal system capacity. The
optimization problem is presented and solved for a case study of a pig farm
in the paper. Energy demands of the farm, as well as the super-structure of
the polygeneration system were modelled using TRNSYS software. Based on the
locally available resources, the following polygeneration modules were chosen
for the case study analysis: a biogas fired internal combustion engine
co-generation module, a gas boiler, a chiller, a ground water source heat
pump, solar thermal collectors, photovoltaic collectors, and heat and cold
storage. Capacities of the polygeneration modules were used as optimization
variables for the TRNSYS-GenOpt optimization, whereas net present value,
system primary energy consumption, and CO2 emissions were used as goal
functions for optimization. A hybrid system composed of biogas fired internal
combustion engine based co-generation system, adsorption chiller solar
thermal and photovoltaic collectors, and heat storage is found to be the best
option. Optimal heating capacity of the biogas co-generation and adsorption
units was found equal to the design loads, whereas the optimal surface of the
solar thermal array is equal to the south office roof area, and the optimal
surface of the PV array corresponds to the south facing animal housing
building rooftop area.
The Working Principle of a Turbine “Case Study: GE Frame 9E Gas Turbine”