The need to change the common place and inefficient methods of power generation, distribution and utilization in the power industry have risen with science and technological development, public policy changes, rise in the cost of energy, global warming and environmental pollution issues. Distributed energy power generation (DPEG) offers solutions to many of the current issues with centralized power generation which makes it a worthwhile alternative. By shifting generation location to homes or districts the power user has control independence, transmission losses are eliminated, and greenhouse emissions can be significantly reduced. This research focuses on setting up and optimizing a numerical model of building powered by a district natural gas-powered internal combustion engine direct current (DC) generator (Power Aire 65) designed for tri-generation or combined cooling heating and power (CCHP). Renewable energy is also incorporated and prioritized for greater fuel savings. TRNSYS Simulation Studio is the primary modelling software. Components of the system were linked like it would be in real life and the energy simulation was run. A typical building with conventional floor plans in the Birmingham metropolis was selected for study and a 3D replica was made using SKETCHUP and imported into the TRNSYS environment for further modification and analysis. A critical objective of this research is obtaining a model that generates reasonable and repeatable results that would accurately and completely describe how energy is generated and used in the building with respect to DPEG, CCHP and all allied systems. Optimization and sizing of the system is also critical as the targeted energy utilization factor is 95%. Overall, this research seeks to make available considerable and convincing data that would advance the integration of DPEG and CCHP into the conventional power industry.