4637 -- A Parametric Analysis of a Grid-Independent BCHP System—Focusing on Impact of Technological Advancements

Taking full advantage of technological advancements for design and construction of building cooling, heating, and power (BCHP) systems necessitates prioritization of the system components for optimum allocation of the available resources. Adopting this approach for a given application requires an assessment of how the efficiencies of the constituent components affect the overall BCHP performance. This paper will demonstrate the importance of such an assessment through a parametric analysis for a hypothetical BCHP system integrated with an office building in Atlanta. The selected BCHP system consists of gas-fired microturbines for on-site power generation, thermally activated systems for cooling and heating, and electrical equipment for lighting and other functions. The components encompassed by this parametric analysis are the microturbines/gas turbines, thermally activated absorption cooling system, and building electrical equipment. The BCHP system, along with auxiliary gas-fired burners, meets the electrical and thermal loads of the building without any interaction with the electric utility grid. The parametric analysis involved perturbation of the performance indices of the system components and evaluation of the corresponding effects on the total energy consumption through a nondimensional approach. This study revealed that, for the office application under consideration, (1) a significant improvement can be expected by using more efficient on-site power generators; (2) use of recuperated microturbines is more advantageous from the standpoint of primary energy consumption; (3) incorporating an efficient single-stage absorption cooling technology is quite sufficient, although use of more advanced absorption systems becomes attractive at higher power generation efficiencies; and (4) the significance of promoting efficient use of electrical equipment through effective building energy management should not be overlooked, even in the context of BCHP.

Units: SI