Investigating the Development of a Smart Home Community Heated and Cooled by a Centralized Geo-Exchange System

Abstract

As the world tackles increasing complications from climate change, scientists and engineers continue to find new ways to reduce our carbon footprint. Heating, cooling, and powering residences accounts for 20% of greenhouse gas emissions in the United States [1] — we are interested in assessing ways to reduce energy consumption in the residential sector. The core of our project prioritizes designing an energy-efficient home using passive design techniques and smart home features to minimize energy requirements, ultimately decreasing the overall carbon footprint of the home. We examine the scaling and integration of this thermally efficient home in a community environment with an optimized central energy source. To heat and cool these homes, we investigate the potential to incorporate a community- scale, open-loop geo-exchange system that utilizes ground source heat pump technology. Geo-exchange systems are the most energy-efficient HVAC systems available, however due to sizable land requirements and high upfront capital costs, they are often not cost-efficient on an individual residential level. At the community-scale, however, incorporating a shared- loop geothermal system allows for cost savings through factors such as increasing economies of scale, load diversity, and load aggregation. This thesis proposes a straw-man design for a community of energy-efficient smart homes based in the Boston area in Massachusetts, centralized around a community-scale, open-loop geo-exchange system. Examining the heating and cooling loads associated with different designs allowed us to iterate through the design process and obtain an optimized design. Global optimization is not trivial, and like in the case of this project, it can depend on a vast number of variables that are difficult to control. Rather than investigating a global optimum, we explore several local optima within what we believe are the most important areas of the home and the community. Even without a globally optimized final design, we can demonstrate the great potential for energy and cost savings within sustainable communities. There is also some mid- to low-level focus on particular aesthetic features of the home that would integrate efficiently with the energy source, along with overall homeowner satisfaction. We seek to lay the groundwork for the strategic planning of future sustainable communities.