Techno-economic and environmental feasibility study of non-cloud based Smart Dual Fuel Switching System (SDFSS) for hybrid space heating in cold climates

This paper describes the development and feasibility study of a consumer-friendly, non-cloud based Smart Dual Fuel Switching System (SDFSS) for hybrid space heating, for the simultaneous reduction of energy costs and greenhouse gas (GHG) emissions. A dual-fuel heating system comprises an HVAC system with two thermal energy sources such as an air source heat pump (ASHP) and a natural gas furnace (NGF).

Real time determination of the optimal switching temperature requires knowledge of the building thermal energy demand as a function of outdoor temperature, energy prices, and equipment capacity and performance. Cloud-based variations of Smart Dual-Fuel Switching Systems (SDFSS) require expensive sensors and real-time cloud computing to achieve this, resulting in high implementation costs. Non-cloud based SDFSS can produce comparable results using Internet-of-Things (IoT) technology and building energy models and is implemented at lower cost through a program run on a Raspberry Pi to supply updated variables to the home’s smart thermostat.

Using OpenStudio simulations to approximate the hourly thermal demand of house archetypes, potentials of SDFSS can be investigated in different regions of the province of Ontario, Canada. The viability of using simulations in the place of experimental data is tested by determining the heating demand profiles of various test sites through practical tests conducted during the heating season. Preliminary numerical analysis will be performed to predict resultant energy cost and emissions savings for each test site, followed by experimental testing to validate input parameters and results. Sensitivity analysis will be completed to assess the feasibility of non-cloud based variations of SDFSS, by quantifying the relative effects of factors such as building construction quality, equipment performance curves, energy pricing structure, and the applicable climate region on resultant cost and GHG emission savings. Functionality bench tests will be conducted to troubleshoot technical issues and assess system performance, by comparing operational data logged by the thermostat to predicted system behavior.

Improving the economic viability of dual-fuel HVAC systems will reduce fossil fuel dependency within the residential heating sector, easing the transition towards low-carbon alternatives without compromising human health, or system reliability. Compatible with current HVAC equipment and smart technology, the proposed solution can improve existing systems while anticipating future innovations in renewable energy, and heat pump technology.