Assessing Emission Reduction Potential of Small-Scale (>100 kWe) Combined Heat and Power Systems for Multi-Family Residential Buildings in the United States

The objective of this paper is to investigate the emission reduction potential of residential small-scale (>100 kWe) combined heat and power (CHP) applications in the United States. The US has a relatively low number of residential CHP installations compared to other countries, and no existing literature investigates the emission reduction potential of small-scale systems while also accounting for climate zones across the United States. Existing emissions analyses exist for larger, industrial applications across multiple technologies and designs, but none exist for small-scale systems. To address this gap, we assess how the emissions impact of a small-scale, natural gas CHP system compares with the local electrical grid in five climate zones across the United States both with and without thermal energy storage (TES). This is accomplished using an in-house program in Python coupled to EnergyPlus that is used to size the CHP and/or TES systems according to the thermal demand profile, optimizes CHP and TES energy dispatch throughout the year to meet demands, assesses the system s economic feasibility, and calculates the carbon emission reduction or increase relative to the local electrical grid. The Python program will be open-source and designed for use by both researchers and building owners who are considering CHP. The findings will be useful for policymakers and end-users interested in leveraging the high efficiency of small-scale CHP systems in residential applications.